i TAXONOMIC KEYS TO PLANT, SOIL AND AQUATIC NEMATODES BRUCE E. HOPPER and ELDON J. CAIRNS ALABAMA POLYTECHNIC INSTITUTE AUBURN, ALA. 1959 Sponsored By The SOUTHERN REGIONAL NEMATODE PROJECT (S-19) ^ QL . 391. N| A 522 i TAXONOMIC KEYS TO PLANT, SOIL AND AQUATIC NEMATODES BRUCE E. HOPPER and ELDON J. CAIRNS ALABAMA POLYTECHNIC INSTITUTE AUBURN, ALA. 1959 Sponsored By The SOUTHERN REGIONAL NEMATODE PROJECT (S-19) N / . A. PREFACE A few consolidated sources of descriptions and illustrations of plant and soil forms, in particular, are available and should be used along with the taxonomic keys. At best, keys are only attempted short cuts to" the recognition of certain specimens. In all cases check the deci- sions by referral to descriptions and illustrations of the nematodes. There are some excellent volumes available to workers who do not have access to the necessarily large reprint files of the taxonomist. The book by Filipjev & Stekhoven, 19i+l can still be purchased. The book by T. Goodey, 195l is out of print, but can be found in some libraries; so useful a book should be reprinted soon. Fortunately, two other works that every nematologist should have are again available. These are the monographs by Thorne and Swanger, 1936 (reprinted 1957) and Thorne, 1939 (reprinted 19^7 )« V/e have drawn heavily from all of these sources and want to point out that keys are by no means a substitute for the infor- mation contained in these soiorces. The book. Introduction to Nematology by Chitwood & Chitwood, is probably bhe recognized standard work on morphology and will be of great help in anderstanding the morphological terms used in the keys. Volume III of the Invertebrate series by Hyman, 1951 may also be helpful in this re- spect, but to a lesser extent. In utilizing the various sources of information available, a pattern for the reference headings v/as used. Thus, if a new key was developed by the authors, no reference to another source is given. If another author's key was used directly with only minor changes, it is acknowl- edged as being "from" that source. If key contains basically the same information as another source, but with changes having been made in con- tent, it is referred to as being "modified" from the original. If only the form of a key is alteredj^ it is referred to as being "after" the original source. In some cases material from other sources was used as a part of a new key and this is acknowledged by the word "including" in the reference heading. The form in which this syllabus is printed and assembled will enable each owner to keep the information current with the steady outpouring of taxo- nomic work. As revisions of particular groups become necessary, new pages can be typed and inserted along with or instead of the old pages. Addi- tional pages can be conveniently designated with alphabetical characters, for example, 17a. This system will keep the page references intact, A further suggestion to the user 3 insert labeled, tabbed diArLder sheets for qiiicker finding of particular groups. The plan was to provide through this set of keys a foundation on which each person could continue to build and thus maintain a useful working tool. ACKNOVJLEIIGEMKNTS It is a pleasant privilege to be able to call your attention to the source of help in the making of this syllabus. The cost of printing and the initial typing costs were paid from a Rockefeller Foundation Grant awarded to the activities of S-19 Regional Hematology Project for making information more available to new workers and to students, particularly, in phytonematology. The work time allow- ed to the authors and Mrs. Glenda Barnes, who did much of the final man- uscript typing, by Dr. J. A. Lyle, Head of the Department of Botany and Plant Pathology of this Institute, certainly deserves special mention. Wiat had begun as a spare time effort took much more time than just that before it was finished. The loaning and contribution of printed materials from vai'ious sources was of great help in completing and updating cei'tain groups and the gen- erosity of a number of people should be pointed out. Hence, our acknow- ledged gratitude tos E. Altherr, I. Andrassy, E. G. Dougherty; E. Gadea; S. A. Gerlach, H, A. Kreis, M. Luc, A. H. Meyl, F, Paesler, the late J. H. Schuiirmans - Stekhoven, W. Stefanski, A. L. Taylor, and W. Wieser. Special appreciation is due to a nvimber of workers for their wiULngness to discuss the systematic positions of various taxa and the groups at all levels. For this and other help it seems like a small token, indeed, but to list their names: A. D. Baker, B. G. Ghitwood, E. C. Dougherty, J. B. Goodey, A. H. Meyl, A. C. Tarjan, G. Thome, and W. Wieser. Finally, and especially, we want to point out that the great convenience and utility of the taxonomic syllabus prepared by M. W. Allen in 1950 im- pressed upon us through the years we have used it the value of producing another such compilation of keys extended and brought up as much as poss- ible to the present time, Bruce E. Hopper and Eldon J. Cairns Alabama Polytechrdc Institute Auburn, Alabama TABLK OF C0MT1\MTS Preface Acknowledgements Table of Contents Secernentea 1 Spinjrida 2 - Rhabditida 3 Rhabditina h Rhabditoidea 5 Rnabditidae 6 Ghambersiellidae R Cylindroccrporidae 8 Ceohalcbidae lU Diplor^asteridae ?? rylenchida )! Tylenchoidea 2-/ Criconematidae Criconematinae Parat.v lenchinae 28 Dolichodorinae 2f: Hoplolainiidar: 3( Heteroderinae 37 Nacobbinae -"'1 Pratylenchinae 1/ Hoplolainiinae III Tylenchulidae 9 Tylenchulinae c;i Sphaeronematinae 9:- Tyienchidae t'f Paurodontinae z\ Nothotylenchinae k] Neotylenchinae 1 r. Tylenchinae Aphelenchoidea [-[■ Aphelencnoididae 6e Paraphenchj.nae 69 Apheleachinae 69 Parasitaphelenchinae 69 Adenophorea 75 Chromadorida 76 Monhysterina 76 Monhysteroidea 77 Plectoidea 82 Axonolainioidea 86 Chromadorina 76 Desmoscolecoidea 90 Chromadoroidea 90 Desmodoroidea 97 - Enoplida 101 Enopioidea ICl Tripyloidea 111 Trioylidae 111 Alaimidae 112 Mononcbidae 115 Ironidae 119 __ Dorylaimida 120 Dorylairpina 120 Dorylaimoidea 121 Opailaimidae 121 Dorylaimidae 121 Belondiridae 122 Leptonchidae 158 Diphtherophoridae 162 References 166 Aphelenchoidea Biblio'^raphy 17U ■"Errata and Addenda 176 1. Phyllum NmATODA (Rud., I8O8) Cobb, 1919 (Key to the classes modified from Chitwood, 1950) 1. Phasmids present, amphid openings pore-like, labial in position, subventral esophageal glands never opening at or near anterior end of the esophagus. Hypodermal and caudal glands absent. Caudal alae or bursa and rectal glands commonly present. SECERNENTEA (v. Linstow, 1905) Dougherty, 1958 P.l 2. Phasmids absent, amphid openings spiral, circular, vesiculate, pocket- like, tuboid or rarely pore-like, sublabial (not on lips). Bursa absent except for Anoplostoma and Oncholaimellus ; rectal glands usually absent. Hypodermal and caudal glands usually present ADENOPHORA (v. Linstow, 1905) Chitwood, 1958 P. 75 Class SECERNENTEA (v. Linstow, 1905) Dougherty, 1958 (Key to the orders modified from Chitwood, 1950) 1. Esophagus simple cylindrical, or composed of a narrow muscular anterior part and a wide glandular posterior part. Two or more well developed labial structures; if three or six are present, they are reduced in size SPIRURIDA Chitwood, 1933 P. 2 Esophagus divisible into three regions: corpus, isthmus, and bulbar region. Lips usually 3 or 6 in number. 2. Stoma not armed with a stylet, bulbar position of esoohagus with or without sclerotized valvular apparatus. . . .RHABDITIDA Chitwood, 1933 P»3 Stoma armed with a protrusible spear or stylet, basal portion of esophagus glandular without a sclerotized valvular apparatus. TYLENCHIDA Thome 19li9 P.U 2. Order SPIRUMDA Chitwood, 1933 (Key to the suborders from Chitwood, 1900) 1. Esophageal glands uninucleate (ex, Philonema) ; larvae without cephalic 1 ok, phasinids of larvae large, pocket-like. (Inter- mediate hosts copepods.). CMALLANINA Chitwood, 1933 P.? 2. Esophageal glands multinucleate j larvae commonly with cephalic hook, phasraids pore-like. (Intermediate hosts various, rarely copepods.) SPIRURINA Railliet and Henry, 1915 P. 2 Suborder CAMALLANINA Chitwood, 1933 (Key to superfamilies from Chitwood, 19^0) 1. Internal circle of cephalic papillae minute, external circle partially fusedj stoma usually well developed; oviparous or vivip- arous; larvae with pocket-like phasmids. (Intestinal parasites of fish, amphibia, and reptiles.) CAMALLANOIDEA Travassos, 1920 2. Internal cirlce of cephalic papillae well developed, external circle of 8 well developed papillae; stoma rudimentary; vulva in mid-region; viviparous. (Intermediate host copepods.) DRACUNCULOIDEA Cameron, 19. Suborder SPIRURINA Railliet and Henry, 1915 (Key to the superfamilies Chitwood, 1950) 1, Stoma distinctly developed and/or 2 lateral psuedolabia; vulva near middle or posterior of body . . . SPIRUROIDEA Railliet and Henry, 1915 2, Stoma usually rudimentary or reduced; psuedolabia and jaws absent; vulva near anterior end of bodv. (Tissue parasites of vertebrates ex- cept fish.) FILA.itlODEA (Weinland, 1858) Stiles, 190? Order ItHABDITIDA Chitwood, 1933 (Key to the suborders from Cliitwood, 1950) 1. Lips 3> 2 or 0; corona radiata absent; adults with all gradations from rhabditoid to cylindrical esophagus; female reproductive system usually complex, vagina usually heavily muscled; bursa, if present, with papillae; spicules 2, 1 or ASCARIDIM Skrjabin, 1910 P. 3 2. Lips 6, 3 or 0; corona radiata present or absent; feinale reproductive system usually complex, vagina often heavily muscled; adult with clavate type esophagus; bursa usually containing well-developed muscles forming the true or strongylatid bursa STFONGYLINA Pailliet and Henry, 1913 P. U 3. Lips 6, 3) 2 or 0; corona radiata absent; spear present or absent; female reproductive system relatively simple, vagina usually trans- verse and usually not heavily muscled; esoohagus may or may not be terminated by a valved bulb; bursa, if present, containing papillae rather than "rays"; spicules 2 RHABDITINA. Chit., 1935 P. U Suborder ASCARIDINA Skrjabin, 1915 (Key to the superfamily from Chitvrood, 1950) 1. Stoma usually surrounded by esophageal tissue and collapsed (except) Subulurinae); deirids present; mostly large, stout worms; males with 2 spicules ASCARIDOrDEA Railliet and Henry, 1915 2. Stoma cylindroid or short, not siirroimded by esophageal tissue; deirids absent; mostly small or medium-sized transparent worms; males with 1 or 2 spicules OXYUROIDt^IA Railliet, 1905 ii. Suborder STRONGYLINA Raillet & Henry, 1913 (Key to the superfamilies modified from Chitwood, 1950) 1. Male with well-developed bursa, rays not fusedj corona radiata present or absent; stoma well-developed, reduced, rudimentary or absent . . 2 Male with bursa often reduced, rays somewhat fusedj corona radiata absent J stoma reduced, rudimentary or absent ....,...,..,.. MRTASTRONGYLOIDSA Lane, 1917 e • e e o 2, Corona radiata often present, lips absent; stoma usually well- developed, subglobular. . . .STRONGYLOIDEA (Weinland, 1858) Hall, 1913 Corona radiata absent, 6 or 3 inconspicuous lips, or lips absent; stoma reduced; rudimentary or absent; cuticle usually inflated in cephalic region ...,,.,..,.. TRICHOSTRONGYLOIDEA Cram, 192? Suborder RHABDITINA Chitwood, 1935 (Key to the superfamilies from Chitwood, l950) 1. Stoma commonly distinct, lips usually distinct; phasmids pore-like . .,,.,., RHABDITOIDEA Travassos, 1920 P. 5 Stoma greatly reduced, lips rudimentary or absent; phasmids large, pocket-like. (Parasites in the body cavity of earthworms) DRILONMATOIDEA Chit., 1950 oooo«oo*e««ee9 Order TYLENCHIDA Thome, 19U9 (Key to the superfamilies from Chitwood, 1950) 1. Dorsal esophageal gland orifice in precoipus TYLENCHOIDEA (Oerley, 1880) Chit. & Chit., 1937 P. 27 Dorsal esophageal gland orifice in metacorpus , , APHELENCHOIDEA (Puchs, 1937) Thome, 19U9 P. 68 5. Superfamily RHAPDITOIDEA Travassos, 1920 (Key to the families) 1. Esopliagus tenriinated by a valvulated bulb 2 Esophagus not terminated by a valvulated bulb 9 2. Telorhabdions * absent or rudimentary 3 Telorhabdions present it 3. Stoma conoid, protorhabdions fused; male x^ith caudal alae (parasites of molluscs and amphibians) ANGIOSTCMATIDAE Blanchard, I896 Stoma collapsed, protorhabdions feebly sclerotized; male without caudal alae (parasites of arthropods) STEINERI^JEMATIDAE Chit. & Chit., 1937 U. Telorhabdions in the form of a glottoid apparatus 5 Telorhabdions not in the form of a glottoid apparatus 6 5. Monogenetic; 2 or 1 ovary (free-living and parasitic) . RHABDITIDAE Oerley, 1380 ^.^ Heterogenetic; 2 ovaries (parasitic generation in amphidians and reptiles) RHABDIASIDAE Railliet, 1915 6. Corpus elongate, metacorpus usually indistinct, sometimes faintly fusiform 7 Corpus short and thick or metacorpus bulbar 8 7. Lip region with sojc cephalic cirri, cheilorhabdions in fonii of buccal hooks ("odontia" of Cobb), (free-living) CHA1'!BERSIELLIDAE Sanwal, 1957 P«8 Lip region w/o si:?; cephalic cirri, cheilorhabdions not in form of buccal hooks (free-living) CEPHALOHIDAE Chit. 4 Chit., 193h P.lU 8. Two lateral lips present (parasitic in gut of vertebrates) STRONGYLOIDIDAE Chit. & Mcintosh, I93U One lateral lip present (free-living or parasites of invertebrates) DIPLOGASTERIDAE Steiner, 1929 P. 25 9. Telorhabdions plate-like, stoma cylindrical 10 Telorhabdions not plate-like 11 10. Esophagus made up of a procorpus and metacorous blending into a cylindrical muscular esophagus (free-living) CYLINDROCORPORIDAE Goodey, 1939 P. 3 Esophagus without anterior swelling respresenting the corpus (parasite of a sluc^) (Contains a single genus and species, Agfa flexilis (Dujardija 1814;) Chit^ 1935 AGFIDAE Dougherty, 1955 11, Metacorpus indistinct, corpus elongated (free-living or consorts of plants and land-dwelling invertebrates) CEPHALOBIDAE Chit. & Chit., 193U P.lU Metacorous bulbar, or corpus short and thick (free-living or parasites of invertebrates) DIPLOGASTERIDAE Steiner, 1929 P. 25 ■i:- For full discussion of terrninoio;:;y, see Dou'7:ii.ei''t,y, 1.9j5. 6. Family RHABDITUJAE Oerley, I88O (Key to subfamilies after Dougherty, 1955) 1. Dorsal and ventral lips reolaced by paired hook-like structures DIPL0SCAPT(5RINAE Micoletzky, 1922 P. 6 (Contains a single genus, Diploscapter Cobb, 1913) Dorsal and ventral lips not replaced by paired hook-like structures. 2 2. Cuticle highly ornamented; head retractile and with large bristles and lamellae BUNONI^^ATINAE Micoletzky, 1922 P. 7 Cuticle not highly ornamented 3 3. Stom.a terminated by a glottoid apparatus. RHABDITINAE Micoletzky, 1922 P. 8 Stoma not terminated by a glottoid apparatus U U. Stoma cylindrical; broad and foreshortened POIKILOLABINAE Dougherty, 1955 Stoma cylindrical; narrow PROTORHABDITINAE Dougherty, 1955 Incertia sedis: Macramphis Altherr, 1950 Genus Diploscapter Cobb, 1913 D. coronata (Cobb, 1893) Cobb 1913 D. libycus Penso, 1938 D. pachys Steiner, I9J42 D. rhizophilus v. cylindricus Rahm, 1928-1929 Subfamily POIKILOLAIMINAE Dougherty, 1955 Genera: Brevibucca Goodey, 1935 Poikilolaimus Fuchs, 1930 .Subfamily RUNOtJi^iATIi^A f-'! (fiTCOi,l':T^'KY, 19^^) S^irhs, 1V)|9 (f^enei'a and snb^nnera) Pt'^-r,v?orbahditis Timm, 1957 _P. Dakistanensis Timm, 1957 Bunonema Jagerskiold, 1905 1. Bunonema (Jagerskiold, 1905) Sachs, 19U9 B. ditlevseni Micoletzky, 1925 B. hessi Steiner, 191U B. multipapilla"-u m Stefanski, 191U B. penardi Stefanski, 191U B. reticulatvmi Richters, 1905 B. richt^rsi Jagerskiold, 1905 B. steineri Stefanski, 192U B. tuerkonmi Sachs, 19U5 T. Goodey, 1951 also list: B. dactyliciJin Cobb, 1915 B. impar Cobb, 1915 B. inequale Cobb, 1915 B. reticulatum Richters, 1905 B. richtersi v. aberrans Steiner, 19lU B, richtersi v. cantareirense Rahra, 1928 B. steineri Stefanski, 192II Aspidonema Sachs, 19U9 A. niehmi Sachs, 19U9 A. scheuchere Sachs, 19h9 A. stammeri Sachs, 19U9 A. weingaertnerae Sachs, 19U9 3. Craspedonema Richters, 1908 C. javanicimi Richters, 1908 C. styriacum Micoletzky, 1921 C. zealandicum de Man, 1926 T. Goodey, 1951 also lists: C. elegans Rahm, 1928 C. elegans v. paulistanum Rahm, 1928 h. Rhodolaimus Puchs, 1930 R. pini Fuchs, 1930 R. poligraphi Fuchs, 1930 R. ptergiosoma Puchs, 1930 R. pusillus Puchs, 1930 R. stoeckherti Sachs, 19U9 5. Serronema Paesler, 1957 S. dentata Paesler, 1957 6. Stammeria Sachs, 19U9 S. jakobii Sachs, I9U9 S. goffarti Sachs, 19U9 S. helena Sachs, I9I49 8, Subfamily RHAHDITINA'5 (Key to genera modified from Osche, 1952 and following Dougherty, 1955) 1. Male pelodern (bursa not surrounding tail tip) 2 Male leptodem (biirsa surrounding end of tail) 8 2. Spicules fused 3 Spicules not fused 5 3. Vulva posteriorly positioned U Vulva more or less equatoriaily positioned. . Pelodera Schneider, 1966 P. 9 k. Lip region Teratocephalus- like (moveable flap-like lios separated by deep furrows): males rare Teratorhabditis (Osche, 1952) Dougherty, 1953 P-13 Lip region otherwise. . . Mesorhabditis (Osche, 1952) Dougherty, 1953 P.12 5. Vulva posteriorly positioned Pelodera Schneider, 1866 P. 9 Vulva equatoriaily positioned 6 6. Distinct esophageal collar absent Pelodira plicata (Volk, 1950) Dougherty, 1955 Esophageal collar present . 7 7. Glottoid apparatus with two teeth Caenorhabditis (Osche, 1952) Dougherty, 1953 P.12 Glottoid apparatus without teeth Rhabditis Dujardin, l8LiU P. 10 8. Male without preanal papillae; lips Teratocephalus- like Teratorhabditis (Osche, 1952) Dougherty, 1953 P'13 Male with mostly 3 preanal papillae; lips otherwise Rhabditis Dujardin, 18UU P. 10 Other genera: Rhabditonema Korner, 195U Family CHAI-IBRRSIELLIDAE Sanwall, 1957 Genus Chambersiella Cobb, 1920 Single reflexed ovary rodens Cobb, 1920 Two opoosed and reflexed ovaries bakeri Cobb, 1920 Family CYLINDROCORPORIDAE Goodey, 1939 (Key to the genera) Female gonad single, prodelphic Goodeyus Chitwood, 1933 Female gonads paired, opposed and reflexed Cylindrocorpus Goodey, 1939 (Uncertain genus; no specimens or drawings hyctolaimus Cobb, 1920 9. Species Accepted in the RHABDITINAE (From Dougherty-j 1955) 1. Pelodera Schneider, 1866 (19 species). a. Pelodera (Schneider, 1866) Dougherty, 1953 (9 species) I, Pelodera (P. II. Pelodera (P. III. Pelodera (P. IV. Pelodera (P. (type- sp. Hassall, V. Pelodera (P. VI. Pelodera (P. VII. Peloder a (P. VIII. Pe lodera (P. IX. Pelodera (P. ) plicata (Volk, 1950) comb. nov. ) stanimeri (Volk, 1950) comb. nov. ) chitwoodi (Bassen, 19U0) comb, nov. ) strongyloides (Schneider, i860) Schneider, 1866 of genus and subgenus (by selection - Stiles & 1905) ). ) typica (Stefanski, 1922) comb. nov. ) teres Schneider, 1866. ) pimctata (Cobb, 19lU) comb. nov. ) conica (Reiter, 1928) comb. nov. ) litoralis (Skwarra, 1921) comb. nov. b. Cruznema (Artigas, 192?) Dougherty, 1953 (2 species) (syn. Epimenides Gutierrez, 19UU) . I, Pelodera (Cr.) lambdiensis (Maupas, 1919) Dougherty, 1953 (syn, Cruznema cruznema Artigas, 192? - type sp. of sub- genus (by designation) ) . II. Pelodera (Cr.) monhysteroides (Skwarra, 1921) comb. nov. C. Coarctadera Dougherty, 1953 (5 species). I. Pelodera (Co.) coarctata (Leuckart, 1891) Dougherty, 1953 (type sp. of subgenus (by designation) ). II. Pelodera (Co.) cystilarva (Volk, 1950) comb. nov. III. Pelodera (Co.) serrata (Komer in Osche, 1952) comb. nov. IV. Pelodera (C£.) tretzeli (Sachs, 1950) comb. nov. V. Pelodera (Co.) voelki (Sachs, 1950) comb. nov. D. Cylindridera Dougherty, 1953 (3 species) I. Pelodera (Cy.) cylindrica (Cobb, I898) Dougherty, 1953 (type sp. of subgenus (by designation) ). II. Pelodera (Cy.) kolbi (Sachs, 1950) comb. nov. III. Pelodera (Cy.) icosiensis (Maupas, 1916) comb. nov. 10. 2. -Rhabditis Dujardin (18U1|) (6? species) a. Rhabditis (Dujardin(l8i|i|)) Osche, 19^2 (1? species) I. R. (R.) brevispina (Glaus, 1862) Butschli, 1873. fl- R. (R.) terricola Dujardin (1 Qh) (type sp. of genus and subgenus (by selection - Stiles and Hassall/SS?)^ II. fy"- ^' gspera Butschli. 1873). III. R. (R.) maupasi Seurat in Maupas, I919 IV. R. (R. ) verneti Maupas. I90O V. R. (R. ) aberrans Krui^er, I913 VI. R. (R. ) anomala Hertwig, 1922 VII. R. (R. ) caulleryi Maupas. I919 VIII, R. (R. ) guignardi Maupas, I90O IX. R. (R. ) lucianii Maupas, I919 X. R. (R.) terrestris Stephenson, 19i|2 Al. R. (R.) marionis Maupas. I90O XII. R. (R. ) wohlgemuthi Volk, I950 XIII. R. (R.) siivatica Volz, 1951 (syn. Rhabditis silvestris Volz, 1951 ( lapsus for siivatica ) ). • b. Pellioditis Dougherty, 1953 (19 species). I. R. (P.) seurati Maupas, I916 II. R. (P.) papillosa (Schneider, 1866) Orley, I88O. rTr* il ^-^ neopapillosa Mengert in Osche, I952, ^* g^^g^^^i:-) hennaphrodita (Schneider, 1859) comb. nov. ^syn. R. caussaneli Maupas, I90O) V, R. (P.) mairei Maupas. I919 VI. R. (P ) pellio (Schneider, 1866) Butschli, 1873 (type sp of subgenus (by designation) ). ^ ^ ^* °^ VII. a. (p.) pellioides Butschli. 1873 VIII. R. (p.) coffeae Ral-m, I928 IX. R. (P.) butschlii de Man, I876 X. R. (P.) friderici Hirschmann in Osche, 1952 Xi. R. (P.) fluviatilis Butschli, 1876 XII. R. (P.) craspedocerca Volk. I950 XIII. R. (P ) ehrenbaumi Bresslau and Schuumans Stekhoven in Schuurmans Stekhoven, I935 ^ sF;khsifri935"'" "' Schuumans Stekhoven in Sch.unnans XIV. R. XV. R. (P.) voigti Rahm, 1925 XVI. R, (P.) viguieri Maupas, I90O XVII. R. (p.) insolita Paesler, I9ICL XVIII, R. (p.) hartmanni Sachs. 1950 XIX. R. (p.) marina Bastian. 1865 11. C. Choriorhabditis Osche, 1952 (23 species) R. II. R. . III. R. IV. R. V. R. VI. R. VII. R. VIII. R. IX. R. X. XI. R. R. XII. R. XIII. R. XIV. R. XV. R. XVI. R. XVII. R. XVIII. R. XIX. R. XX. R. XXI. R. XXII. R. XXIII. R. Ch.) lonyrj Cauda ta Bastian, 1865 (tj^e sp. of by designation) ) . Ch.) producta (Schneider, 1866) Orley, i860 3ub,^enus Ch. Ch. ^. Ch. Ch. Ch. paraelongata Micoletzky, 1915 duthiersi Maupas, 1900 • brassicae Soughem, 1909 korneri Osche, 1952 macrospiculata Stefanski, 1916 uliginosa Soos, 1938 cristata Hirschmann in Osche, 1952 acarta Ruhm in Osche, 1952 heteruroides Altherr, 1938 dubia Bovien, 1937 heterurus Orley, 1880 gracilicauda de Man, I876 intermedia de Man, I88O filiformis Butschli, 1873 lepida Kreis, 1929j enend, nov. (syn. R. lepidus Ch. Ch. Ch. Ch. Ch. Ch. Ch. Ch. Ch. Ch. Ch. Ch. Ch. Ch. Ch. Kreis, 1929). pseudoelongata Micoletzky, 19lU australis Cobb, 1893 guerneyi Potts, I9IO sechellensis Potts, 1910 lacustris Micoletzky, I9IU sergenti Maupas, I9I6 d. Cephaloboides Rahm, 1928 (6 species) (syn. Cuticularia van der Linde, 1938; Curviditis Dougherty, 1953T'i (Ce.) curvicaudata (Schneider, 1877) Orley, 1885 (Ce. ) oxycerca de Man, 1895 (syn. Cuticularia mathesoni van der Linde, 1938) - type sp. of genus Cuticularia van der Linde, 1938 (by designation) ) . (Ce. ) armata Puchs, 1931 _ (Ce.) ciliata Puchs, 1931 R. (Ce. ) paraciliata Goodey (I9U4) (Ce.) musicola Rahm, 1928 (type of subgenus (by indication monotypy) ; syn. R. pseudoxycerca Goodey, 1929). I. R. II. R. :ii. R. IV. R. V. R. VI. R. e. Rhabditella Cobb, 1929 (2 species). I. E. ( Rhabditella ) octopleura Steiner, 1929, Feb. (syn. R. leptura Cobb, 1929, July - type sp. of subgenus (by designation) ) . II. Rhabditis ( Rhabditella ) axel (Cobbold, I88U) comb. nov. (syn* Leotodera elongata Schneider, 1377, non Baird, 1858; Pelodera axei Cobbold, 188U) 3. KhabdJtoicles Goodey, 1929 (6 soeci'^^'s). a. Kliabditoide s lonfisoina (Kedter, 1928) Doi)p;herty, 195i3 (tyoe so. of penus (by desipination) ) . b. R'-ab di toides incisocaudata (de Coninck, 1935) comb. nov. c; Khabditoides ine r miforr is (Osch^, 1952) coinb. nov. d. hlia bditoides inernds (Schneider, 1866) comb. nov. e. Bhabditoides f^iardi (Maupas, 1^15) comb. nov. f. Rhabditoides henr'aohrodita (Osche, 1952) comb. nov. It. Caonorhabditis (Osche, 19^2) Dougherty, 1953 (10 species) a. Caenorhabditis elegans (Maupas, I9OO) Dougherty, 1953 (type sp. of genus (by designation) ) . b. Caenorhabditis kowalewskyl (Golovin, 1901) comb. nov. c. Caenorhabditis briggsae (Dougherty and Nigon, 19U9) Dougherty, 19^3 d. Caenorhabditis clavopapillata (Kreis and Faust, 1933) comb. nov. e. Caenorhabditis perrieri (Maupas, I9OO) comb. nov. f. Caenorhabditis dolichura (Schneider, I866) comb. nov. g. Caenorhabdit is pseudodolichura (Komer in Osche, 19^2) comb. nov. h, Caenorhabditis carpathica (Soo^s, I9I4I) comb. nov. i. Caenorhabditis debilicauda (Fuchs, 1937) comb. nov. j. Caenorhabditis rara (Komer in Osche, 1952) comb. nov. 5. Mesorhabditis (Osche, 1952) Dougherty, 1958 (18 species) a. Mesorhabditis spiculigera (Steiner, 1936) Dougherty, 1953 (type sp. of genus (by designation) ) . b. Mesorhabditis oschei (Korner in Osche, 1952) comb, nov, c. Mesorhabditis ultima (Komer in Osche, 1952) comb. nov. d. Mesorhabditis tenuispicula (Komer in Osche, 1952) comb. nov. e. Mesorhabditis longespiculosa (Schuurmans Stekhoven, 1951) comb. nov. f. Mesorhabditis juglandicola (Fuchs, 1937) comb. nov. g. Mesorhabditis monhystera (Butschli, 1873) comb. nov. h. Mesorhabditis macrocheila (Kreis, 1932) comb. nov. i. Mesorhabditis cryptocercoides (Wollenweber, 1921) comb. nov. j. Mesorhabditis ocyoodis ( Chitwood, 1935) comb. nov. k. Mesorhabditis quercophila (Ruhm in Osche, 1952) comb. nov. 1. Mesorhabditis graciliformis (Goffart, 1935) comb. nov. (syri. Rhabditis gracilis Goffart, 1935, non Shingareva, Demidova, and Kudrianstev, 1928) m. -Mesorhabditis labiata (Volk, 1950) comb. nov. n. Mesorhabditis belari (Nigon, 19i|9) Dougherty, 1953 o. Mesorhabditis irregularis (Komer in Osche, 1952) comb, nov. p. Mesorhabditis acris (B astian, 1365) comb, nov, q, M esorhabditis inarimensis (Meyl, 1953) comb. nov. r, "incertae sedis;? R'esorhabditis acrjninata (Kreis, 1929) comb, nov. 13. 6. Teratorhabditis (Osche, 1952) Dougherty, 1953 (h species) a. Teratorhabditis dentifera (Volk, 1950) Doup;herty, 19$3 (type sp. of genus (by desiPTiation) ) . b. Teratorhabditis coronie^er (Altherr, 1938) comb. nov. a. Teratorhabditis chitinolabia ta (Schneider, 1938) comb. noy. d. Teratorhabditis boetts;eri (Meyl, 1953) comb. nov. 7. Protorhabditis (Osche, 1952) Dougherty, 1953 (12 species). a. Protorhabditis xylocola (Komer in Osche, 1952) Dougherty, 1953 (type sp. of genus (by designation) ). b. Protorhabditis janeti (de Lacaze-Duthiers in Janet, 1893) comb. nov, c. Protorhabditis oxyuris ( Glaus, 1862) comb. nov. d. Protorhabditis ornata (Bastian, 1865) comb. nov. e. Protorhabditis ant hob i a (Schneider, 1938) comb. nov. f. Protorhabditis elaphri (Hirschmann in Osche, 1952) comb. nov. g. Protorhabditis tristis (Hirschjmann in Osche, 1952) comb. nov. h. Protorhabditis virgo (Komer in Osche, 1952) comb. nov. i. Protorhabditis postneri (Komer in Osche, 1952) comb. nov. j. Protorhabditis parvovelata (Komer in Osche, 1952) comb. nov. k, Protorhabditis ruhmi (Komer in Osche, 1952) comb. nov. 1. Protorhabditis minuta (Cobb, 1893) comb, nov. 8. Parasitorhabditis (Puchs, 1937) Chitwood, 1950 (2 species) a, Parasitorhabditis obtusa (Fuchs, 1915) Dougherty, 1953 (type sp. of genus (by indication - monotypy) ). b. Parasitorhabditis ateri (Fuchs, 1937) Skriabin. et al., 19 5U 9. Incertae sedis ; Brevibucca Goodey, 1935 (2 species) a. Brevibucca saprophaga Goodey, 1935 (type sp. of genus (by designation) J. b, Brevibucca frugicola Goodey (19U3) lU. Family CEPHALOBIDAE Chit. & Chit., 193U (Key to the subfamilies adapted from Thome, 1937) 1. Female with two ovaries . . . .ALLOIONMATINAE Chit. & Mcintosh, 193U Female with one ovary 2 2. Stoma much reduced, only cheilorhabdions developed. Basal esophageal bulb without valvular apparatus . . . .DAUBAYLINA7. Chit. & Chit., 193U Sterna not reduced. Basal esophageal bulb with valves 3 3. Pharyngeal armature cephaloboid. Double flexure in ovary posterior to vulva (except in occasional aberrant specimens). Spermatheca present at anterior flexure of ovary. Annules about 2u or more wide.U Pharyngeal armature panagrolaimoid. Ovary never with double flexure posterior to vulva. No spermatheca present at anterior flexure of ovary. Annules fine, much less than 2u wide. PANAGROLAmiNAR Thome, 1937 P.l6 k^ Lip region bearing 3 labial, and frequently 6 cephalic probolae ACROBELINAE Thome, 1937 P. 19 Lip region without probolae CEPHALOBINAE Filipjev, 193U P.lU Subfamily CEPHALOBINAE Filipjev, 193U (Key to genera after Thome, 1937) Wings extending to caudal terminus, female tails blunt and rounded Cephalobus Bastian, 186^ P.lU Wings extending only to phasmids, female tails attenuated Eucephalobus Steiner, 1936 P. 15 Genus Cephalobus Bastian, 186^ C. brevicaudatus Zimmermann, I898 C. buchneri Meyl, 1953 C. cornis (Thome, 1925) Thome, 1937 C. dubras Maupas, 1900 C. nannus de Man, I88O C. parvus Thorne, 1937 C. persegnis Bastian, 1865 C. strandi-comutus Allgen, 193U C. thermophilus Meyl, 1953 15. Genus Bucephalobus Steiner, 193'^ (Key to species from Allen, 1950) 1. Lips distinct, pointed, not amalgamated 2 Lips completely amalgamated, low rounded 3 2. Terminus of female tail bluntly rounded, male tail mucronate striatus (Bastian, 1865) Thorne, 1937 Terminus of female tail not bluntly rounded, male tail without mucronate process oxyuroides (de Man, 1876) Steiner, 1936 3. Lips separated by deep axils laevis Thorne, 1937 Lip not separated by deep axils U U. Nerve ring surrounding base of corpus .latus (Cobb, 1906) Thome, 1937 Nerve ring encircling corpus about one neck width anterior to jixnction with isthmus teres Thorne, 1937 Other species: E. bipapillatus (Stefanski, 191^) Thome, 1937 E. bisimilis (Thome, 1925) Thome, 1937 E. compus (Steiner, 1935) Thorne, 1937 E. diversipapillatus Altherr, 1950 E. elongatus (de Man, 1880) Thome, 1937 E. multicinctus (Cobb, 1893) Thorne, 1937 E. mylakolaimus (Puchs, 1930) Thorne, 1937 E. nannus Steiner, 1936 E, paracomutus de Coninck, 19U3 16. Subfamily PANAGROL.A?"TNA'^ (Key to the c^enera) 1. Lip region bearing 6 inward-pointing, flap-like process vrith strongly sclerotized borders Pana' robe Ins Thorne, 1939 P. 17 Lip region otherwise ( 2 species, both maybe beetle assc .iates) . . 2 2. Circlet of 6 setose cephallic papillae present ......... o MacrolaJP'-us Maupas, 1900 P.l? Cephalic papillae not setose 3 3. Post corpus of esophagus bulbar, separated by distinct break in the corporeal lining. . . , Tricenhalobus Steiner, 1936 P. 17 Post corT)us of esophagus not bulbar h h. Plate-like denticles present in pharynx 5 Plate-like denticles absent in pharynx 6 5. Isthmus about as long as corous Pana ~rodontu s Thome, 1935 (U species, all maybe bark-boring beetle associates) Isthjnus much shorter than corpus Turbatrix Peters, 1927 (T. aceti Muller, 1783) aceti Peters, 1927 is the vinegar eel- worm and T. aceti (Muller, 1783) dryoohila (Leuckart, 1887) de Kan, 1910 has been as an inhabitant of white slime-flux of oak.) 6. Ovary lying entirely anterior to vulva. . . . . Plectonchus Puchs, 1930 (3 species bark beetle associates) Ovary extending caudad past vulva 7 7. Cheilostom hexagonal, the rhabdions consoicuous • • • Procephalobus Steiner, 193U (Contains a single species P. mycophilus Steiner) Cheilostom triquetrous, the rhabdions obscure 8 8. Tips of spicula bifid ...... Pana-rellus Thorne, I938 P. 18 Tips of spicula not bifid 5) 9. Male vrith ventromedian, preanal papillae. . Neocephalobus Steiner, I939 P.17 Male without ventromedian, preanal papillae .Panagrolaimus Fuchs, I93O P. 18 17. Genus Panayrobelus Thome, 1939 (Key to the species) Female 1.0 mm and male 0.9 nun in length; tt-ro pairs of preanal and two pairs of postanal ventrosubmedian male papillae incisus Thome, 1939 Male and female length 0.5 fnm; three pairs of preanal and three pairs of postanal ventrosubmedian male papillae coronatus (Fuchs, 1930) Thome, 1939 Genus Macrolaimus Maupas, 1900 (Key to the species Allen, 1950) Male and female tails with terminal hook, lips forming high arch over vestibule hamatus Thome, 1937 Tails without terminal hook, arch over vestibule slight taurus Thome, 1937 Other species: M. aculeatus (Daday, 190^) Thome, 1937 M. crucis Maupas, 1900 M. papillatus (Rahm, 1928) Goodey, 1951 Genus Tricephalobus Steiner Contains : T. acuminatus (Kreis, 1929) Goodey, 1951 T. labiatus CKreis, 1929) Goodey, 1951 T. longicaudatus Steiner, 1936 Genus Fleet on chus Fuchs, 1930 Contains : P. atari Fuchs, 1930 P. cuniculari Fuchs, 1930 P. ligniperdae Fuchs, 1930 All three species occurred in the frass of bark beetles in Europe, Genus Neocephalobus (Steiner, 1929) Steiner, 193U [Key to species) Three lips, each consisting of 2 more or less distinctly amalga- mated lips; in male ventromedian papilla adanal peruensis Steiner, 1939 Six uniform lips; in male ventromedian papilla in latitude of proximal end of spicula . . . . ' aberrans (Steiner, 1929) Steiner, 193U 1«. Genus Panagrellus Thome, 1938 (Key to the species) Males 1. Spicules without bifid tips . . . ludwi-^jj (de Man, 1910) Goodey, 19U5 Spicules with bifid tips 2 2. Spicules without ventral membrane expansion extending from head to tip leucocephalus (Steiner, 1936) Goodey, 1914? Spicules with ventral membrane expansion extending from head to tip .3 3. Spicule head without forward directed hook k Spicule head with forward directed hook 5 h. Distal end of gubemaculum folded over to form a kind of loop reclivivoides (Goodey, 19U3) Goodey, 19h5 Distal end of gubemaculum not formed into a loop nepenthicola (Menzel, 1920) Goodey, I9I4.5 5. Spicule length about U 2 times length of guoemaculum pycnus Thome, 1938 Spicule length less than 3 times length of gubemaculum 6 6. Hook on head of spicule swollen and knob-like redivivus (Linn., 176?) Goodey, 19i;5 Hook on head of spicule fairly uniform in width, not knobbed silusiae (de Man, 1913) Goodey, 19^5 Genus Panagrolaimus Puchs, 1930 Contains : P. annulatus (Skwarra, 1921) Thome, 1937 P. chalographi Puchs, 1930 P. detritophagus Puchs, 1930 P. haloohilus Meyl, 195U P. heterocheilus Steiner, 1935 P. hygrophilus Bassen, I9U0 V. obesus Thome, 1937 P. paralongicaudatus (Altherr, I938) Goodey, 1951 P. picei Puchs, 1930 P. piniperdae Puchs, 1930 P. rigidus (gchn., 1866) Thome, 1937 P. sexadentata Puchs, 1930 P. spondyli Komer, 195U P. subelongatus (Cobb, I9II;) Thorne, 1937 P. siiporbus Fuchs, I93O F. thienemanni Hirschmann, 1952 P. venustus Fuchs, I93O 19. Subfamily ACROEHIINAE Thome, 1937 (Key to genera after Thorne, 1937) 1. Labial probolae massive, low, rovinded or furcate plates 2 Labial probolae slender, furcate or elaborately fringed 5 2. Cephalic axils dentate, female tails concave- conoid to acute or sub- acute terminus Zeldia Thorne, 1937 P. 19 Cephalic axils not dentate (except minutely in Chiloplacus trifurcatus ), fanale tails bluntly-rounded, rarely convex- conoid. . 3 3. Labial probolae, at least the dorsal one, furcate, the submedian ones usually asymmetrical Chiloplacus Thome, 1937 P. 20 Labial probolae low, rounded, not furcate U U. Esophagus well developed with enlarged postcorpus, cuticle near head with simple annules Acrobeloides Cobb, 192U P. 21 Esophagus slender throughout, cuticle near head divided into plates Placodira Thome, 1937 (Contains a single species P. lobata Thome, 1937) 5. Labial probolae elaborately fringed . . . .Acrobeles von Linstow, 1877 P. 22 Labial probolae slender, furcate, rarely with a few branches v ... 6 6. Cuticle with transverse striae only Cervidellus Thorne, 1937 P. 23 Cuticle with both longitudinal and transverse striae Stegelleta Thome, 1938 P. 23 Genus Zeldia Thorne, 1937 (Key to the species after Allen, 195o) 1. Labial probolae low and rovmded punctulata (Thome, 1925) Thome, 1937 Labial probolae plate-like, bifurcate 2 2. Annules marked by h lines of punctate dots punctata (Thome, 1925) Thorne, 1937 Annules not marked by pimctate dots 3 3. Excretory pore far in front of nerve ring glaphyra (Steiner, 1935) Thorne, 1937 Excretory pore located near the nerve ring setosa (Cobb, 191U) Thome, 1937 (Description derived from an immature specimen) 2n. Genus Chiloolacxui 'I'horne, 1937 (Key to species froii' Allen, 19^0) 1. Cephalic probolae low, rounded at axils 2 Cephalic probolae pointed at axils 5 2. Labial probolae bifurcate, branches bifurcate 3 Labial probolae bifurcate, branches not bifurcate Ii 3. Branches of labial probolae obscurely bifurcate demani (Thome, 1925) Thome, 1937 Branches of labial probolae distinctly bifurcate, inner branches almost meeting incurvis (Thome, 1925) Thorne, 1937 1|. Submedian labial probolae asymmetrical propinquus (de Plan, 1921) Thorne, l:^'3j Labial probolae symmetrical (genotype) s}TTimetricu3 (Thorne, 192b>) Thorne, 1937 5. Labial probolae low, truncate, not bifurcate truncatus (Thorne, 1925) Thome, 1937 Labial probolae bifurcate 6 6. Labial probolae bifurcate, branches bifurcate trifurcatus (Thome, 1925) Thome, 1937 Labial probolae bifurcate, branches not bifurcate 7 7. Wing area with i; lines. . . quardricarinatus (Thome, 1925) Thome, 1937 Wing area with 2 or 3 lines 8 3. Submedian labial probolae asymmetrical. . . . trilineatus Steiner, 19U0 Submedian labial probolae symmetrical 9 9. Labial probolae bifurcate 1/3 their length bisexualis (Micol., 1916) Thome, 1937 Labial probolae bifurcate 1/2 their length. . . 10 10. Labial probolae short, 2 lines in lateral fields denticulatus (Thome, 1925) Thorne, 1937 Labial probolae moderately long, 3 lines in lateral fields lentus (Maupas, 1900) Thome, 1937 Others: C. obtusicaudatus (Kreis, 1930) Thome, 1937 21. Genus Acrobeloides (Cobb, 192h) Thome, 1937 (Key to species from Thome, 1937) 1. Labial probolae low and rounded , 2 Labial probolae not low and rounded 7 2. Cephalic probolae setose. . . bodenheimeri (Steiner, 1936) Thome, 1937 Cephalic probolae not setose. ... 3 3. Tails of females clavate. . . clavicaudatus (Thome, 1925) Thome, 1937 Tails not clavate k U. Labial probolae asymmetrical. . cubaensis (Steiner, 1935) Thome, 1937 Labial probolae not asymmetrical 5 5. Female tails pointed apiculatus (Thome, 1925) Thome, 1937 Female tails blunt, rovinded 6 6. Length about 1.0 mm maxmus (Thome, 1925) Thome, 1937 Length about 0.5 mm . minor (Thome, 1925) Thornej^ 1937f 7. Labial probolae connate ^ Labial probolae with setose or cylindrical points-. » 8. Tail bluntly rounded (^eaotype) . .. .. butschlii (de Man, 188U)) Stjeiner it Buhrer, 1933 Tail obliquely truncate obliquus (Thome, 1925) Thome, 1937 9. Labial probolae conoid then cylindrical to lip „ tricomis (Thome, 1925) Thome, 1937 Labial probolae low, rounded with setose points, enoplus Steiner, 1938 Others; A. emargig^tus (de Man, 1880) Thome, 1937 and A. variabilis (Steiner, 193^) Goodey, 1951. 22, Genus Acrobeles von Linstow, 1877 (Key to species from Allen, 1950) lo Labial probolae bifurcate, branches without tenminal bifurcation cephalatus (Cobb, 1901) Thome, 1925 Labial probolae bifurcate, branches with terminal bifurcation „ . , 2 2. Cephalic probolae long and slender 3 Cephalic probolae short and triangular. ....... U 3. Membranes on cephalic probolae extending about 1/2 the distance to the apex serricomis Thome, 1925 Membranes on cephalic probolae extending to apex (genotype) ciliatus von Linstow, 1877 U. Terminal branches of labial probolae recurved o . . . 5 Terminal branches of labial probolae not recurved 6 5. Membranes on labial probolae bluntly rounded, phasmid near middle of tail ornatus Thome, 1925 Membranes on labial probolae triangular acute, phasmid near level of anal opening elaboratus Thome, 1925 6. Phasmids almost opposite anus . ctenocephalus Thome, 1925 Phasmids near middle of tail complexus Thome, 1925 Others: A. complexus Thome, 1925; A. sinensia Kreis, 1930; A. soosi Andrassy, 1953. 23. Genus Cervidellus Thome, 1937 (Key to the species from Allen, 1950) 1. Cephalic prcbolae serrate, edges sclerotized 2 Cephalic probolae not serrate, but flap-like U 2. Labial probolae bifurcate l/U their length serricephalus (Thojme, 192^) Thome, 1937 Labial probolae bifurcate 1/2 their length 3 3. Branches of labial probolae slender, not rebranched serratus (Thome, 192^) Thome, 1937 Branches of labial probolae rebranched, 1 forward and 2 backward pointing branches . . . .(genotype) cervus (Thome, 1925) Thome, 1937 U. Labial probolae doubly furcate, terminal branches recurved hamatus Thome, 1937 Labial probolae bifurcate only 5 5. Labial probolae bifurcate 3/U their length, branches recurved ankyrus (Thome, 1925) Thorne, 1937 Labial probolae bifurcate less than 1/2 their length 6 6. Cephalic axils with sclerotized points at base similis (Thorne, 1925) Thome, 1937 Cephalic axils without sclerotized points 7 7. Cephalic probolae ending in bristle-like points 8 Cephalic probolae flap-like, bifurcate insubricus (Steiner, 19lU) Thome, 1937 8. Gubemaculum triangular in shape kruguelensis (Steiner, 1916) Thome, 1937 Gubemaculum slender, not triangular vexilliger (de Man, 1880) Thome, 1937 Genus Stegelleta Thome, 1938 (Key to the species from Allen, 1950) 1. Cephalic probolae low and rounded . incisa (Thome, 1937) Thorne, 1938 Cephalic probolae flap-like, pointed 2 2. Labial probolae bifurcate 1/2 their length, outer branches recurved cancellata (Thorne, 1925) Thorne, 1938 Labial probolae bristle-like, bifurcate l/U their length, branches not recurved lineata (Thorne, 1925) Thorne, 1938 2$. Family DIFLOGASTERIDATC Steiner, 1929 (Key to subfamilies modified from Chitwood, 1950) 1. Stoma consisting of 2 well developed parts in tandem; teeth, if present, in posterior part of stoma CEPHALOBIINAE Filipj., 193U P. 26 Stoma otherwise 2 2. Stoma narrow, with basal enlargements simulating a stylet TYLOPHARYNGINAE Filipj., 1939 (Contains a single species, Tylopharynx striata (de Man, 1876) Goodey, 1951) Stoma not simulating a stylet 3 3. Stoma very short and wide, retrose teeth at base present or absent PRISTIONCHINAE Chit., 19$0 P. 26 Stoma not short and wide h U. Prostom wide, heavily sclerotized, containing large retrose teeth, metastoma collapsed or very weakly sclerotized; labial rugae prom- inent DIPLOGASTERINAE Micol., 1922 P-26 Stoma cylindrical to prismatoidal or collapsed; labial rugae absent or very weak DIPLOGASTRROIDINAE Filipj. & Stek., 19hl ^'^^ Subfamily DIPLOGASTcHOrDINAE Filipj. & Stekh., 19Ul (Key to the genera modified from Allen, 1950) 1. Pharynx without teeth, denticles or glottoid apparatus Rhabditolaimus Fuchs, 1915 Pharynx armed with a dorsal tooth 2 2. Armature in anterior end of pharynx .... Neodlplogaster Cobb, 192U Armature in basal portion of pharynx 3 3. Median biilb elongate, not distinctly set off from corpus of esophagus Demaniella Steiner, I9IU Median bulb rounded, distinctly set off from corpus of esophagus h 1;. Male tail without a bursa 5 Male tail with an obscure postanal bursa Rhabdontolaimus Flichs, 1931 5. Stoma cylindrical Diplogasteroides de Han, 1912 Stoma barrel-shaped Goffartia Hirschmann, 1952 2A. Subfamily CEPHALOBIINAE FilipjeVj 193U (Key to the genera) 1. Head bearing six setae, .... = ..,„ ^ . « Butlerivis Goodey, 1929 Head without setae 2 2. Stoma with massive tooth in basal part, opposing denticles present or absent o 3 Stoma without massive tooth but with large dorsal tooth-like "glot- toid organ" Cephalobiim Cobb, 1920 3. Tooth opposed by denticles Odontopharynx de Man, 1912 Tooth not opposed by denticles Acrostichus Rahm, 1928 Others: (?) Loxolaimus Rahm, 1928 Subfamily PRISTONCHINAE Chitwood, 1950 (Key to the genera modified from Allen, 1950) 1. Stoma broad, shallow and unarmed Lycolaimus Rahm, 1928 Stoma broad, armed at base 2 2. Esophagus with a constriction behind the median bulb Paradiplogaster Stekhoven & Teunissen, 1938 Esophagus without constriction, stoma amed at base with 3 curved teeth Pristionchus Kreis, 1932 Others: (?) Peronilaijtius f?ahra, 1928 which contains a single species P. saccai Rahm, 1928. Subfamily DIPLOGASTEF;lNAE Micoletzky, 1922 (Key to the genera modified from Allen, 1950) Tooth well fonvard in stoma, thumb-like, a large fixed denticle a- rising from the pharyngeal wall at right of tooth Mononchoides ftahan, 1928 Dorsal tooth near base of pharynx, may be opposed by tooth on ventral side Diplogaster Schulze, 1857 27o Superfaraily TYLENCHOIDRA (Oerley, I88O) Chit. & Chit., 1937 (Key to the families) 1. Esophagus distinct 5 esophageal musculature present. = . « „ » . » . 2 Esophagus degenerate I esophageal musculature absent (animal para- 2. Cuticle usually heavily annulated or squamous, often bearing spines; spear greatly elongated. CFICGNmATIDAE Thome, 19l;3 (defined Thome, 19U9) P.2& Cuticle finely to moderately annulated, plain; spear short. .... 3 3. Head with internal cephalic sclerotization HOPLOLAmiDAE (Filipj., I9UI) Wieser 1953 P. 37 Head without internal cephalic sclerotization U U. Female swollen to saccate TYLEI-JCHULIDAE Raski, 1957 P.5U Female vermiform TYLENCHIDAE Oerley, 1830 ?.^^ 5. Sucker-like vesicle at excretory pore .... MYENCHIDAE Pereira, 1932 Terminal excretory duct tubular . ALLANTONTiMATIDAE Chit. & Chit., 1937 syn. (?) CONTORT YLENCHIDAE (Ruhm, 19^6) Chitwood, 1958 28. Family CRICONmATIDAE Thome, 19Jb3 (defined Thorne, 19h9) (Key to the subfamilies modified from Chitwood, 1950) 1. Cuticular striations interupted by 8 or nore lateral incisures » » . 2 Cuticular striations not interupted laterally by incisures CRIC0NH4ATIME Taylor, 1936 i\?C 2. Cuticle finely annulated; females minute, elongate or short and thick PARATYLENCHINAE Thorne, 19U9 P. 23 Cuticle coarsely annulated; both sexes of moderate size, very elon- gate, eel-shaped DOLICHODORINAE Chitwood, 1950 P.2C Subfamily CRICOMH^iATINAE Taylor, 1936 (Key to the genera) 1. Mature female retaining last moltj body annules not retrose .... 2 Mature female not retaining last molt; body anniiles retrose .... 3 2. Knobs of stylet with anteriorly directed processes Hemicriconemoides Chit. & Birchfield, 1957 P. 30 Knobs of stylet with posteriorly sloping processes Hemicycliophora de Man, 1921 P.?9 3. Cuticular spines or scales present in adults Criconema Hoftnanner & Menzel, 19lU P. 31 Cuticular spines or scales not present in adults Criconemoides Taylor, 1936 P. 33 Subfamily PARATYLENCHINAE Thome, 19U9 (Key to the genera) 1. Female body obese, swollen; male with adanal bursa Cacopauius Thome, 19U3 P. 35 Feraale body not swollen or distorted; bursa absent in male Paratylenchus Micoletzky. 1922 P. 36 Other genera: Macropos th onia annulata, female unknown, appears more like males of priconematid genera. Subfamily DOLICHODORINAE Chitwood, 1950 (Key to the genera) Esophageal glands lying free in body cavity, overlapping the intest- ine; male with adanal caudal alae Belonolaimus Steiner, 19U9 P.35 Esophageal glands enclosed in terminal bulb, not overlapping the intestine; male with terminal caudal alae . . .Dolichodorus Cobb, 19lU P«35 1'). Genus Hemicycliophora de Man, 1921 (Key to the species) 1. Annules of lip region distinctly separated. . . . hesperis Raski, 195^3 Annules of lip region not separated « ^ » oo o <> = .....,. , 2 2. Terrainus acute or subacute ^ . . , 3 Terminus blunt, rounded .......... 22 3- Length about O.U mm straeleni de Coninck, 1931 Length 0.7 mm or more li l|. Tail long, attenuated 5 Tail not attenuated 7 $. Neck cylindroid to truncate lip region 6 Neck tapering to rounded lip region gigas Thome, 1955 6. Spear 6l-65u long; body annules 256-263 paradoxa Luc, 1958 Spear 132u longj body annules about UOO micoletzki (Goffart, 19U8) Goffart, 1952 7. Body slender, a- 33-36 8 Body more robust, a= 19-26 9 8. Length 1.0 mm, body arcuate arcuata Thorne, 1955 Length I.I4. mm, body not arcuate tenuis Thorne, 1955 9. Body marked by numerous longitudinal striae 10 Body not marked by longitudinal striae I3 10. Tail concave conoid 11 Tail uniformly conoid 12 11. Lateral fields 1/3 the body width, transversely striated into rectan- gles penetrans Thorne, 1955 Lateral fields 1/5-1/6 the body width, transversely striated into squares oostenbrinki Luc, 1958 12. Lateral fields a single line of rectangles. . . penetrans Thome, 1955 Lateral fields with a double row of squares . . oostenbrinki Luc, 1958 13. Cuticle ornamented with delicate longitudinal markings aquaticum (Micoletzky, 1913) Loos, 19U8 Cuticle not ornamented with longitudinal markings lU lU. Body tapering rather viniformly from vulva to sub-acute terminus . . 15 Body not tapering uniformly, tail concave conoid. . . , 18 15. Vulva-terminus distance three times spear length, parvana Tarjan, 1952 Vulva-terminus distance twice spear length or less 16 30. 16,, Iiip re^rion naiTowod, rounded, . . . . o » . . . iirii L'oirTi .is Thorn'.-, 19^.'> Lip region broad, truncated 17 17o Lateral fields marked by 2 incisur'-^s . <,.<,,», conirlia Tborne, 19!>5^ Lateral fields without incisures, ...,». . paucisnnulnta Luc, 1^50 18. Length near 1.2 nwi, ....o.............. «.»... 19 Length near 1.7 mm . . , . , gracilis Thome, 1955 19. Bisexual species with many males. ........ .typica de Man, 1921 Monosexual species as far as is known 20 20. Body narrowing rapidly behind vulva thienemanni (Schneider, 1922, 1925) Loos, 19il8 21. Spear length 90-lOUu similis Thome, 1955 Spear length 112-122u vidua Raski, 1958 22. Terminus convex or irregular conoid to blunt terminus 23 Temiinus hemispheroid 27 23. Tail uniformly convex conoid ' 2U Tail irregularly conoid to blunt terminus 26 2k. Vulva-terminus distance less than spear length 25 Vulva-terminus distance one and one-half times spear length obesa Thome, 1955 25. Spear length ll6-120u brevis Thome, 1955 Spear length 69-83u epicharis Raski, 1958 26. About 20 annules between vulva and terminus . . .aberrans Thome, 1955 About 55 annules between vulva and terminus . . striatula Thome, 1955 27. Length 1.2 mm rotundicauda Thome, 1955 Length about 0.8 mm 28 28. Body with ventral contraction at vulva 29 Vulva continuous with body contour nana Thome, -1955 29. Spear length 86-lOOu arena ria Raski, 1958 Spear length 120u . obtusa Thorne, 1955 Genus Hemicriconemoides Chit, & Birchfield, 1957 (Key to the species) 1. Tail somewhat subdigitate wessoni Chit. & Birchfield, 1957 Tail blunt, conical, or pointed 2 2. Tail bluntly rounded, brachyurus (Loos, 19U7) Chit. .& Birchfield, 1957 Tail conical and/or pointed . 3 3. Body annules 120 or more; spear length over 70u gaddi (Loos, 19U9) Chit. & Birchfield, 1957 Body annules approximately 100; spear length U8-56u cocophilus (Loos, 19U9) Chit. & Birchfield, 1957 31. Genus Criconema Hofmanner and Menzel I9II4 (Key to specif^s after Chitvrood, 1957) 1. Annules 100 or more 2 Annules less than 100 3 2. Annules about l50; spines short and wide souanosum (Cobb, 1913) Taylor, I936 Annules probably 100-120; spines triangular, in 6 lonp;itudinal roiTrs quemei (Certes, I889) Hoftnanner & Menzel, I9IU 3. Fringe continuous on each annule k Fringe in strips or roijs of distinct spines present (not over 16 per annule) 6 U. Annules numbering U5; 70-80 spines in continuous fringe; stylet 98 microns (vide Sveshnikova 89 microns) multisquamatum (Kirjanova, 19li8) Chitwood, 19^7 Annules 53 or more 5 5. Annules numbering 53; about kO spines per annule in midregion; stylet 96 microns long fimbriatum Cobb 1936 in Taylor, I936 Annules numbering 60-70; about 60 spines in fringe; stylet 96-I3O microns long mengeli (Stefanski, 192U) Taylor, I936 6. Spines in a discontinuous fringe of 32-U8 per annule in 8 longitudinal bands civellae Steiner, I9U9 Spines or scales in few (U-I6) longitudinal rows 7 7. Spines in only k longitudinal rows: 1 dorsal, 1 ventral, 2 lateral; 69-73 annules; stylet Sb-60 microns long minutum (Kirjanova, 19U8) Chitwood, 1957 Spines or scales in 8 or more longitudinal rows 8 8. Spines or scales in 16 longitudinal rows • , 9 Spines in U-12 longitudinal rows 10 9. Spines rather blunt and scale like, not very narrow ev^en in posterior body region; annules 62-6U; stylet 96 microns long cobbi (Micoletzky, 1925) Taylor, 1936 10. With I4-8 rounded scale rows; annules numbering 77; stylet about 52 microns long lentiforme (Stekhoven and Teunissen, 1933) Chitwood, 1957 With 8, 10, 12, or 8-12 longitudinal rows of spines or scales. ... 11 11. Scales in 8-12 or 12 longitudinal rows. 12 Scales or spines in 8-10 longitudinal rows 13 32. 12. Scales in 8-12 rowsj rounded at side dentate or wholly trifid; f>l annules} stylet 82 microns »..„.,»,. tripium (Stekhov3n & Tetinissen, 1935) Chitwood, 19'^7 Scales in 12 longitudinal rows; bluntly triangular with side teeth, often somewhat tridentate; \\2 annules| stylet 9^^$ microns triconodon (Stekhoven & Teunissen, 1938) Chitwood, 19?? 13. Spines in 10 longitudinal rows; annulesj stylet 66-85 microns lon,^ . decalineatum Chitwood, 1957 Spines or scales in only 8 longitudinal rows Ill lU. Spines mostly longer than vxide \$ Spines mostly wider than long or about equal 16 15. Vulva at 15th annule from terminus; annules numberin,?^ 68-71 murrayi (Southern, I9IU) Taylor, 1936 Vulva at 17th - 18th annule from terminus; annules numbering 89; stylet UO microns long spinalineatum Chitwood, 1957 16. Annules 65-75> large broad scale-like; vulva at 12th annule from terminus; stylet 63 microns long octangulare (Cobb, I9IU) Taylor, 1936 Annules 66; vulva at 10th annule from terminus; stylet 92 microns zernovi (Kirjanova, I9U8) Chitwood, 1957 33. Genus Criconemoidea Taylor, 1936 (Key to the species modified from Raski, 1958) 1. Spear length 90 microns or less ...,,=.,,= .c, .... . 5 Spear length 100 microns or more. ...,..,.,.. 2 2. Total body annules 95 or more . 3 Total body annules 58-61. . , . annulifer (de Man, 1921) Taylor, 1936 3. Length .U5 mm. or morej spear not very long and thin (less than 1/3 of Length .27-. 30 mm.j spear very long and thin (more than 1/3 of body length) ,...,,..»...,.,, o . . macrodorum Taylor, 1936 U. Spear 105 micronsj total body annules lUOj length .88-1.00 mm ........................ annulatum Taylor, 1936 Spear 122 micronsj total body annules 95-103; length .U6 mm . . o sphagni (Micoletzky, 1925) Taylor, 1936 «*o«eo«90o 5. Tail rounded. . , ,,.... ^ . 11 6« Total body annules less than 80 ........... 8 Total body annules 110 or more 7 7. Length .70 mm.; vulva on 16-17 annule from, terminus ..... komabaensis (imamura, 1931) Taylor, 1936 Length .55-. 59 mm.; vulva on 8th annule from terminus . . morgense (Hoftianner and Menzel, 19lU) Taylor, 1936 8. Total body annules 70 or more 9 Total body annules 65 ........... . heideri Stefanski, 1916 9. Vulva located on 12-l5th annule from terminus; total body annules 70- 76 10 Vulva located on 7th annule from terminus; total body annules 79 . peruense (Steiner, 1920) Taylor, 1936 10. Length ,70 mm.; first annule larger than second annule ^ crotaloides (Cobb, 192U) Taylor, 1936 Length .U0-U9 mm. ; first annule smaller than second annule , . demani (Micoletzky, 1925) Taylor, 1936 11. No joints on lateral line, annules unbroken except occasional anasto- mosis lU Joints on lateral line except on anterior end of body 12 12. Lateral line zig-zar?;; spear 57 microns or more 13 Lateral line with simple breaks; spear 50 microns . citri Steiner, 19U9 3U. 13. Length .30 mm. 5 spear 57 microns; annules 68-72 ..... o .... o sphaerocephalum Taylor, 1936 Length ,50 mm.j spear 85 microns; annules W c ylindricum (Kir'ianova) Ftaski, 1952 lU. Total body annules 115 or less; spear kQ microns or more 16 Total body annules 1U2 or more; spear 25-Ul microns l5 15. Total body annules 11+2-156, angular on posterior edge; vulva on 11- 12th annule from terminus parvum Raski, 1952 Total body annules 200, rounded edges; vulva on 7 -8th annule from terminus zavadskii (Tulganov, 19l|l) Raski, 1958 16. Total body annules approximately UO boettgeri Meyl, 195U Total body annules 60 or more .......... ~. ] '. '. T .... 17 17. Total body annules 70 or more 19 Total body annules 60-65 18 18. First anniile irregular in outline or divided into h indefinite sub- lateral lobes; anus located on 3rd or Iith annule from terminus infome (Micoletzky, 1922) Taylor, 1936 Lips 6, large; anus on last annule very near terminus anura (Kir'ianova, 19U8) Raski, 1958 19. Spear length U8-67 microns 2k Spear length 70-86 microns 20 20. Sublateral lobes absent 22 Sublateral lobes present 21 21. Head bluntly rounded; amphids narrow, slit-like . xenoplax Raski, 1952 Head sharply tapered; amphids small, rounded quadricorne (Kir'ianova, 19U8) Raski, 1958 22. Total body annules 73-8U; length .53-. 72 mm .23 Total body annules 106-113; length .3U-.ii2 m.m . . . . teres Raski, 1952 23. Length .53 mm.; total body annules 73 ........ congolense (Stekhoven and Teunissen, 1938) Raski, 1952 Length .72 mm.j total body annules Qk beljaevae (Kir'ianova, 19)48) Raski, 1958 2kj Sublateral lobes absent, or if present are not prominent and flattened anteriorly . 25 Sublateral lobes prominent, flattened anteriorly presenting a trun- cated head lobatum Raski, 1952 25. First annule not well set off ' 26 First annule well set off; cuticle of larvae provided with rows of spines mutabile Taylor, 1936 35. 26. Length .30-,U5 mm. 5 head and tail not blunt-tmncate (tail of omatiira somewhat truncate) ....«..,..,.....■ 27 Length »60 mm.; head and tail both blunt-truncate rustlcum (Micoletzky, 1917) Taylor, I936 «9oeeeo«o*««eo 27^ Sublateral lobes absent . . « . o , . , 29 Sublateral lobes present. ...».o ».,,,... . 28 28. Anterior flap of vulva forming 2 definite points; larvae with longi- tudinal cuticular fringe; males unknown , « , . . . omatum Raski, 1958 Anterior flap of vulva bilobed, rounded; larvae without cuticular markings; males common ,= .,,.,..,,. , curvatum Raski, 1952 29. Lip region plain; amphids small and round or indistinct .30 Head with 6 indistinct lips; amphids large, oval; spear 53 microns; total body annules 70 , . . . tulaganovi (Kir'ianova, I9U8) Haski, 1958 30. Single gonad; vulva on 5-6th annule from terminus; amphids indistinct . e .»»..... o .... , . pullum (Kir'ianova, 19U8) Paski, 1958 Paired gonads; vulva on 8th annule from terminus; amphids small, rounded on 2nd and 3rd annules ...... tenuicute (Kir'ianova, 19U8) Raski, 1958 eo«fie«o« Genus Cacopaurus Thome, 19U3 (Key to species ) Three lines in the wing area; punctations in cuticle Four lines in the wing area; absence of punctations . . epacris Allen & Jensen, 1950 «eo9e09»9oee»«e Genus Belonolaimus Steiner, 19U9 (Key to the species ) Spear length I55u or more; tail length approximately 3 anal body diameters .«<,«,.,..,,..,...,. gracilis Steiner, 19U9 Spear length 13 5u or less; tail length approximately 5 anal body diameters . .,,,...» ....„,., , .longicaudatus Rau, 1958 Genus Dolichodorus Cobb, I9IU (Key to the species) 1. Spear less than 90u long. ,,.,,.,...,, similis Golden, 1958 Spear more than lOOu long ,..,,,,,.,.,..',,,,.,. 2 2» Mature female tail pointed; 3 incisures in lateral field '•""...c^o^. .......... heterocephalus Cobb, 191U Mature female tail rounded; k incisures in lateral field • •••<■»••»». «.«....«...... obtusus Allen, 1957 ^(■.. Genus Paratylenchus Micoletzky, 1922 (Key to the species from Tarjan, in press) 1. Males with distinct stylet 2 Males without stylet or males not observed 3 2. Anterior end narrow, tapering j spear U8-56u in length , goodeyi Oostenbrink, 19^3 Anterior end more normal; spear 30u or less. Protrusible spicula sheath bearing a posterior hook-like process ,,.. hamatus Thome and Allen, 1950 3. Stylet length greater than U5 U Stylet length less than U5 5 U. Larval stylet length as great as 67u, b= less than 3 , anceps Cobb, 1923 Stylet length 56u, b= greater than 3 ....... tanyoganis n. sp. 5. Maximum body length of population 310u or less. , . , , 6 Maximum body length of popiilation greater than 310u 9 6- Vulva usually situated at 70-80^ of body length; post-vulvar annules numbering about 70 minus eulus n. sp. Vulva usually situated at 80-86^ of body length; post-vulvar annules less than 70. . . 7 7. Post-vulvar uterus sac present. . . besoekianus Billy and Reydon, 1931 Post-vulvar uterus sac absent . 8 8. Male with protruding anal lips minutus Linford in Linford, Oliveira, and Ishii, 19U9 Male with normal anus elachisius Steiner, 19U9 9. Spear length 32-36u 10 Spear length 27u or less 11 10. Spear length 3U-36u, vulva at 82-83/^; spermatheca present; lip region not offset. nanus Cobb, 1923 Spear length 32u, vulva at 83-875^J spermatheca absent; lip region offset projectus Jenkins, 19?6 11. Short post-vulvar uterus sac present, b= U.3 , bukowinensis Micoletzky, 1922 Post-vulvar uterus sac absent 12 12. Tail short (c= 16. 5) J anterior end narrowing sharply near stylet guide; lip region strongly truncated. . curvitatus van der Linde, 1938 Tail relatively longer (c= 12.7); anterior end not narrowing sharply; lip region not as strongly triincated dianthus Jenkins and Taylor, 19$6 37. Family HOPLOUBaDAR (Filipj., l9Ui) Wieser, 1953 (Key to the subfamilies) 1. Females swollen 2 Females not swollen 3 2. Females swollen, pear to lemon-shaped; males with short bluntly rounded tail, anus subterminal. . . . HETERODERINAE Skarbilovich, 19147 P. 37 Females saccate to reniform, preserving some elongate tendencies; male tails conoid, anus not subterminal NACOBBINAE Chitwood, 19^0 P. 37 3. Females with one ovary PRATYLENCHINAE Thorne, 19)49 P.h6 (Contains one genus, Pratylenchus Filipj., 19314) Females with two ovaries HOPLOLAIMINAR Filipj ev, I9UI P.h7 Subfamily HETERODERINAE Skarbilovich, 19U7 (Key to the genera) 1. Vulva equatorial Meloidodera Chitwood, Hannon & Esser, 1956 (Contains one species M. floridensis Chit,, Hannon & Esser, 1956) Vulva terminal 2 2. Female body forming cyst; body packed with eggs Heterodera Schmidt, 1871 P. 38 Female body not forming cyst; body not packed with eggs Meloidogyne Goeldi, 1887 P.ij5 Subfamily NACOBBINAE Chitwood, 1950 (Key to the genera Chitwood, 1950) 1. Female with one ovary Nacobbus Thome & Allen, I9U4 P. 37 Female with two ovaries .... Rotylenchulus Linford & Oliveira, I9U0 ( Contains one specie^j R. re'nij'or/n is" Linford & Oliveira, I9I4O) . Genus Nacobbus Thorne and Allen, 19UU (Key to species after Thome and Schuster, 1956) 1. Adult female anteriorly spheroid or ovate, then slender, elongated; infective female with vulva-anus distance equal to about three times the tail length; male tail about one and one-half times as long as anal body diameter dorsalis Thorne and Allen, I9I4U Adult female soindle- shaped or irregular in form; infective female with vulva-anus distance one to two times the tail length; male tails about as long as anal body diameter 2 2. Adult female with strongly developed median bulb and corpus; infective female with vulva-anus distance about equal to tail length and with phasmids near middle of tail. . bataiformis Thorne and Schuster, 1956 Adult female without strongly developed median bulb and corpus; in- fective female with vulva-anus distance twice tail length, and phasmids near tenninus. aberrans (Thorne, 1935) Thorne and Allen, 19U'4 38. Genus Heterodera Schmidt, I87I (Key to the species prepared by A.L. Taylor) Notes This key is designed to facilitate identification of the species of Heterodera, using only characters of the mature cysts and their con- tents, that is, eggs with second stage larvae. Certain characters used in the key msy not be visible on other than fully mature cyets. 1. Body of cyst ovoid to globular, that is with posterior portion rounded and vulva not located on a distinct protuberance (figs, 1 and 2) Heterodera rostochiensis group #U 2. Basic element of pattern of outer layer of cyst wall at middle portion of cyst short zig-zag lines with little or no trace of regular trans- verse arrangement (figs. 7 and 8) sometimes modified to appear as net- work (fig. 12) 3 Basic element of pattern at outer layer of cyst wall at middle portion of cyst straight or wavy lines (figs. lU and I6) lines at right angles to axis of cystj sometimes broken by short oblique or vertical lines outer layer of cyst may have grainy appearance (fig. 18) • Heterodera cacti group 7 3. Mature cysts with dark bodies (brown knobs) and often sheaf-shaped object (lining of vagina) at posterior end (fig. ll). On immature cysts, these seldom visible, and then do not appear dark. • Heterodera schachtii group 8 Mature cysts without brovm knobs or sheaf-shaped object at posterior end • Heterodera gottingiana group 11 h» H. rostochiensis group . Cyst often ovoid, anus located at a transpar- ent spot on cyst so that anal and vulvar openings appear to be about the same size when seen by transmitted light (fig. 2l). Hyaline por- tion of larval tail much longer than stylet ... . Heterodera punctata Cyst ovoid to globularj anal opening appears much smaller than vulva opening (figs. 19 and 20). Hyaline portion of larval tail about the same length as stylet 5 5. Larvae very slenderj length about 39 times greatest widthj orifice of dorsal oesophageal gland about two-ttiirds stylet length posterior to stylet knobs. Heterodera leptonepia Length of larvae about 22 times greatest width; orifice of dorsal oesophageal gland about one-fourth stylet length posterior to stylet 6 6. Distance between vulva and anus about one and one-half tiraes diameter of vulva Heterodera rostochiensis Distance between anus and vulva about two and one-half times diameter of vulva Heterodera tabacum 7» H. cacti group. Hyaline portion of larval tail about as long as styletj stylet knobs concave anteriorly Heterodera weissi Hyaline portion of larvae of larval tail usually stiorter than stylet; stylet knobs convex anteriorly Heterodera cacti 8. H. schnchtii group. Cyst always with distinct punctation conGiLtinij; oi dots of uniform size but not in rows (fi(j. 25); brown knobs close- ly clustered around vulva. Hyaline portion of larval tail at leact one and one-hall' times lon^jer than stylet Heterodfja iTia.jor Cyst with or without punctation, mostly in rovfs if present; ui'oini knobs not closely clustered, around vulva. Hyaline portion of lai'vo.l tail about as long as stylet, 9 9. Average length of larvae ).|80 u or more 10 Average length of larvie about h60 u Heterodera schpchtii 10, Average length of larvae [l8U u Heterodera ''lyc inGs Average length of larvae i>02 u. Heterodera trifolii Average length of larvae 5l8 u, . . . Heterodera schachtii galeo p sidis 11, Average length of larvae U1I4 u Heterod era cru ci rerao Average length of larvae hS\\ u « Hetei"odcr-i c nrotae Average length of larvae i47l4 u Heterodera gottin'iana Average length of larvae i;05 u Heterodera hwiu lL /Average length of larvae hPS u Heterodera fici Plate I, Shapes of cysts of Heterodera species. Fig. 1. H. rostochiensis . Fig, 2, H. punctata . Fig, 3, H. schachtii Fig, U, H. avenae . Fig, 5. H. weissi, Fig. 6. H. cacti, Plate II, Cyst patterns of Heterodera schachtii and related species. Figs. 7 and 8. Zig-zag line pattern near middle of cysts of H, trifolii and H. schachtii respectively. Fig. 9. Pattern at junction of neck and body of cysts of H. schachtii . Fig. 10. Pattern near vulva of cyst of H. gottingiana . Fig. 11, Sheaf -shaped object and dark bodies at lower end of cyst of H, schachtii . Fig. 12. Netx-iork pattern, a variation of that shown in Figs. 7 and 8. Magnification of figure 11 is about 200X, all other about UlOX. Plate III, Cyst markings of Heterodera weissi and H. cacti . Fig. 13. Lower part of cyst of H. cacti . Fig, 1I4, Pattern near middle of cyst of H, weissi . Fig. 15, Pattern at junction of body and neck of H, weissi . Fig, I6, Pattern near middle of cysts of H, cacti . Fig. 17, Loxjer end of cysts of H, cacti showing anus. Fig, 18, Grainy appearance of cyst of H. cacti . All about UlOX, Plate IV, Cyst patterns and punctation of Heterodera rostochiensis and H, punctata . Fig. 19. Pattern at vulva and anus of H. rostochiensis . Fig, 20. Same as Fig. 19, but with deeper focus to show punctation. Fig, 21. Anal and vulvar openings of cyst of H, punctata . (Cyst split in process of prepara- tion). Fig, 22. Pattern at about middle of cyst of H. rostochiensis . Fig, 23. Pattern of upper part of cyst of H. punctata . Fig, 2U, Punctation of H. rostochiensis . All about UIOX. Plate V, Cysts and eggs of Heterodera species. Fig, 25, Punctation of cyst of H, avenae , Fig, 26, Punctation and pattern of cyst of H, hujnuli. Fig, 27. Punctation of cyst of H. trifolii . Fig. 2jr, Punctation of egg shell of H. cacti. Fig. 2 080 Fig. 3 ^^ Fig. 4 lO Fig. 5 Fig. 6 '^^^f^^^^m ^■\^ I - -1^^^:' : fmm '.» * i"-7»v;-"-'i*jDiaas; m I ■"m^ ,-.vl *».;.»*'*■ r3 5. Striations around terminus of tail, .. pratensis (de Man, I880) Filipjev, 193U No striations around terminus of tail 6 6. ^ter margins of cephalic framexjork prominent, extending posteriorly about two body annules; tail bluntly rounded thome i Sher & Allen, 1953 Outer margins ox cephalic framework normal, . 7 7. Vulva 68-76 per cent; tail tapering to narrow rounded terminus, . • 8 Vulva 78-8U per cent 9 8. Three annules on lip region; males absent zeae Graham, 19^1 Four annules on lip region; males numerous « goodeyi Sher St .Ulen, 1953 9. Postuterine branch short, length about equal to body width at vulva; tail broadly rounded, , penetrans (Cobb, 1917) Filipj, & Stekh., 19i|l Postuterine branch long, two or three times body width at vulva; tail tapering to narrow rounded terminus . . vulnus Allen and Jensen, 1951 Species Inquirendae: P, sacchari (Soltwedel, I888) Filipjev, 1936 Dolichodorus heterocercus Kreis, 1930 Other species: P, coffeae brasiliensis Lordello, 1956 £► neglectus (Rensch , .192!4) Loof , 1957 _P, pratensis bicondatus Heyl, 1953 P. pratensis tenuistriatu s Meyl, 1953 P, tvunidiceps Merzheyevakaya, 1951 U7. Subfamily HOPLOLAIMINAF. Filipjev, 193U (Key to the genera) 1. Phasmids extremely large, scutellum-like 2 Phasmids normal, small, pore-like 3 2. Transverse striae continuing across lateral fields; spear knobs anteriorly furcate and pointed Hoplolaimus Daday, 1905 ^'hl Central field of lateral field smooth, without transverse striae; spear knobs rounded Scutellonema Andrassy, 19^8 P'^8 3. Esophageal glands forming a distinct bulb Tylenchorhynchus Cobb, 1913 ^'h9 Esophageal glands free in body cavity, overlapping intestine ... I4 il. Tail length approximately equal to anal body diameter $ Tail length at least twice as long as anal body diameter. 7 5» Dorsal gland orifice usually less than 1/3 or more of stylet length froi/i base of stylet 6 Dorsal gland orifice 1/3 or more of stylet length from base of stylet length from base of stylet Helicotylenchus Steiner, 19U5 P»?2 6. Lip region longitudinally striated; gubemaculum bear titillae Rotylenchus Filipjev, 1936 ^•^^ Lip region with transverse annules only; gubernacultim without titillae Gottholdsteineria Andrassy, 1958 P'53 7. Esophageal glands extending far back over intestine Radopholus Thome, 19U9 ^'53 Esophageal glands only slightly overlapping intestine Pratylenchoides Winslow, 1958 (Contains a single species P. crenicauda Winslow, 1958) Genus Hoplolaimus Daday, 1905 (Key to the species) No lateral field except at each end of body where annules are slight- ly interrupted in lateral line proporicus J. Goodey, 1957 Lateral fields present tylenchiformis Daday, 1905 sjn: Hoplolaimus coronatus Cobb, 1923 Genus Rotylenchus Filipjev, 1936 (Key to the species) Phasmid located slightly anterior to anus robustus (de Man, I876) Filipjev, 1936 syn: Tylenchus robustus de Man, 1876 Tylenchorhynchus robustus (de Man, I876) Micoletzky, 1929 partim Hoplolaimus uniformis Thome, 19U9 Phasmid located 2 anal body diaraeters anterior to anus ,gracilidens (Sauer, 1958) Sauer, 1958 U8. Scutellonema Andrassy, 1958 (Key to species modified from Golden, 1956) 1. Phasniids not opposite each other, location of anterior one being at avera'^e of 79^ of body length and posterior one at an average of 86^; lips of vulva protruding christiei (Golden & Taylor, 1956) Andrassy, 1958 (syn. Rotylenchus christiei Golden & Taylor, 1956) Phasmids opposite each other and located on tail or in vicinity of anus; lips of vulva not orotruding 2 2. Tail as long as or longer than anal body diameter; head with seven or more annules 5 Tail much shorter than anal body diameter; head with five annules or less 3 3. Lateral field aerolated in esophageal region; five annules on head, k Lateral field not aerolated in esophageal region; three annules on head, rarely four coheni (j. Goodey, 1952) Andrassy, 1958 (syn. Rotylenchus coheni, J. Goodey, 1952) U. Opening of dorsal esoohageal gland is 1/9 of stylet lenruh from base of stylet brachyurum (Steiner, 1938) Andrassy, 1958 (syn; Rotylenchus brachyurus Steiner, 1938) Opening of dorsal esophageal gland is about 1/3 of stylet length from base of stylet boocki (Lordello, 1957) Andrassy, 1958 (syn: Rotylenchus boocki Lordello, 1957) 5. Stylet knobs anteriorly flattened or slightly concave bradys (Steiner & Leriew, 1933) Andrassy, 1958 (syn: Hoplolaimus brgdys Steiner &■. LeHew, 1933) Stylet knobs ovoid, anteriorly convex blaberum (Steiner, 1937) Andrassy, 1958 (syn: Rotylenchus blaberus Steiner, 1937) Wj. Genus T;/'lcnchor]';;niclaii: Cobn, 191-3 (Key to the sp eci e s ) 1. Cuticle marked by lonjjitudinal striae 2 Cuticle not marked ry lontjitudinal striae • 7 2. Lateral field marked by I4 lines 3 Lateral field marked by 6 lines U 3. Lip re£;ion bearing 3 or U annules c la^^on i Steiner, 1937 Lip region bearing 6 or 7 annules lamelliferus (de Man I88O) Filipjev, 1936 I4. Annules extending around terminus of tail tessellatus J. B. Goodey, 19^2 Annules not extending around terminus of tail 5 5« Less than 35 longitudinal striao at middle of body . .6 About 60 longitudinal striae at middle of body quad r ifor Andrassy, \9Sh 6. Lip region set off by c mstriction lenorus Brown, 1956 Lip region continuous id.th body contour ornatus Allen, 1955 7. Lateral field marked by i; lines 8 Lateral field marked by 5 lines 2I4 Lateral field marked by 6 lines 26 8. Annules exterri.ing around terminus of tail 9 Annules not extending around terminus of tail lU 9. Lip region set off by constriction, dubis (Butschli, 1873) FUipiev, 1936 Lip region continuous body contour. , 10 10, Lip region bearing 6 or 7 annules; tail cylindrical, bluntly rounded . 11 Lip region bearing i; or 5 annules; tail tapering conoid ,.,,,., , eremicolus Allen, 1955 11, Lip sclerotization heavy, conspicuous ,12 Lip sclerotization faint, inconspicuous .,.,13 12, Tail length about 1 anal body diameter; phasmids opposite anal opening brevicaudatus Hopper, 1959 Tail length over 2 anal body diameter; phasmids at middle of tail • • Jiagni Cauda (Thorne, 1935) Filipjev,1936. 13, Tail less than 3 X anal body diameter parvus Allen, 1955 Tail more than 3 X anal body diameter maxicais Allen, 1955 50, llt» Lip rc:;^;ion continuous x-ath body contour «.«.»........ .11; lip re^jion set off by constriction or depression, . . . , . » . . . 22 iSm Lip rejion bearin;j 2 annules nudus Allen, 1955 Lip bearinij more th.-m 2 annules l6 16. Lip sclerotization f nint, inconspicuous 17 Lip sclerotization strong, conspicuous, 20 17. Tail bearin;^ 10 to l5 annules ,- 18 Tail bearing 20 to 27 annules . , 19 18. Lip region bearing 5 annules; spear 15-17 as long. . clarus Allen, 1955 Lip region bearing 3 annules; spear 18-20 as long eniTin^i Hopper, 1959 19. Lip region bearing 5 annules; tail subcylindrical . striatus A3.1en,1955 Lip region bearing 3 annules; tail snriiewhat clavate ....' .« martini Fielding, 1956 20. Spear less than 20 u long . manubriatus Litvinova, 19ii6 Speai' more than 20 u long 21 21. Spear not more than 31 u long, tail bearing 50 annules • • kegenicu s Litvinova, 19li6 Spear more than 31 u long, tail bearini^ i;5 annules , galeatus Litvinova, 19ii6 22. Spear more than 20ulong, lips rounded, sclerotization conspicuous • • ••.... cylindricus Cobb, 1913 Spear less than 20ulong, lips broadly rounded, sclerotization faint. 23 23. Lip region bearing 6 annules; tail conoid, bearing approximately l6 annuals latus Allen, 1955 Lip region bearing 3 annules; tail somewhat clavate, bearing approxi- mately 26 annules martini Fielding, 1956 2h. Tail about 2 X anal body diameter, beai-ing less than 25 annules . . • acutus Allen, 1955 Tail about 3 X anal body diarrteter bearing more than 25 annules. . . .25 25. Tail bearing about 32 annules, terminal annule not enlarged capitatus Allen, 1955 Tail bearing about lj2 annules, terminal annule enlarged ..,» , acti Hopper, 1959 26, Annules extending around terminus of tail 27 Annules not extending around terminus of tail 31 27. lip region set off by constriction or depression. . Iqjtus Allen, 1955 Lip region not set off by constriction or depression 28 28, Lip sclerotization well developed, conspicuous, . macrmnis Allen, 1955 Lip sclerotization faint, inconspicuous 29 51. 29. Spear more than 23u long »» ..,...»,. , , obscurus Allen, 1955 Speai' less than 22u long aial 61 .norphism; esophageal gl^rnds ventrally located; length more than l.hmid h 2, Lateral field marked by I4-7 lines; annules extending around terminus of tail inequalis Sauer, 1958 Lateral field marked by U lines only; annules not extending around terminus of t^il .„ 3 3, Tail length 2\ times anal body diameter; ,c=ll4-l6; terminus blunt, . . neosimilis Sauer, 1958 Tail length U times anal body diameter, c=10; terminus conoid or irreg- ular similis (Cobb, 19l5) Thorne, 19h9 h» Spear length more than LtOu lavabri Luc, 195? Spear length less than 30u, . g racilis (de Man, I88O) JILrsclmann, 1955 syn: jLgas (Andrassy, 1951i) Hirschman, 1955 Others: n^oryz.ae (n. Breda De Haan, 1902) Thorne, 19^9 and R. zostcricola (Allgen, 193li) Allen, 1955 appear to be identical to ic, tfracilis ^md arc considered as sjTnonyms in this work. ^h. Farpily TYI.^NCmiLIDAK Raski, 1957 (Key to subfamilies from Raski, 19 37) Excretory pore located posterior to normal position near nerve ring; male stylet degenerate. . . Subfamily TYLENCHULINATi; Skarbilovich, 19U7 P. 51; Excretory pore normal, near nerve rin'^; male stylet lacking Subfamily SPHA'-'KUNHviatINAR Raski & Sher, 1952 P.5U Subfamily TYLMCKUlJiJAE Haski & Sher, 1952 (Key to genera) Lip region with circumoral elevation; excretory core not closely approximated to vulva Trophotylenchulus Raski, 195? (Contains a single species, T. floridensis Raski, 195?) Lip region without circumoral elev^ation; excretory pore closely approximated to vulva Tylenchulus Cobb, 1913 (Contains a single soecies, T. semipenetrans Cobb, 1913) Subfamily SPHAP^P^ONFWATINA^ Raski & Sher, 1952 (Key to genera) Female spiral, thickened Trophonema Raski, 195? (Contains a single species, T. arenari'.im (Raski, 1956) Raski, 1957) Female spherical Sphaeronema Raski & Sher, 1952 P.5U Genus Sphaeronema Raski S- Sher, 1952 (Key to species) Lip region with circumoral elevation. . minutissimum J.B. Goodey, 1958 Lip region without circumoral elevation californicum Raski & Sher, 1952 55. FM.iily TYi,L.Ni:iIj;D.\E Ocrlcy, I8u0 (Key to the subfaiiiilies adopted from 'i'liornc, 191)1} 1, Hetacorpus fusiform uxth distinct internal sclerotization ...... TILIi-lC;u;rf.'\i; (de han, I876) iiicol., 1922 P.5.V Metacorpus not b-lbcir, xjith little or no internal sclerotization. . .2 2, Basal esophageal bulb bearing 9 stem-like basal extension " , PAUR0D01.iTIiI/^.E Thorne, I9I4I P.b5 Basal esophageal bulb not bearin^^ a stem- like basal extension ... ,3 3, Head framework octagonal, esophageal glands overlapping intestine to a greater or lesser extent l\iEOTILl:;NGHl!-:AE Thome, I9I4I P. 55 Head framework hexagonal, esophageal glands not overlapping intestine NOTlIOTYLENCmNiUL Thorne, I9I4I P. 55 Subf ainily P.IURODONTINAE Thorne, 19l4l (Key to the genera from Thorne, 19 Ul) 1, Spear knobs symmetrical Paurodont us Tl-iorne, I9UI P. 56 Spear knobs asynmfitrical, the ventre submedi an knobs much larger than the dorsal knob Stict ylus 'Iliorne, 19iil ^-56 Subfamily KOTHOTYLiJ^IGIiimE Triorne, I9UI (Key to tte genera from Thorne, 19 ill) 1, Cuticle abnormally thick and deeply striated. . . . Thada Thorne, I9I4I P.56 Cuticle not abnormally thick, finely striated 2 2. Speai^ with tylenchoid basal knobs .... . Nothotylenchus Thorne, 19lil P.56 Spear with flange-like basal projections, . . . Beleod orus Thorne, 19lil P'57 Subfamily NEOTYLENCHINAE Thorne, I9UI (Key to genera from Thorne, I9UI) 1. Esopha,^us base fused with intestine, not set off in any manner Hexatylus Goodey, 1926 P. 58 EsoDhagus base set off, bulb-like or with greatly developed glands. .2 2. Intestine joining esophagus just back of nerve ring; glands lying free in the body cavity Deladenus Thorne, I9UI P. 58 Intestine not joining esopha-;us near nerve ring; glands -within a basal bulb Neotylenchus Steiner, 1931 P. 57 9^. Genus Paurodontus Thorne, 19^1 (Key to the species frcan Thorne, 19Ul) 1. Length about 0.7 mm gracilis Thorne, I9UI Length about O.U inm 2 2. Terminus subacute, tail somewhat arcuate densus Thome, I9UI Terminus acute, tail rather straight. ~~. \ T 3 3. Head about half as wide as base of neck apiticus Thome, 19i;l Head almost as wide as base of neck niger Thorne, I9UI Genus Stictylus Thome, I9UI (Key to the species) 1. Tail length equal to 1/2 the vulva-anus distance asymmetricus Thome, I9UI Tail approximately equal to the vulva-anus distance 2 2. Tail cylindroidj terminus blunt, almost flat. . . mycophilus Ruhm, 1956 Tail tapering; terminus bluntly conoid to conoid 3 3. Tail terminus dorsally convex-conoid psuedobtusus Ruhm, 19^6 Tail uniformly conoid ~~. '. ~. TT .... U U. Basal bulb of esophagus ovate with triquetrous lumen obtusus Thorne, I9UI Basal bulb of esophagus elongate, conoid; lumen not triquetrous . . 5 5. Posterior uterine sac present . . . stammeri ("rfachek, 1955) Ruhm, 1956 Posterior uterine sac absent pini (Fuchs, 1929) Ruhm, 1956 Genus Thada Thorne, I9UI (Key to the species from Thome, I9UI Cuticle marked by only transverse striae striata Thome, I9I4.I Cuticle marked by both transverse and longitudinal striae cancellata Thome, I9UI Genus Nothotylenchus Thome, I9UI (Key to the species modified from Thorne, I9UI) 1. Basal esophageal bulb elongate-cylindrical cylindricollis Thorne, I9UI Basal esophageal bulb tapering 2 2, Terminus rounded, incisures 6 affinis Thorne, 19U1 Terminus acute, incisures U 3 ?7- 3. Corpus of esopha-us with ovoid valvular apparatus drymocolus Ruhm, 19^6 Corpus of esophagus v;ithout ovoid valvular apparatus acris Thome, 19U1 Genus Beleodorus Thome, 19U1 (Key to the species Thome, 19Ul) Terminus of female tail acute thylactus Thome, I9UI Terminus of female tail clavate clavicaudatus Thome, I9UI Genus Neot.ylenchns Steiner, 1931 (Key to species after Thome, 19l;l) 1. Vulva almost terminal obesus Thome, 193U Vulva well in front of terminus 2 2. Posterior uterine branch present 3 Posterior uterine branch absent 5 3. Tcil uniformly cylindrical from anus tc bluntly rounded terminus j with peg-like terminal process * . . italicus Meyl, 195U Tail conoid; without terminal process .,.„ Ij. U. Tail length less than 2.0 anal body diameters j uniformly conoid to acute teiminus latus Thome, I9UI Tail length more than 2.5 anal body diameters; latter 1/5 cylindrical with rounded terminus , . . . thomei Meyl, 195U 5. Female tails elongate conoid, a= 8-10 6 Female tails not elongate conoid, a= 15-20 .• 7 6. Oocytes arranged tandem in ovary acutus Thome, I9UI Oocytes massed in ovary . . . copropha^'-us (Goodey, 193^) Thome, 19i4.1 7. Teiminus acute 8 Terminus blunt, rounded . . ' 9 8. Lip region set off by constriction; male with normal spicula and spear consobrinus (de Man, I906) Filipjev, I936 Lip region not set off; male with degenerate spicula and without spear albulbosus Steiner, 1931 9. Bursa enveloping tail; female tail sub-cylindroid, very blunt intermedius (Christie, 1938) Thome, I9UI Bursa not enveloping tail; female tail conoid to small, blunt terminus arcuatus Thome, 19U1 9^, Genus Deladenus Thome, 19)il (Key to species from Andrassy, 1957 1. Postvulvar uterine sac present, well developed sac catus Andrassy, 195U Postvulvar uterine sac absent or only slightly developed 2 2. Vulva-anus distance considerably shorter than tail length 3 Vulva-anus distance as long or longer than the tail length U 3. Vaginal wall thickened, uterus with sraall postvulvar part; tail acute aridus Andrassy, 19^7 Vaginal wall thin, utems without postvulvar part; tail terminus rounded durus (Cobb, 1922) Thorne, 19U1 U. Vagina very short, much smaller than the corresponding body diameter; tail terminus digitate norimbergensis Phihm, 1956 Vagina about as long as the corresponding body diameter; tail obtusely rounded obesus Thome, I9I4I Genus Hexatylus Goodey, 1926 H. boettgeri Meyl, 195U H. vigissi Skarbilovitch, 1952 H. viviparus Goodey, 1926 59. Subfamily TYL^^CHINAt^ (de Man, 1376) Ilicol., 1922 (Key to the genera) 1. Head anaed vfith setae 2 Head not armed with setae 3 2. Cuticle with transverse striae only ^utylenchus Cobb, 1913 (Contains a single soecies E. setifersis fCobb, 1893) Cobb, 1913) Cuticle with transverse and longitudinal striae . .A tylenchus Cobb, 1913 (Contains a single species A. decalineatus Cobb, 1913) 3. Ovary one U Ovaries two 12 U. Base of spear furcate Chitinotylenchus Micol., 1922 P.60 Base of spear amalgamated, with or without basal knobs 5 5. Esophageal glands overlapping intestine 6 Esophageal glands in form of basal bulb, not overlapping intest- ine 7 6. Posterior portion of tails of both sexes characteristically hooked (Habitat marine) Halenchus Cobb, 1933 P.60 Posterior portion of tail not hooked. (Habitat terrestrial) Pseudhalenchus Tarjan, 1958 P.60 7. Female with tail short, rounded and cuticle swollen Trophurus Loof, 1956 P.60 Female with cuticle on tail not swollen 8 8. Female tail attenuated 9 Female tail conoid, subacute 10 9. Median bulb in first half of esophagus. . . . Tylenchus Bastian, 1865 P. 61, Median bulb in latter half of esophagus . . . Psilenchus de Man, 1921 P. 66 10. Female body obese , Anguina Scopoli, 1777 P.6U Female body slender 11 11. Lateral lips enlarged Sychnotylenchus , Ruhm, 1956 P.6U Lateral lios not enlarged Ditylenchus Filipj., 193U P. 65 12. Female tail attenuated Psilenchus de Man, 1921 P. 66 Female tail short, pointed or subacute. . . Tetylenchus Filipj., 1936 P. 67 Others: Paranguina Kirjanova, 1955 ^n. Genus Chitinotylenchus Micoletzky, 1922 Genotype is C. paragracilis (Micol., 1922) Filipjev, 1936 and. is in- adequately described. The only other species is C. annul atus (Cassidy, 1930) Filipjev, 1936. Genus Halenchus Cobb, 1933 (Rey to the species) Stylet 1/8 - 1/9 of total esophageal length; postanal parts of the caudal alae less than 1/U tail length mediterraneus (Micoletzky, 1922) Cobb, 1933 Stylet 1/13 - 1A5 of total esophageal length; postanal parts of the caudal alae more than 1/U tail length fucicola (de Man & Barton in de Man, 1892) Cobb, 1933 Species inquirenda: H. mexicanus Chitwood, 1901 Genus Psaudhalenchus Tarjan, 1958 (Key to the species ) Four lines in lateral field minutus Tarjan, 1958 Six lines in lateral field anchilisposomus Tarjan, 1958 Genus Trophurus Loof , 1956 (Key to the species) 1. Length greater than 1 mm.; stylet 19-21u; cuticle on tail thickened but not swollen imperiolis Loof, 1956 Length less than 0.8 mm; stylet l[t-l6u; cuticle on tail thickened and also swollen 2 2. Terminal esophageal bulb constricted in or behind the middle sculptus Loof, 1956 Terminal esophageal biilb not constricted in or behind the middle minnesotensis (Caveness, 1958) Caveness,1959 syn: Clavaurotylenchus minnesotensis Caveness, 1958 r-^1. Genus Tylen^jp^ Bastian, l86i> (Key to the subgenera froia Andras.'^y, 19%) 1. Cuticle well annulated; spear heavy and well knobbed; infr,tacorpus round 2 Cuticle finely annulatedj spear weai<:ly developed; metacorpus oval . . 3 2. Head hardly offset, tail relatively short, ventrally hooked Tylenchus (Bastian, l865) Andrassy, 195U Head well offset, Annules remarkably pronounced, tail thin and atten- uated A^lenchus Andrassy, 195U 3. Average sized species. Annules clear'. Bursa well developed. • « » . Filenchus Andrapsy, 19514 Small species. Annules very fine. Bursa rudiraentary L elenchus Andrassy, 19Sh Subgenus Tylenchus (Bastian, 186^) Andrassy, 19$h (Key to tlie species from Andrassy, 195U) 1. Cuticle marked with annules ;md lon^p-tudinal fields 2 Cuticle mthout lont;;itudinal ridt^es 3 2, I8-2U longitudinal ridges; postvulval uterine sic ver.v sJiort or tiiiss- ing; males unknown costatus de Han, 1921 Always only 10 longitudinal ridges; postvulval uterine sac about 2 body ^^7idths long; males appear to be as niuaerous as females ...... sachsi HirEcl"mia.nn, 19 3. Spear very delicate, not (or hardly noticeably) knobbed Ii Spear strong or xjeak, in the latter cnse the knobs are evident. . . .8 U» Bursa very rudimentary; small animals (about O.U mrii) 5 Bursa normal, well developed; large animals (over O.I4 mm) .6 5. Tail finely attenuated, ver;- long {r.= 3 •1-3. 5); spear very delicate, 3.5-U.O u infirmns (Andrassy, 1952) Andrassy, 19?U Tail not so long, shorter (c=i;. 8-6,5); spear longer, G-9 u long . . . minutus Cobb, 1893 6. Cuticle very coarsely annulated; gubernaculuia obscure vreidenbachi RaJuii, 192h Cuticle finely annulated; gubcrnaculum clear 7 7. Cuticle finely annulated ( annul e vjidth 0.9-1.2u); tail long and thin (c = 3.7-)4.5) liliforMis Butschili,l873 Cuticle annules wide and even ( armule width 1.7-1.8 u); tail shorter not so finely attenuated (c = 5.3-10.0) p olyh;^'}nus Stetner (\ .llbin, I9U6 ^^2. 8. Body ver) thin (a = hO - 60). , v 9 Body not so thin ( a = 38 highest) 10 9. Body vei'y larj^e (l,3'-1.7 v,iiii,)j spear lon^i; tail of norwal len^^th (c =9-10.3) ^rc-iciloides liicolet'/ky, 192^ Body riuc; smaller (O.I:-0.66 iiua.); sjoe'u shorter; tail very attenuated (c = 2.7-I1.O) IS^^PPPF?. <^e i'ian, 1880 10, Bursa ru''.iiiaentary or inc'istinjnishablc ,. 1 Bursa normally developed (only few.iles kncm for dirolexus and orbus). . . . . . . TTTl} 11. Larj;er species (O.Y mra. )j cuticle well snnulated. Micolet2,kyi Andrassy, 195U Smaller species (up to O.Iil mm.); cuticle very finely annulated . . 12 12, Bursa rudimentary but apparent; tiubernaculum present; tail markedly attenuated, filiform dis cr eprrs Ajidrassy, 195h Bursa and ^ubernaciilum .ndistinijuishable; tail shorter, not so thin . aberrans Altherr 13. Tail ventrally hooked, not j inely acuiainate, terminus hooked. . . . lU Tail mostly strongly attenuated, finel;>- acuminate, not ventrally hook- ed 16 lij. Tail almost cylindi'ical, gradually tapcrin^, alae v;ith 3 inner ricJ^es intactus hirjanova, 15^1 Tail slimmer, more thin, alr'c with 2 inner ridges 15 13. Vulva at mid-body (i,8,J-50,J)5 spear 10-llu long kirjanovae (Kirjanova, 1951) Andrassy, 195^4 Vulva in latter third of body (6^-70/^); spear 15.8-17.6 u long. , . , .• davainii Bastian, l865 16. Annules very striking; smaller species (up to 0.6 mm.) 17 Annules finer, not so distinct; larger species (over 0,7 mm.) , . . I8 17. Wall of ttie vagina greatly thickened; posterior uterine-sac missing; spear roundly knobbed; annule vddth 1.7 u . , . . agricola de Man, I88I4 Wall of vagina without unusual thickening; posterior uterine sac pre- sent; spear longitudinal knobbed; annule width 0.9-1.2 u bryophilus Steiner, I91U 18. Tail very thin, filiform (c = I4); metacorpus powerful and round . . . thornei Andrassy, 195U Tail shorter, not so attenuated (c = 6-12); metacorpus oval . , . , 19 19. Esophagus very thin, metacorpus very weak; spear well knobbed; body analler (6.72-0.79 orbus Andrassy, 19i)U Esophagus bigger, metacorpus well developed; spear more weakly knobbed body larger (0,9-1.1 mm,),' dupieyus (Hagem'eyer & Allen, 1952) Andrassy, 195U ." -t Genus Tylenchus Bat^tian, l86i> (Key to the species ad;Apted l.iy Allen, 1950 iro:ii iilipjev f; Stekhoven, 19la) 1, Tail length 5 or more times nnal di-jneter 2 Tail length not exceeding U-l/2 times anal body diameter 11 2, Body width at least 2.5 per cent oi bo(iy length 3 Body width less tlian 2 per cent ox body lengtli 10 3, Length usually exceeding 0.5 mm h Length usually less than 0.5 mm 9 \x» Spear at least l/7 oi osophageal length 5 Spear less than l/7 of osophageal length. .8 5« Tail length 5 times anal body diai.ieter uniTormis Cobbj 1693 Tail length 7 times anal body diameter davainei Bastian, 1865 6, Tail length not exceeding 7 times anal body diameter. 6 Tail length exceeding 10 times anal body diameter 7 7. Tail length 11 times anal body diameter .... ema rginatus Cobb, 1893 Tail length 12 times anal body diameter .... agricola de Man, 1881; 8, L(ingitudinal striations present co status de Han, 1921 Longitudinal striations absent filiformis ButsclHi, 1873 9. Cuticle coarsely annulated. . . bryophll us Steiner, 19 lU Cuticle finely annulated minutus Cobb, l893 10. Tail length l8 times anal body diameter .... leptosoma de Man, 1880 Tail length 5 times anal body diameter foliicola Zimra., 1902 11. Adults 1.0 iiira, or more in length. "12 Adults less tlian 1.0 nm. in length ...,13 12. ^ = about 30 askenasyi Butschli, l873 a. = about 50 to 60 gracilioides Micol., 1925 13» a = 30 or less lU a = 35 or more. brevicaud a Micol., 1925 lii. Spear equal to l/9 - l/l2 of esophageal length. terricola Bastian, 1865 Spear equal to l/Ii - l/5 of esophahreal length l5 15» Spear 2-1/2 times as long as vddth of liead at base.farTrdcki Ralmi, 1921; Spear 1-1/2 times as long as iiridth of head at base.""; . . weidenbaclii Rahm, 192h %. Genus An_^uina Scopoli, 1773 (Key to the species tiodii'ied fiom Filipj. -i^ Stekh., 19lil) 1. Median esophageal bulb absent cecidoplas tes (Goodej/, 193U) l^'ilipjev, 1936 Median esophageal bulb present \ 2 2, Median bulb not distinct riiLcrolaenae (Fawcett, 1938) Filipj. & Stekh., 19UI Median bulb distinct 3 3« Tail obtusely rounded at apex; head not offset. •• •.• tritici (Steinbuch, 1799) Filipjev, 1936 Tail pointed at tip U h' Tail regularly conical 5 Tail swollen, although this swelling is sometimes feeble 8 5. Bursa quite wrapping in the tail; esophageal glands not enlarged; posterior esophageal bulb not swollen ... . spermophaga Steiner, 1937 Bursa almost wrapping in the tail 6 6, Esophageal glands much enlarged, posterior esophageal bulb strongly swollen; spicula flat, widest in the middle, slightly arcuate .... agrosti s (Steinbuch, 1799) Filipjev, 19 36 Esophageal glands hardly swollen; no definite posterior bulb 7 7. Spicula regularly tapering to 1he tips tumefaciens (Cobb, 1932) Filipj. & Stekh., 1911 Spicula widened in the middle . austral! s Steiner, 19 UO 8, Spicula distinctly longer than anal diameter, provided with a narrow sheath graminis (Hardy, 18^0) Filipjev, 1936 Spicula shorter than anal diameter, very broad. ...... inillefolii (Low, I87I1) Filipjev, 1936 Other species: A., balsamophila (Thorne, 1926) Filipjev, 1936 A. pustulicola (Thorne, 193^) Qoodey, 1951 Genus Sychnotylenchus Ruhm, 1956 (Key to species) 1. Length more than 1.0 mm; tail conoid; terminus rounded to pointed ulmi Ruhrrt, 1956 Length less than 1.0 mm; tail cylindroid; terminus truncate intricati Ruhm, 1956 65. Genus Ditylenchus Filipjev, 193U (Key to the species modified from Filipj. & Stekh. 19)4l) 1. Tail pointed at the end in both sexes 2 Tail obtusely rounded at the end in the female sex 16 2. Body slender (a=32-60); body width 1.7-3.2^ of body length 3 Body plump (a=20-3l) : body width 3.3-^'^ of body length 8 3. Bursa rudimentary darbouxi (Cotte, 1912) Filipj., 1936 Bursa copulatrix well developed h k» Esopha.-^us well developed; gubemaculim in profile very thin, but long intermedius (de l^an, 1880) Filipjev, 1936 Esophagus in adult form, especially in males, is weak, not strongly muscular; gubemaculum short and thj ck 5 5. Bursa ending a short distance in front of tip of tail 6 Bursa ouite wrapping in the tail . TJrocerus (Bally & Reydon, 1931) Filipjev, 1936 6. Lateral field with h incisures; tail terminus acute djpsaci (Kuhn, 18^7) Filipjev, 1936 Lateral field with 6 incisures; tail terminus finely rounded. ... 7 7. Postvulvar uterine sac about 2|- times Amlvar body diameter in lenr^th destruct or Thome, 19^45 Postvulvar uterine sac less than 2 times vulvar body diameter in length myceliophar;us J, Goodey, 1958 8. Bursa not quite wrapning in the tail 9 Bursa quite wraoping in the tail 15 9. Vulva (=V) between 75-85^^ of body length 10 Vulva between 86-96^ of body length 12 10. Spicula provided with a thick sheath; body long; V=71-8l^ radicicola (Greeff, 1872) Filipjev, 1936 Spicula not provided with such a sheath 11 11. Heads of spicula hardly offset; male tail about 2 l/3 anal body diam- eters long phyllobius (Thome, 193U) Filipjev, 1936 Heads of spicula distinctly offset, barbed; male tail about 3^ anal body diameters long angustus (Butler, 1913) Filipjev, 1936 12. Vulva far posterior at 96^ of body length pustulicola (Thome, 193ii) Filipjev, 1936 Vulva between 86-905? ' 13 13. Body length of both male and female less than lOOOu arboricolus (Cobb, 1922) Filipjev, 1936 Body length over lUOOu l)i 66. lU. Postvulvar uterine sac ahsentj bursa extending far down tail graminophila Goodey, 1933 Filipjev, 1936 Postvulvar uterine sac present; bursa extendinf^ about half way dovm the tail balsamophilus (Thorne, 1926) Filipjev, 1936 15. Median esophageal bulb inconspicuous; male tail with mucro; male slightly longer than female, the former not surpassing 1 mm. ..... durus (Cobb, 1922) Filipjev, 1936 Median esophageal bulb distinct; male tail without mucro; female distinctly longer than male, having a length of 2.5 mm . pinophila (Thome, 1935) Filipjev, 1936 16. Tail short, only l|- times as long as anal body diameter 17 Tail medium, 2^ timas as long as anal body diameter 18 17. Head not distinctly offset; spear 1/10 of esoohageal length ,....,,..... majo r (Fuchs, 1914) Filipjev, 1936 Head distinctly offset; spear 1/15 of esophageal length ......... gallica (Steiner, 1935) Filipjev, 1936 18. Buccal spear 1/20 of esophageal length . . dendrophilus (Marcinorvsky, 1909 ) Filipjev, 1^36 Buccal spear 1/12 of esophageal length ortus Fuchs, 1938 Other species: D. askenasyi (Butschli, 1873) Goodey, 1951 D. brenani (Goodey, 19i45) Goodey, 1951 D. sycobius (Cotte, 1920) Filipjev, 1936 r?) D. brevi Cauda (Micol., 1925) Filipjev, 1936 Genus Psilenchus de Han, 1921 (Key to species laodified Iroia Thoi-ne, 19li9) 1. "Mo ovaries present 2 One ovary present .,.,,..,,,,, 5 2. Spear with small basal knobs, tail clava+e • . . clavicaudatus (Micol., 1922) Thorne, I9U9 Spear without basal knobs , 3 3. Tail terminus filiform, lip region not striated t erext remus Hagemyer & Allen, 1953 Tail terminus lulbous or clavate T , I4 U, lap region striated .».,.... striatuj Thorne, 1919 Lip region plain, not striated hilar'ulus de Han, 1921 5. Spear plain without basal knobs .,..,.., magni dens Thorne, 19h9 Spear -vath di stinct bapal knobs , , , . V ,6 6. Spear curved, knobs asymmetrical. . , , aberrans Thorne, 19 h9 Spear straight, knobs symmetrical ,.,,... .^jracilis Thorne, 19h9 67. Genus Tetylenchus lilipjev 1936 (Key to the species from Thorne, 19^9) 1. Spear without basal knobs- abulbosus Thorne, 19U9 Spear Td.th basal knobs 2 2. Female tail eight times as long as anal body diameter tenius (llicoletky, 1922) Filipjev, 1936 Female tail only four or five times as long as anal body diameter . .3 3. Spear twice as long as lip region width joctus Thorne, 19li9 Spear one and one-fourth times as long as lip region width . •••*.. productus Thorne, 19h9 68. Superfainily APHK,LMGHOIDfrA (lAichs, 1937) Thorne, 19I19 Due to the diversity and inaccGssibility to all the literature o-ii'- taining to the Aphelenchoidea, coinolet^, uD-to-date keys could not be included in this syllabus. However, a rather tentative key has been constructed to the various groups of Aphelenchs following the systematics of Chitwood, 1953, as presented to the 1-th International Conq;ress of Zoology. A section in the listing of reference deals specifically with literature pertinent to ths classification of this group at and above tme generic level. Thus, it is hoped that one may recognize at least those genera found in the soil in association with plant life. Superfaraily APHl'X^'ltlCHOIDRlA (Fuchs, 1937) Thorne, 19U9 (Tentative key to fafnilies) 1. Female uterus prolapsed ". . . ^ SPHAFRITLARTIDAE (Lubbock, 1361) Skarbilovich, I9U7 (Contains 2 or 3 genera; Sphaerularia Dufour, 1837 j Tripius, Chitwood, 1935 and questionably Scatonema , Bovien, 1932.) Female uterus not prolapsed 2 2. Male with a bursa with h pairs of ribs or oapillae APH^iLENCHIDAE Steiner, 19h9 (Contains a single p:enusj Aohelenchus Bastian, 1865) Male without a bursa. . A?HT2.^NCH0IDIDaE (Fuchs, 1937) Pararaonov, 1957 P. 68 A small bursa-like membrc^ne but without ribs and or papillae is located on the tail tio of some species of Aohelenchoides (in the subgenus Rursaohelenchns) . Family APHSLEInICHOIDIDAE ( Fuchs, 1937) Paramonov, 1957 (Tentative key to subfamilies) Posterior portion of esophagus a distinct structure containing the esophageal glands and not overlapping the intestine "... PA HAPHfiiElM CHIME T. Goodey, 1951 P. 69 Posterior portion of esophagus not a distinct glandular bulb, esophageal glands considerably overlanoing the beginning of the in- testine . ." APHELENCHOIDINAE (Fuchs, 1937) P.69 Skarbilovitch, 191*7 and PArtASITAPHELENGHINAE Ruhm, 1956 p.69 69. Subfamily PAMPHELENCHINAE T.Goodeyj 1951 (Key to genera) 1. Post-bulbar region of esophagus set off from intestine by a con^ striction. Lateral fisld without longitudinal striae. ' . . . Paraphelenchus (Micolo, 1922) Micol., 1925 P. 70 Post-bulbar region of esophagus usually not set-off from intestine by a constriction. Lateral field with 10-12 incisures ^ . Metaphelenchus Steiner, 19h3 ?.70 Subfamily APHELMCHOIDINAE (Fuchs, 1937) Skarbilovitch, 19U7 (Partial key to genera) 1. Head possessing a shallow sclerotized frontal disc (a single species, A. xenuris) Anomyctus Allen^ 19U0 Head not possessing a shallow sclerotized frontal disc Aphelenchoides Fischer, I89i; . . 2 2. Tail tip with bursa-like membrane Subgenus Bursaphelenchu s (Puchs, 1937) Ruhm, 1956 Tail tip without bursa-like membrane Subgenus Aphelenchoides s. str,, Fischer, I89h P. 71 Others : Crytaphelenchus (Fuchs, 1937) Ruhm, 1956 Tylaphelenchus Rubra, 1956 Subfamily PARASITAPHELENCHINAE Ruhm, 1956 Insect inhabiting genera: Parasitaphelenchus (Fuchs, 1937) Ruhm, 1956 Ectaphelenchus (Fuchs, 1937) Peraphelench us Wachek, 1955 Entaphelenchus Wachek, 1955 70. Gemis Paraph e leiichns (hicol.j 1922) hicolc, 1925 (Key to soecies) 1. Key to females. ..»,..« ..o .»»„..„,<, ».«... = 2 Key to males h 2. Tail without mucrons myceliophthorus J. P. Goodey, 19^8 Tail with 1 or more mncrons , 3 3. Nine incisures in lateral fields pseudoparietinus (Kicol., 1922) Micolos 1925 Six incisures in lateral fields amblyiirus Steiner, 193U U. Tail with L\ or 5 papillae posterior to anus . . amhlyi;,r\is Steiner, 193U Tail with 2 or 3 papillae posterior to anus 5 5. Tail with 2 papillae posterior to anus myceliophthorus J.B. Goodey, 1958 Tail with 3 papillae posterior to anus 6 6. Tail with mucron pseudoparietinus (Micol., 1922) Micol., 1925 Tail without a mucron . . . . arenaceus (de Man, 1921) T. Goodey, 19li3 Genus Metaphelenchus Steiner, 19U3 (Key to species) 1. Lateral field with ventral bulge in tail region rhopa locercus Steiner, 19U3 Lateral field without ventral bulge in tail region' micoletzkyi (Steiner, 19lil) Steiner, 19li3 71. Genus Aphelenchoides Fischer, I89U (Partial key to species of Subgenus Aphelenchoides, Fischer, I89U) 1. Buccal spear not split at its base, either swollen at base or with- out such basal swellings. Plant parasitic species or free living forms (a long-tailed species irakes an exception to this rule and lives in the tunnels of bark beetles) , . 2 Spear split at its base up to the posterior third. Living in association with insects caprifica (Gasparrini, I87I) Filipjev & Stekhoven, I9hl 2. Tails of both sexes not flagellate 3 Tails of both sexes with a long slender flagellum 35 3.a)Body more or less cylindrical, female tail cylindrical, cylindro- conical, finger-shaped, with or without a mucron at tail tip. ... I4. b)Female tail elongate, more or less effilate but with no typical flagellumj male tail conical, ending with an acute point 11 c) Female tail as well as male tail short conoid, distinctly tapering to terminus; terminus with or without mucron I3 U. Tail without mucron; terminus uniformly smooth 5 Tail with mucron; or terminus subhemispherical with a central "dimple" 9 5. Female tail cylindro- conoid 6 Female tail cylindrical or fingershaped 7 6. Esophageal bulb situated 3.5 X its length from anterior extremity; male tail terminus acute talonus Thorne, 1935 Esophageal bulb large, situated 2 X its length from anterior extremity; male tail terminus rounded macrobulbosa Ruhm, 1956 7. Female tail cylindrical 8 Female tail finger-shaped limberi Steiner, I936 8. Head distinctly off-set, lips prominent . . . xylophilus Steiner, 193U Head not off-set, lips not prominent solani Steiner, 1935 9. Female tail cylindrical with well developed truncate or filiform mucron subtenuis (Cobb, 1926) Steiner & Buhrer, 1932 Female tail finger-shaped; terminus sub hemispherical with a central "dimple" 10 10. Female 1.1 mm long; V = 66^ abyssinicus (Filipjev, 1931) Filipjev &. Stekhoven, 19lil Female 0.7 mm long; V= 77% retusus (Cobb, 1927) Goodey, 1951 72. 11. Female tail slender, 8.8j male tail 5-5 anal body diametfjrs long cocophilus (Coiob, 1919) Qoodey, 1933 Female tail 5; male tail 2 anal body diaiaeters lon,^; 12 12. Female length 590 microns or more; tail terminus round hnnti Steiner, 1935 Female length less than 500 microns; tail terminus acute steineri Puhm, 1956 13. Tail simply conoid, without mucron or other structural modifications; spear with huf^e knobs; esophagus swollen imraediately behind soear knobs, then tanerinq; to the esophageal bulb . . . megadorus Allen, 19)41 Tail with mucron or other structural modifications; spesr with small or without knobs; esophagus narrow from behind spear to esophageal bulb " . T lU lU. Tail with k sucker-like or 3 leaf-like appendages at terminus . . . 15 Tail without sucker or leaf -like appendages at terminus; terminus provided with a mucron 16 15. Tail with U sucker-like terminal anpendages penardi (Steiner, 191i;) McBeth, 1937 Tail with 3 leaf-like terminal aopendages sphaerocephalus Goodey, 1953 16. Head with internal framework 17 Head without distinct framework 22 17. Minute species, less than 320 microns long pusillus (Thorne, 1939) Filipjev 35. -Feniale tail I'^n^th at l':ast twicR as lon,r; as vrlva-anal distarico. . 36 Fer.ale tail len:^th not ovei- 1 and ^ times as lorif^ as vulva-anal 36. Length of female, 0.8 mm; head distinctly set off from body ..... ..... . lon^icaudatus (Cohb, 1893) Ooodev, 1933 Leng'th of female, 0.5 vm; head not distinctly set off from, body o o ..... , citri Andrassy, 1957 e o e e 37. Stylet with small but distinct basal swellings or knobs » 38 Stylet without basal swellings or knobs ... ..... ...... UO 38. Postvulvar uterine sac well developed often extending nearly one-third distance from vulva to anusj male unknown . . oahuensis Christie, 1939 Postvulvar uterine sac, if present, very short; both sexes usually encountered .39 39. Vagina with stout walls and presumably moderately large and consoic- uous; excretory pore a short distance behind bulb biit in front of nerve ring; c, in female, usually 5.3 to 6.5; posterior half of male set off ......... demani (Goodey, 1928) Goodey, 1933 Vagina sm.all and inconsoicuous; excretory pore opposite or slightly behind nerve ring; c, in female, 6.7 to 8.5; oosterior half of m.ale tail only faintly set off ...<,,,,„.. oliveirae Christie, 1939 UO. Body of female with conspicuous and moderately coarse transverse striae forming distinct annules; male unknown . . linf ordi Christie, 1939 Body of female with inconspicuous transverse striae ........ I4.I III, Postvulvar uterine sac absent or very short; male tail vjith one pair of indistinct adanal and one pair of postanal oapillae ......... winchesi (Goodey, 1927) Goodey, 1933 Postvulvar uterine sac well developed usually extending at least half way from vulva to anus )42 U2. Stylet short, about lOu long; vulva relatively far anteriad, at about 62,1i; tail exceotionally long and slender, c, in fenale, about Li.5} male tail with one pair of oreanal, one pair of adanal and two pairs of postanal oapillae , . . elmiraensis van der Linde, 1938 Stylet lUu long or longer; vulva at 66^ or more; c, in fem.ale, 7 or more ..............[|3 U3' Lips faintly developed; tail of female relatively short, c, about 12; male \anknown. ............ . osvjegoensis van der Linde, 1938 Lips well developed; tail of female slender and attenuated, c, 7 ..7 to 11; male with one pair preanal, one pair indistinct and two pairs of postanal papillae ..... . tenuicaudatus (de Man, 1895) Goodey, 1933 A. conurus Steiner, 1932 k' "'s^^-i"-^^ ^^hir'^ ^^""^ A cyrtus Paesler, 1957 k' minimus Heyl, 19=^3 a! elon-atus Stekhoven, 1951 (Juv.) L' mucronatus Paesler, 19h6 A. ferrandi ni Keyl, 195U i* ^P^""^^^^ Paesler, 1957 A. hainaneniis (kahm, 1933) Goodey, 1951 I' ^taimeri Korner, IQ^i A. Ti^T^^FhilTIF Komer, 195U ^- ^a-etao Steiner, I9I4I A. mali (Puchs, 1931) Goodey, 1951 IS. Class ADEMOPHOR^^A (v.Linytovx, 1905) Chitwood, l^b'B (Key to the orders modified from Chitwood, 19?0) 1. Amphids spiral, circular, vesiculate, or other forms derivable from spiral; subventral esophageal glands never openinfi near anterior end of esophagus; caudal glands nearly always present "" CHRCKACOPTDA Chitwood, 1933 ^•'''6 Amphids pocket-like, elongated, tuboid or pore-like; subventral esophageal glands opening in anterior end of esophagus posterior to nerve ring, caudal glands present or absent 2 2. Setae on head usually present (absent in Mononchidae, Alaim.idae, and a few scattered genera of other families); typical stylet absent; esophageal gland orifices comjronly in stomatal region, glands iininu- cleate; muscular caudal sucker absent; caudal glands usually present; ventral excretory cell usually present ENOPLIDA Chitwood 1933 P.lOl Setae absent; stylet present or absent; esophageal gland orifices at anterior end of esophagus or posterior to nerve ring; muscular caudal sucker present or absent; caudal glands absent; excretory system absent or poorly developed DORYLAXKIDA Pearse, 19U2 P.1?0 76. Order CHROnADORIDA Chitwood, 1933 (Key to the suborders from Chit. & Chit., 19^0) Esooha;:;o-intestinal valve dorsoventraily flattened or circular, moderately lari-^e to very large, never triradiate or vertically flattened; stoma if well developed, unarmed or containing 1 or 3 small teeth or 6 outwardly acting teeth; stoma may or may not be surrounded by esophageal tissue; ovaries outstretched or refloxed; papilloid or tuboid supplementary organs present or absent MONHYSTERINA (Filipjev, 1929) Chit. & Chit., 1937 P. 76 Esophago-intestinal valve triradiate or vertically flattened, usually very short; stoma if well developed containing a large dorsal tooth, 3 jaws or 6 inwardly acting teeth; stoma surrounded by esophageal tissue; ovaries reflexed; cup-like or tuboid supplementary orgrns pre- sent or absent. . . . CHRCMADORINA (Filipjev, 1929) Chit. & Chit., 1937 P. 76 Suborder MONHYSTERINA (Filipjev, 1929) Chit. & Chit., 1937 (Key to the superfamilies from Chit. & Chit., 19^0) 1. Amphids circular; ends of esophageal radii convergent; ovaries out- stretched MONHYSTEROIDFA Stek. & de Coninck, 1933 P. 77 Amphids "plectoid','' spiral or variants; ends of esophageal radii tuboid 2 2. Amphids plectoid or 1-2 spiral; ovaries reflexed PLECTOIDEA Chitwood, 1937 P. 82 Amphids spiral or variants; ovaries outstretched (rarely reflexed). AXONOLAIMOIDFJl Chitwood, 1937 P. 86 Suborder CIiROM/'J)ORINA,( Filipjev, 1929) Chit. & Chit., 1937 (Key to zne superfamilies modified from Chitwood, 19^1) 1. Cuticle coarsely annulated or, if without distinct annules, covered by "hairy coat" (Marine except for one species) DFSMOSCOLECOIDEA Stekhoven, 193? P-90 Cuticle annulated 2 2. Cuticle usually punctate, stilt setae and glandular paired setae ab- sent; helmet absent. (Marine & fresh water.) CHRO'lADOROIDEA Stek. & Coninck, 1933 P. 90 Cuticle not punctate, glandular tube setae present or absent; helmet usually present. (Practically all marine) DESfiODOROIDEA Steiner, 1927 P. 97 77. Superfamily MONHYSTEfiOTDSA Chit. & Chit.^ 1937 (Key to families from Chitwood, 19^1) 1. Stoma styletifom .,.,., SIP0N0LAE4IDAE Chitv;ood, 1937 P. 77 Stoma not styletiform 2 2. Radial muscles of esophagus diffuse without cuticular attachment points MONHYSTERIDAE Oerley, 1880 P. 77 Radial muscles of esophagus in .six bands with cuticular attachment points often present , . . . .LIMO^'OEIDAE Filipjev, 1929 P. 7 7 Family SIPHONOLABilDAE Chitwood, 1937 (Key to genera after Wieser, 1956) 1. Spear present .,.,..... . Siphonolaimus de Man, 1393 Spear absent 2 2. Pharyngeal portion of esophagus attenuated, esophagus very short (b= more than 50), isthmus extremely narrow . Solenolaimus Cobb, 1893 Pharyngeal portion of esophagus not attenuated; the latter of normal length (b= about 10), isthmus not much narrower than corpus, or, if so, bulb broken down and esophageal glands free 3 3. Bulbar region of esophagus well developed . . Southernia Allgen, 1929 Bulbar region of esophagus broken down, esophageal glands free Cyartonema Cobb, 1920 Family MONHYSTERIDAE Oerley, 1880 (Key to subfamilies from Chitwood, 1951) Stoma non-sclerotized, usually conoid into esophagus. Lips three, low, cuticle not ridged; internal circle of sensory organs papilloid. (Freshwater or marine) MONHYSTERINAE Micoletzky, 1922 P. 78 Stoma sometimes sclerotized. Lips 3 or 6; cuticle striated XIALINAE Chitwood, 1951 P. 79 Family LINHOMOEIDAE Filipjev, 1929 (Key to subfamilies from Chitwood, 1951) Stoma small; esopha^o-intestinal valve elongate , LINHOMOEINAE Filipjev, 1929 P. 80 Stoma massive, globoid; esophago-intestinal valve short * ... SPHAEROLAIMINAE Filipjev, 1929 P-81 7R. Subfamily MOKHYSTEKINA'? (Key to the genera modified from Wieser, 1956) 1. Six large, se rented cephalic setae present 2 Ten cephalic setae or more present; if seemingly only six, then papillose or indistinct, not segnented 3 2. Female with one posterior reflexed ovary .... Rhabdoeoma Cobb, 1920 Female with two out-stretched ovaries Cytolainiiijin Cobb, 1920 3. Amphid an open spiral Spiramphinema Wieser, 19^6 Amphid circular or cryptospiral U U. Stoma armed with three teeth or denticles 5 Stoma imarmed 6 5. Stoma armed with three teeth Cobbia de Man, 1907 Stoma armed with three denticles Monhystrella Cobb, 1918 6. Amphids vesicular, convex, thin-walled (hence sometimes indistinct). 7 Amphids not vesicular, concave, thick-walled (always distinct). . . 9 7. Amphids circular; labial setae very long. . Proironhystera Wieser, 1956 Amphids circular to transversely elliptical or irregular to longitudinally elliptical; labial setae not elongate 8 8. Amphids circular to transversely elliptical; gubemaculum tubular Paranionhystera Steiner, 1916 Amphids irregular to longitudinally elliptical, especially large; gubemaculum absent Amphimonhystera Allgen, 1929 9. Stoma tubular, very deep Rhynchonema Cobb, 1920 Stoma cup-shaped, shallow 10 10. Cuticle striated .11 Cuticle smooth 13 11. Eight groups of subcephalic setae articulate on the same level as the cephalic setae, giving the impression of 8-radiate symmetry of the latter Steineria Micoletzky, 1921 If 8 groups of subcephalic setae present, then always articulating at a considerable distance behind the cephalic setae; the 6- radiate symmetry of the latter always obvious .... 12 12. Esophagus differentiated in posterior portion . Austronema Cobb, 1911| E3ophagus undifferentiated throughout .... Theristus Bastian, 1865 13. Stoma simple. . . . ^ Monhystera Bastian, 1865 Stoma consisting of two small cavities in tandem 11+ 79. 1\. Spicula long; no accessory piece. « . , . , Dini olaime Lla Allgfen, 1 S'2'9 Spicula short J accessory piece present .Gamiiarinema Kinne -''■ flerlach, 1953 Others: Monhystrium Cobb, 1920 - resembling Konhystera and is coramensal in frills of the land crab. Subfamily XYALINAE Chitwood, 1951 (Key to genera after Wieser, 1956) 1. Stoma armed 2 Stoma unarmed 3 2. Stoma armed with 2 plate-like teeth Gonionchxis Cobb, 1920 Stoma armed with 3 outwardly acting mandibles . . Scaptrella Cobb, 1917 3. Cuticle with 12 longitudinal wings Xenolaimus Cobb, 1>2G Cuticle with numerous longitudinal ridges, sometimes indistinct. . .I4. U. Stoma cylindrical, very large, walls strongly cuticularized Qnicronema Cobb, 1920 Stoma conical or cylindro-conical, walls less cuticularized 5 5. Long cervical and somatic setae present Xyala Cobb, 1920 Cuticle naked Dactylaimus Cobb, 1920 80, Subfariiy l/Ii'lHO! OhIINAK (Key to tlie -'ericra Tpodified from U'if^-sor, 19^5'-) 1. Cephalic ssbae absent K'etalair.ius Kreis, 1926 Cepnalic setae present 2 2. Cephalic setae U 3 Cephalic setae 8, in tvjo circles, h setae in each Ele utherolaimus Filipjev, 1922 Cephalic setae 10-12, in 1-2 circles 13 3. Buccal cavity absent, or, if small vestibulijin present, the latter not cuticularized, cup-shaped, small h Buccal cavity present 5 U. Ksopha:3us markedly differentiated into corpus, isthmus and bulb Par at ^rschf^llin^-'ia Kreis, 192U Esophagus not markedly differentiated . ~. ^ Terschellingia de Man, 1388 5. Buccal cavity armed with one to several teeth 6 Buccal Cavity unarmed 9 6. Buccal cavity long and narrow, regularly cylindrical Southemiella Allgen, 1932 Buccal cavity cup-shaped, irregular, never regularly cylindrical . . 7 7. Esophagus strongly dilated but no true bulb. Tail with flagellum . o ProsphaerolaJjnus Filipjev, I9I8 Esopha'7us with true bulb. Tail conical, without fla^ellvm 8 8. Buccal cavity with cutici'lar rings. Supplements slight elevations of preanal cuticle Synonema Cobb, 1920 Buccal cavity without cuticular rings. Supplements big, cup-shaped Aponchium Cobb, 1920 9. Buccal cavity conical to cup-shaped, never longer than wide. . . . ;10 Buccal cavity long and wide, cylindrical without constriction. . . .12 10. Esophageal bulb present 11 Esophageal bulb absent flhadinema Cobb, 1920 11. Buccal cavity with transverse cutictilar bands Desmolaimus de Man, 1880 Buccal cavity without transverse cuticular bands Metalinhopioeus de han, 1907 12. Amphids opposite posterior portion of buccal cavity Tubolaimua Allgen, 1929 Amphids opposite anterior portion of buccal cavity Latilaimus Allgen, 1933 13. Tail with sublateral rows of conoid appendages. . . Halinema Cobb, 1920 Tail without conoid appendages Ih 81. ll;. Buccal cavity absent, indistinct, or a very short, narrow ti:be. . . l5 Buccal cavity well developed. ..... ...... 18 15. All or some of the cephalic setae dilated distally .... 16 Cephalic setae normal .17 16. All 10 cephalic setae dilated distally. . . . Tubolaimella Allgen, 193U Only the k anterior setae dilated Linhomoella Cobb, 1920 17. 12 papillose cephalic setae; papillae on tail Anticyathus Cobb, 1920 10 long cephalic setae; no papillae on tail Sphaerocephalum Filipjev, I9I8 18. Buccal cavity cup-shaped, never longer than wide 19 Buccal cavity cylindrical, longer than wide E\imorpholaiirius Schuiz, 1932 Pandolairnus Allgen, 1929 Filipjevinema Allgen, 1953 Pulchranemella Cobb, 1932 19. Buccal cavity armed with teeth, or very thick cuticular plates Linhon'oeus Bastian, 1865 Buccal cavity unarmed, thin walled 20 20. 12 cephalic setae Peril inhomoeus Stekhoven, 1950 10 cephalic setae 21 21. "Labial palps" presence Crystallenema Cobb, 1920 "Labial palps" absent Paralinhornoeus de Man, 1907 Subfairlly SPHAEROLABilNAE (Key to genera modified from Chitwood, 1951) 1. Cephalic sensory organs papilloid or setose • 2 Cephalic sensory organs not observed. . . . Sphaerolaimus Bastian, l8o5 2. Cephalic sensory organs papilloid Tripylium Cobb, 1920 Cephalic sensory organs setose .3 3. Female with one anterior out-stretched ovary. . . Omicronema Cobb, 1920 Female with one posterior out-stretched ovary . Halanonchus Cobb, 1920 81. Suoerfamily PLnCTOIDFA Chit. & Chit., 1937 (Key to the families after Chitwood, 1951) 1. Posterior region of esophaj'^s muscular j stoma cylindrical or conoid .2 Posterior region of esophagus glandularj stoma minute or absent CMA COLA m IDA E Stekhoven & de Coninck, 1933 -^.^'2 2. Esophagus terminated by a distinct "gamma" valved biilb PLECTIDAE Oerley, 1580 P. 82 Bulbar region of esophagus with or without a "chromadoroid" valved bulb LEPTOLAIMIDAE Oerley, 1880 P. '2 Appendix to PLECTOIDEA (after Chit. & Chit., 1950) : BASTIANIIDAE Stekhoven & Teuinissen, 1938. Stoma very long and narrow, surrounded by esophageal tissue, or stoma rudimentary; esoph- agus cylindrical, greatly elongate; amphids circular to unispiral; ovaries reflexed. Contains one genus, Bastiania de Man, 1876. Family CAFlACOLAIMIDAE Stekhoven & de Coninck, 1933 (Key to the subfamilies after Chitwood, 1951) Amphids anterior to cephalic setae (Marine) CA>ULCOLAIMINAE Micoletzky, 192U P. 83 Amphids posterior to cephalic setae (Marine or fresh water) APHANOLAMINAE Chitwood, 1935 P-83 Family PLECTIDAE Oerley, lu80 (Key to the sulafamilies after Chitwood, 1951) Labial region with web-like or other modifications WILSONMATINAE Chitwood, 1951 P-^U Labial region without specialized modifications PLT5CTINAE Micoletzky, 1922 P.8U Family LEPTOLAIMIDAE Oerley, 1880 (Key to the subfamilies after Chitwood, 1951 & 1956) 1. Amphids large, circular to unispiral 2 Amphids minute, pore-like RHABDOLAIXINAE Chitwood, 1951 ^'85 2. Esophagus with non- valved bulb LEPTOLAIMINAR Chitwood, 1951 Esophagus with a "chromadoroid" valved bulb HALIPLECTINAE Chitwood, 1951 P-55 03. Subfamily CAl^lACOLAIMINA^ Stekhoven & de Coninck, 1933 (Key to genera after Wieser, 1956) J- • UC6XXX aOS^iiv ••»*oe«e««ee9««»eea««aee99ae C. Ocelli present 5 2. Stylet-like tooth absent Neurella Cobb, 1920 Stylet-like tooth present 3 3. I'Jhole tooth embedded in esophageal tissue . . Caraacolaimus de Man, 1889 Distal portion of tooth free in vestibulum I4. U. Tooth blunt Aconthiolaiirius Filipjev, I9I8 "Tooth" needle-shaped . . Camacolainioides de Coninck & Stekhoven, 1933 5. Stylet-like tooth absent Jonema Cobb, 1920 Stylet-like tooth present Nemella Cobb, 1920 Subfamily APHANOLAffilNAR Chitwood, 1935 (Key to genera) 1. Ovaries paired 2 Ovary single Alaimella Cobb, 1920 2. Stoma practically invisible Aphanolaimus de Man, 1880 Stoma short and broad, prismatic or cylindrical Paraphanolairrus Kicol, 1923 8U. Subfamily WILSONBIATINAE Chitwood, 1951 (Key to the genera from Cobb, 1935) 1. Terminal bulb valved 2 Terminal bulb not valved Anonchus Cobb, 1913 2. Lips 6, distinct, revolute; striae fine; amphids semicircular Anthonema Cobb, I906 Lips not revolute; head with dorso-ventral bladders; striae coarse; amphids roimd 3 3. Cephalic appendages elaborately palmate Wilsonema Cobb, 1913 Cephalic appendages forming a closed, striated dome or cupola Bitholinema de Coninck, 1931 Subfamily PLECTINAE Micoletzky, 1922 (Key to the genera) 1. Esopha;^s short, cardia extremely long. . . Paranlectonema Strand, 1936 Esophagus not usually short, cardia moderate 2 2. Stoma very short conoid; esophagus very long. . Chronogaster Cobb, 1913 P.&h Stoma not very short, esophagus not unusually long 3 3. Male with conoid supplementary organs Anaplectus de Coninck & Stekhoven, 1933 Male with papilloid supplementary organs Plectus Bastian, 1865 Genus Chronogaster Cobb, 1913 (Key to the species modified from Andrassy, 1958) 1. Longitudinal striations present . . 2 Longitudinal striations absent 3 2. Tail terminus with 3 small appendages . . . magnificus Andrassy, 1956 Tail terminus without appendages alatum Gerlach, 195U 3. Tail terminus with h appendages longicollis (Daday, 1899) Andrassy, 1958 Tail terminus with only 1 appendage U I4. Body extremely thin (a^almost 100); mouth cavity symmetrically constricted, funnel-shaped subtilis Andrassy, 1958 Body not as thin (asbelow 70); mouth cavity prismatoid 5 5. Body cavity with numerous distinct crystals; lateral glands large, striking typicus (de Man, 1921) de Coninck, 1935 Body cavity without crystals; lateral glands indistinct 6 6, Amphid situated posterior to the mouth cavity, soiral; tail shorter than 1/10 the body length boettgeri Kischke, 1956 Amphid situated at the level of the mouth cavity, buckle-shaped; tail very long 85. S-nbfainily hM^BIX'TAIMINA^ Hhitwoo.d, ly.^^l (Key to the genera) 1. Stoma with 3 minute outwardly acting teeth. Syrin,';olaiin\i5 de Man, 1883 Stoma without teeth ...» Phabdolaimus de Man, 1880 Subfamily HALIPLEGTINAE Chitwood, 1951 (Key to the genera modified from Cobb, 1935) 1. Latei*al alae present ... Aplectus Cobb, 191il Lateral alae absent 2 2. Median bulb present Haliplectus Cobb, 1913 P. ^35 Median bulb absent 3 3. Head constricted at cephalic setae Polylaimium Cobb, 1920 Head not constricted at cephalic setae . Linolaimus Cobb, 1933 Genus Haliplectus Cobb, 1913 (Key to species from Chitwood, 1956) 1. Amphids slightly more than 1 head diameter back from anterior extremity 2 Amphids distinctly more than 1 head diameter back from anterior extremity 3 2. Only female known, 1.9 mm. long (amphids 2/5 as wide as head, inter- rupt 5 annules conicephalum Cobb, in Chitwood, 1956 Only male known, 1.0 mm long .... dorsalis Cobb, in Chitwood, 1956 # 3. Male with 6 preanal supplements .floridensis Cobb, in Chitvrood, 1956 Male with no preanal supplements. pellucidus Cobb, 1913 Male with h preanal supplements , ^ , bickneri Chitwood, 1956 <'i6. Superfamily AXOwOLAIKOIDEA Chit, and Chit., 1937 (Key to the families after Chitwood, 1951) Amphids unispiral, spiral to shephard's crook, rarely broken circle; cuticle not punctate or minutely pijnctate, usually rather smooth; gubemaculum usually with posterior apophyses AXONOLAE-IDAR Stekhoven & de Coninck, 1933 ?."6 Amphids multispiral; cuticle often having minute to moderately coarse punctations. Stoma cylindroid with three sclerotized points at an- terior end or reduced; gubemaculum with or without a posterior apo- physis CCMESCMATIDAE (Stekhoven