On the Plant-Parasitic Nematode Genera Merlinius Gen. N. and Tylenchorhynchus Cobb and the Classification of the Families Dolichodoridae and Belonolaimidae N

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can species of Gyrodactylus, Am. Midi. Nat. Price, E. W. 1938. The monogenetic trema- 79: 205-215. todes of Latin America. In Livro Jubilar Mizelle, J. D., and D. C. Kritsky. 1967a. Prof. Travassos, Rio de Janeiro, Brazil. 3: Studies on monogenetic trematodes. XXX. 407-413. Five new species of Gyrodactylus from the Rogers, W. A. 1968. Eight new species of Pacific tomcod, Microgadus proximus (Gi- Gyrodactylus (Monogenea) from the South- rard). J. Parasit. 53: 263-269. eastern U.S. with redescriptions of G. fair- , and . 1967b. Studies on mono- porti Van Cleave, 1921, and G. cyprini genetic trematodes. XXXIII. New species of Diarova, 1964. J. Parasit. 54: 490-495, Gyrodactylus and a key to the North Ameri- , and T. L. Wellborn. 1965. Studies can species. Tr. Am. Micr. Soc. 86: 390-401. on Gyrodactylus (Trematoda: Monogenea) Price, C. E., and W. A. Bussing. 1967. Mono- with descriptions of five new species from genean parasites of Costa Rican fishes. Part Southeastern U.S. J. Parasit. 51: 977-982. 1. Descriptions of two new species of Cleido- Turnbull, E. R. 1956. Gyrodactylus bullata- discus Mueller, 1934. Riv. Parassit. 28: 81- nidis n. sp. from Leblstes reticulatus Peters 86. with a study of its life cycle. Can. ]. Zool. , and . 1968. Monogenean para- 34: 583-594. sites of Costa Rican fishes. II. Proposal of Yamaguti, S. 1963. Systema helminthum. IV. Palombitrema heteroanci&trium n. gen., n. sp. Monogenea and Aspidocotylea. Interscience Proc. Helm. Soc. Wash. 35: 54-57. Publishers, Inc., New York.

On the Plant-parasitic Nematode Genera Merlinius gen. n. and Tylenchorhynchus Cobb and the Classification of the Families Dolichodoridae and Belonolaimidae n. rank

MOHAMMAD RAFIQ SIDDIQI Commonwealth Bureau of Helminthology, St. Albans, Hertfordshire, England

ABSTRACT: Merlinius gen. n. is proposed for 32 species of Tylenchorhynchus, sensu lato, which have six incisures in the lateral fields, rather cylindroicl spicules with prominently notched distal end, a nonprotruding gubernaculum and a moderately developed bursa. Tylenchorhynchus Cobb is redefined and T. iiliginosus sp. n. and T. papyrus sp. n. are described from swampy areas in Uganda. The diagnoses, composition and relationships of Dolichodoridae and Belonolaimidae n. rank are detailed. Tetylenchus Filipjev is placed in a new subfamily Tetylenchinae under Tylenchiclae.

In his review of the genus Tylenchorhynchus Allen) and T. dubhis (Biitschli) from Holland, Cobb, 1913, Allen (1955) pointed out the Belgium and England which was regarded as existing diversity in the morphological char- type by Filipjev (1934) for his new subgenus acters exhibited by various species and prophe- Bitylenchus, later (1936) synonymized by him sied the creation of new genera within this with Tylenchorhynchus. group; two related genera, Nagelus and Geo- This study shows that whereas T. dubins cenamus, have since been proposed by Thorne and T. cylindricus are congeneric, a number of and Malek (1968). Tarjan (1964) and de other species show considerable differences in Ouiran (1967) gave differential keys for 68 their morphology which are considered of ge- and 71 valid species of Tylenchorhynchus re- neric status. Consequently, Merlinius gen. n. is spectively and 25 more new species have since here proposed for those species of Tylenchor- been described. I had the opportunity of hynchus, sensu lato, which have six incisures studying the specimens of over fifty valid in the lateral fields, deirids frequently present, species in this genus including the type species, a small trough-shaped nonprotrusible guber- T. cylindrical Cobb (made available by Dr. naculum and characteristic spicules which

Copyright © 2011, The Helminthological Society of Washington OF WASHINGTON, VOLUME 37, NUMBER 1, JANUARY 1970 69 markedly differ from those of Tylenchorhyn- M. dubius (Steiner, 1914) comb. n. chus. Both the genera are described below. syn. Aphelenchus dubius Steiner, 1914 Anguillulina macrura Goodey, 1932 Merlinius} gen. n. Tylenchorhynchus macrurus (Goodey, DIAGNOSIS: Tylenchorhynchinae: Dolicho- 1932) Filipjev, 1936 doridae. Lateral fields with six incisures. ? T. graminicola Kirjanova, 1951 Deirids frequently present. Lip region sym- M. galeatus (Litvinova, 1946) comb. n. metrical, with four or more annules but without syn. T. galeatus Litvinova, 1946 a perioral disc. Amphids prominent pores or M. grandis (Allen, 1955) comb. n. oblique slits close to oral opening. Labial syn. T. grandis Allen, 1955 framework lightly to heavily sclerotized. A M. hexagrammus (Sturhan, 1966) comb. n. single papilla on outer margins of each sub- syn. T. hexagrammus Sturhan, 1966 median lip. Protrudor muscles of spear at- M. hexincisus (Jairajpuri and Baqri, 1968) tached to the base of labial framework. Basal comb. n. bulb large, with well developed carclia. Vulva syn. T. hexincisus Jairajpuri and Baqri, usually with double epiptygma and lateral 1968 membranes; cloaca with two pedunculate pa- M. icarus (Wallace and Greet, 1984) comb. n. pilla-like protuberances ventro-laterally, here syn. T. icarus Wallace and Greet, 1984 named as hypoptygma. Ovaries symmetrical. M. laminatus (Wu, 1969) comb. n. Female tail cylindroid to subcylindroid; male syn. T. laminatus Wu, 1969 tail enveloped by a moderately developed M. lenorus (Brown, 1956) comb. n. bursa. Spicules stout, rather cylindroid; distal syn. T. lenorus Brown, 1956 end broadly rounded, notched and devoid of M. leptus (Allen, 1955) comb. n. large ventral flanges. Gubernaculum small, syn. T. leptus Allen, 1955 trough-shaped in lateral view, not protrusible. M. lineatus (Allen, 1955) comb. n. syn. T. lineatus Allen, 1955 Type species M. macrodens (Allen, 1955) comb. n. Merlinius brevidens (Allen, 1955) comb. n. syn. T. macrodens Allen, 1955 syn. Tylenchorhynchus brevidens Allen, 1955 M. microdorus (Geraert, 1966) comb. n. syn. T. microdorus Geraert, 1966 Other species M. nothus (Allen, 1955) comb. n. syn. T. nothus Allen, 1955 Merlinius affinis (Allen, 1955) comb. n. M. obscurisulcatus (Andrassy, 1959) comb. n. syn. Tylenchorhynchus affinis Allen, 1955 syn. T. obscurisulcatus Andrassy, 1959 M. alpinus (Allen, 1955) comb. n. M. obscurus (Allen, 1955) comb. n. syn. T. alpinus Allen, 1955 syn. T. obscurus Allen, 1955 M. bavaricus (Sturhan, 1966) comb. n. M. quadrifer (Andrassy, 1954) comb. n. syn. T. bavaricus Sturhan, 1966 syn. T. quadrifer Andrassy, 1954 M. berberides (Sethi and Swarup, 1968) comb. T. ornatus Allen, 1955 n. M. rugosus (Siddiqi, 1962) comb. n. syn. T. berberides Sethi and Swarup, 1968 syn. T. rugosus Siddiqi, 1962 M. bogdanovikatjkovi (Kirjanova, 1941) comb. M. socialis (Andrassy, 1962) comb. n. n. syn. T. socialis Andrassy, 1962 syn. T. bogdanovikatjkovi (Kirjanova, 1941) M. stegus (Thorne and Malek, 1968) comb. n. Loof, 1959 syn. T. stegus Thorne and Malek, 1968 Anguillulina bogdanovikatjkovi Kirjanova, M. supsrbus (Allen, 1955) comb. n. 1941 syn. T. superbus Allen, 1955 M. conicus (Allen, 1955) comb. n. M. tartuensis (Krall, 1959) comb. n. syn. T. conicus Allen, 1955 syn. T. tartuensis Krall, 1959 M. cylindricaudatus (Ivanova, 1968) comb. n. M. tessellatus (Goodey, 1952) comb. n. syn. T. cylindricaudatus Ivanova, 1968 syn. T. tessellatus Goodey, 1952 M. undyferrus (Haque, 1987) comb. n. 1 Named in honor of Dr. Merlin W. Allen, University of California, U. S. A. syn. T. undyferrus Haque, 1967

Figure 1. A—I. Tylenchorhynchus, J—V. Merlinius. A and B. T. cylindricus. C and D. T. capitatus. E-G. T. dubius. H and I. T. nudus from blue grass, Wisconsin, U.S.A. J-P. M. icarus from grasses, St. Albans, England. O. M. alpinus, paratype. R. M. nanus from Belgium. S. M. microdorus from onion soil, Rampur City, India. T. M. grandis, paratype. U and V. M. quadrijer from Belgium. C, E and J. En face of female. K. Transverse section through basal plate. A and P. Head end of female. S. Head end of male. L, M and V. Vulval region showing epiptygma. B, D, F, I, N, O, R, T and U. Spicular regions. J. Part of female esophagus showing deirid in lateral field.

M. varians (Thome and Malek, 1968) comb. n. portion pointed and prominently flanged ven- syn. T. varians Thorne and Malek, 1968 trally. Gubernaculum large, rod-like in lateral Tylenchorhynchus brachycephalus Litvinova, view, sometimes with proximal portion dor- 1946 is a problematical species. The female sally bent, capable of protruding through anus. measuring 0.70-0.77 mm long has head-end Bursa terminal, well developed. and tail-end like those of Helicotylenchus TYPE SPECIES: Tylenchorhynchus cylindricus whereas the male measuring 0.93-1.20 mm is Cobb, 1913. apparently a Merlinius. However the female Two new species of this genus, T. uliginosus is reported to have six incisures in the lateral and T. papyrus, collected from swampy areas field which is contrary to the definition of in Uganda are described below. These come Helicotylenchus. close to T. rhopalocercus Seinhorst, 1963, RELATIONSHIP: Merlinius differs from Tylen- which was transferred by Seinhorst (1968) to chorhynchus in having six incisures in the the genus Trichotylenchus Whitehead, 1959. I lateral field, usual presence of deirids, the males have collected specimens of T. rhopalocercus having characteristic spicules lacking large from sugarcane soil samples originating in ventral flanges and small, nonprotruding guber- Jebba, Nigeria and these fit well the original naculum. description. The species has a definite basal Nagelus Thorne and Malek, 1968 lacks a esophageal bulb and is, therefore, retained in labial framework, has asymmetrical lip region, Tylenchorhynchus. angular spear knobs and protractor muscles of the spear attached to the cuticularized inner Tylenchorhynchus uliginosus sp. n. walls of the labial cavity. (Fig. 2, A-I) Geocenamus Thorne and Malek, 1968 is Measurements characterized by having a refractive labial disc from which a slender spear guide extends back FEMALES (25): L = 0.40-0.64 mm; a = almost one-third length of the exceedingly 30-37; b = 4.4-5.6; c = 10.5-13.0; V = slender spear. According to Thorne and Malek 52-58; spear = 14-16 p. (1968) the head and spear of Geocenamus are FEMALE (HOLOTYPE): L = 0.6 mm; a = reminiscent of those of Dolichodorus rather 34; b = 4.8; c = 12; V = 26-54-25; spear than Tylenchorhynchus. = 15.5 p. I have seen deirids in the following species: MALES (10): L = 0.48-0.54 mm; a = Merlinius affinis, M. alpinus, M. brevidens, M. 31-37; b = 4.4-5.5; c = 12-14; T = 55-62; conicus, M. dubius, M. grandis, M. icarus, M. spear = 14-15 p,; spicules (measured along microdorus and M. nanus. Figure 1 (J—V) dorsal line) = 19—21 //.; gubernaculum = 9.5— gives further information on certain species of 10.5 fj,. this genus. Description Genus Tylenchorhynchus Cobb, 1913 FEMALE: Body in an open "C" form when syn. Bitylenchus Filipjev, 1934 relaxed by gentle heat; transverse striae rather DIAGNOSIS (emended): Tylenchorhynchinae : coarse, 1.25 ^ apart near middle. Lateral fields Dolichodoridae. Lip region symmetrical, offset aerolated, about one-fourth body width; three or continuous with body; labial framework incisures; outer ones crenate. Phasmids distinct, lightly to heavily sclerotized; labial disc absent. variable in position from a little anterior to Lateral fields with 3-5 incisures. Deirids slightly posterior to middle of tail. Lip region rarely present. Spear usually well developed conoid-rounded, with 6-7 annules; framework with prominent basal knobs and anteriorly lightly sclerotized, with outer margins extend- tapering portion appearing nontubular and ing 2—3 body annules from basal plate. En needle-like distally; protractor muscles attached face of female head shows six papillae in inner to the base of the labial framework. Median and eight in outer circlet of which four nearer and basal bulbs of esophagus well developed. to amphids are most prominent and large, and Convoluted tubules running along entire in- circular openings of the amphids (Fig. 2, B). testinal region present in many species. Spic- Three-fourths of anterior part of spear needle- ules cephalated, ventrally arcuate, with distal like, not tubular; orifice of dorsal esophageal

15 A-D,G-I

25 .. E, F

, 5$&ail \ \e 2, A-I. Tylenchorhynchus uliginosus n. sp. A, B and D-H. Female. C and I. Male. A and C.

Head ends. B. En face view. D. Vulval region. E. Part of anterior reproductive branch. F. Esophageal region. G—I. Tail ends.

Copyright © 2011, The Helminthological Society of Washington OF WASHINGTON, VOLUME 37, NUMBER 1, JANUARY 1970 73 gland 2 p. behind spear base. Esophagus typi- FEMALE (HOLOTYPE): L = 0.93 mm; a = cal (Fig. 2, F), cardia apparently made up of 40; b = 6.6; c = 14.3; V = 28-52-:M); spear two large cells. Excretory pore near anterior — Zo.DO oC p.. end of basal esophageal bulb. Hemizonid two MALES (4): L = 0.69-0.75 mm; a = 35- body annules long, just anterior to excretory 40; b = 5.1-5.7; c = 14-15; T = 55-65. pore. Vulva with double epiptygma; vagina extending half-way across body (Fig. 2, D); Description spermatheca packed with round sperms 2 ^ in FEMALE: Body ventrally arcuate, transverse diameter; ovaries with 1—2 rows of oocytes. striae 1.2—1.8 p, apart near mid-body. Lateral Tail elongate-clavate, 4.6—5.0 X anal body- fields with three incisures. Lip region conoid- width long; tail terminus with thick cuticle, rounded, with 7—8 annules; framework lightly coarsely striated. sclerotized. Spear very thin 23-24 ^ long, MALE: Essentially similar to female. Bursa with minute, backwardly directed basal large, finely crenate arising at about V/2 knobs, its anterior part longer than the pos- spicular lengths in front of anus. Phasmids terior. Dorsal esophageal gland opening 2.5- near middle of tail. Lateral field, spicule and 3.0 p, behind base of spear. Hemizonid three gubemaculum as shown in Figure 2, I. body annules long, a little behind nerve ring. RELATIONSHIP: This species is close to T. Excretory pore in the region of the hemizonid rhopalocerciis Seinhorst, 1963, T. bifasciatiis or just behind. Basal esophageal bulb rather Andrassy, 1961 and T. palustris Merny and elongate, its base applied to anterior face of Germani, 1968. T. rhopalocerciis has females intestine. Cardia large, rounded to slightly with 0.62-0.81 mm long body, spear measuring discoiclal. Large spherical granules present in 17-19 p, long and tail almost six anal body- the intestinal cells. A post-intestinal sac absent widths long. T. bifasciatiis has 0.65-0.73 mm but coiled tubules possibly associated with ex- long body, 19-20 // long spear and female tail cretory system extend into tail cavity a little only 2.6-2.7 anal body-widths long. T. palus- behind anal region. Tail elongate-subclavate tris has fewer labial annules and female tail with striated terminus, 3.7-4.2 times anal measuring 2.7-3.9 anal body-widths long and body-width long; phasmids at middle of tail or having unstriated terminus. further anterior (Fig. 3, E). Vulva depressed. TYPE HABITAT AND LOCALITY: Collected by Spermatheca irregularly rounded. Ovaries with Prof. W. B. Banage from swampy soil near a single row of oocytes. fish pond in Kabanyolo, near Kampala, MALE: General characters as for female. Uganda. Spear averaging 23.5 p. long. Spicules 26—29 p. TYPE MATERIAL: Holotype female, four long as measured along their dorsal side, with paratype females and two paratype males at large ventral flanges; gubemaculum 13 p. long, Nematology Department, Rothamsted Experi- with a large dorsal spine at proximal end; mental Station, Harpenden, England; two lateral fields aerolated, disappear before the paratype females and two paratype males at phasmids; bursa distinctly crenate (Fig. 3, C). each of the following centers: Nematology De- Phasmids prominent, anterior to middle of tail. partment, University of California, Davis, Cali- RELATIONSHIP: T. papyrus sp. n. differs fornia, USA; Nematology Department, Land- from T. bifasciatiis in having a longer spear, a bouwhogeschool, Wageningen, The Nether- subclavate female tail measuring over three lands; Department of Zoology, Aligarh Muslim anal body-widths long and in the more anterior University, Aligarh, India; the remainder at position of the phasmids (in latter species spear the Commonwealth Bureau of Helminthology, = 19-20 ^ long, tail = 2.6-2.7 times anal St. Albans, England. body-widths and phasmids in female behind the middle of the tail). T. rhopalocerciis has Tylenchorhynchus papyrus sp. n. spear 17-19 p., spicules 21 p, and gubemaculum (Fig. 3, A-F) 8 p, long and the female tail is almost six anal Measurements body-widths in length. FEMALES (5): L = 0.80-0.94 mm; a = TYPE HABITAT AND LOCALITY: Collected by 37-43; b = 5.5-6.6; c = 12.5-16.0; V = Professor W. B. Banage from soil in Papyrus 52-55. swamp, Namulonge, Uganda.

A \\

Figure 3, A-F. Tylenchorhynchus papyrus n. sp. C. Male, rest female. A. Head end. B. Esophageal region. C and E. Tail ends. D. Part of anterior reproductive branch. F. Basal Esophageal bulb and cardia.

TYPE MATERIAL: Holotype female and a in Nagelus. Spear usually well developed and pair of paratypes (1 $, 1 9 ) at Nematology over 15 ^ in length, with prominent basal Department, Rothamsted Experimental Station, knobs; its protractor muscles almost parallel to Harpenden, Hertfordshire, England; a pair body axis. Amphids labial; deirids sometimes of paratypes (1 $, 1 2 ) at Nematology De- present; phasmids pore-like, near middle of tail. partment, University of California, Davis, Median esophageal bulb strongly muscular. California, USA and the remainder at Com- Esophageal glands enclosed in and forming monwealth Bureau of Helminthology, St. basal esophageal bulb. A cellular cardia pres- Albans, England. ent, projecting into lumen of intestine. Ovaries The systematic position of Tylenchorhyn- usually paired; spermatheca a small pouch; chinae Eliava, 1964 is not clear at the moment. sperms small, rounded, with little cytoplasm. Allen and Sher (1967) assigned this subfamily Bursa completely enveloping tail except in along with Dolichodorinae, Telotylenchinae, Tylodorinae, with phasmid extending as a Belonolaiminae, Hoplolaiminae, Pratylenchinae false rib. Tail in female elongate (very rarely etc., to the family Tylenchidae. Paramonov under twice anal body-width), conoid, cylindri- (1967) considered it under Hoplolaimidae cal or filiform. Ectoparasitic on roots of higher along with Hoplolaiminae, Rotylenchoidinae, plants. Belonolaiminae, Dolichodorinae and Trophuri- Dolichodoridae is related to Tylenchidae in nae. Husain and Khan (1967) defined it as a having a basal esophageal bulb enclosing the subfamily of Tylenchidae considering under it esophageal glands but is differentiated by its the genus Telotylenchus Siddiqi, 1960. Thorne sclerotized labial framework, well developed and Malek (1968) questioned this latter action spear with tubular arrangement of the protrac- and gave an emended diagnosis of the sub- tor muscles, a strongly muscular median family to exclude Telotylenchus. esophageal bulb and large bursa which is As elaborately discussed by Paramonov usually terminal. Members of this family (1967, 1968) there are sufficient reasons, both represent a higher stage over those of Tylenchi- morphological and ecological, to support the dae in their adaptation to the parasitism of the view that the subfamilies Dolichodorinae, roots of the spermatophytes (see Paramonov, Tylenchorhynchinae, Trophurinae, Tylodorinae, 1967 and 1968). Belonolaiminae, Telotylenchinae, and Aphas- matylenchinae do not belong in the family Key to subfamilies and genera of Tylenchidae but are closer to Hoplolaimidae Dolichodoridae in being sufficiently advanced ectoparasites of 1. Tail in both sexes filiform, bursa plant roots. However, the first four of these adanal ____ Tylodorinae Paramonov, 1967; have a fundamentally different type of esopha- Tylodoms Meagher, 1964 gus than the rest, in that the esophageal glands Tail in both sexes not filiform, bursa do not lie free in the body cavity but form a terminal 2 compact basal esophageal bulb joined to the intestine through a prominent cellular cardia. 2. Bursa trilobed Dolichodorinae The former group of subfamilies is regarded Chitwood and Chitwood, 1950 3 to constitute the family Dolichodoridae (Chit- Bursa simple 4 wood and Chitwood, 1950) Skarbilovich, 1959 3. Spear abnormally long, lip region four- and the latter is here proposed to form a lobed Dolichodorus Cobb, 1914 separate family Belonolaimidae (Whiteheacl, Spear not as long, lip region smoothly 1959) n. rank. Diagnoses, composition and rounded Brachy- relationships of these two families are given dorus de Guiran and Germani, 1968 below. 4. Body cuticle abnormally thick espe- Dolichodoridae (Chitwood and Chitwood, cially on tail, indistinctly striated _ 1950) Skarbilovich, 1959 Trophurinae Paramonov, 1967 5 DIAGNOSIS (EMENDED) : Tylenchoidea. Lat- Body cuticle not abnormally thick, eral fields with six or less incisures. Labial distinctly striated framework lightly to heavily sclerotized, absent Tylenchorhynchinae Eliava, 1964 6

5. Ovaries paired, spear abnormally long Key to subfamilies and genera of Macrotrophurus Loof, 1958 Belonolaimidae Ovary single, spear not as long 1. Phasmids absent, esophageal glands Trophurus Loof, 1956 mostly on ventral side of intestine (syn. Clavaitrotylenchus Caveness, 1958) ____ Aphasmatylenchinae Sher, 1965; 6. Lateral fields with 6 incisures 7 Aphasmatylenchus Sher, 1965 Lateral fields with 3-5 incisures Phasmids present, esophageal glands Tylcnchorhynchus Cobb, 1913 mostly on dorsal and lateral sides of intestine 2 7. Protractors of spear attached to the 2. Lip region four-lobed with lateral lips cuticularized inner walls of the considerably reduced labial cavity, labial framework ab- Belonolaiminae Whitehead, 1959 3 sent .... Nagelus Thorne and Malelc, 1968 Lip region not so Protractors of spear attached to the Telotylenchinae Sicldiqi, 1960 4 base of the labial framework 8 3. Labial disc circular Belonolaimus 8. Labial disc very conspicuous Steiner, 1949 Geocenamus Thorne and Malek, 1968 Labial disc lemon-shaped due to Labial disc absent __ Merlinius gen. n. lateral extensions Morulaimus Sauer, 1966 Belonolaimidae (Whitehead, 1959) n. rank 4. Labial disc present, prominent DIAGNOSIS: Tylenchoidea. Body with promi- Carphodonis Colbran, 1965 nent transverse striae; lateral fields with four Labial disc indistinct or absent 5 incisures or less. Female tail elongate-conoid 5. Spear well developed, lateral fields or cylinclroid, very rarely under twice anal with 4 incisures body-widths in length, with phasmids located Telotylenckus Siddiqi, 1960 near middle; male tail completely enveloped Spear greatly attenuated, lateral fields by bursa. Lip region offset or continuous, not with 3 incisures low or flattened, with light to heavy sclerotiza- Trichotylenchiis Whitehead, 1959 tion. Amphids labial, a single papilla on outer margins of each submeclian lip. Spear well Thorne and Malek (1968) considered the developed, with tubular protractor muscles. genus Tetylenchit?, Filipjev, 1936 under Tylen- Median esophageal bulb strongly muscular; chorhynchinae. However, it appears to belong basal bulb absent. Esophageal glands free, to Tylenchidae because the protrudor muscles forming a long overlap over anterior end of of the spear are oblique to body axis being intestine; dorsal gland enormously enlarged, attached to the cuticular band at the base of extending past subventrals which are often the lip region (see Thorne and Malek, 1968); greatly reduced. Cardia reduced or absent. the labial-framework, spear and median Ovaries paired, opposed, outstretched. Spicules esophageal bulb are weakly developed and and gubernaculum well developed. Ectopara- the bursa is not terminal. The genus does not sitic on roots of higher plants. fit any of the existing subfamilies of Tylenchi- Belonolaimidae differs from Hoplolaimidae dae i.e. Tylenchinae, Psilenchinae Paramonov, (Filipjev, 1934) Wieser, 1953 in having the 1967 or Anguininae Paramonov, 1962, and dorsal esophageal gland prominently larger therefore a new subfamily, Tetylenchinae, is and extending well past the subventrals which proposed to receive it. are considerably reduced and the elongate tails in both, sexes with phasmids located near the Tetylenchinae subfam. n. middle. From Pratylenchiclae (Thorne, 1949) DIAGNOSIS: Tylenchidae. Deirids and phas- Sicldiqi, 1963 this family differs in having a mids usually distinct. Amphids pore-like, lip region which is neither low nor flattened, a labial, close to oral opening. Four prominent large dorsal esophageal gland extending past submeclian papillae on the outer contour of lip the subventrals and in not being endoparasites region. Spear elongate-slender, with or without of roots. basal knobs. Median esophageal bulb oval;

Copyright © 2011, The Helminthological Society of Washington OF WASHINGTON, VOLUME 37, NUMBER 1, JANUARY 1970 77 cardia usually discoidal. Vulva median; ov- de Guiran, G. 1967. Description de deux es- aries paired, outstretched. Tail in both sexes peces nouvelles du genre Tylenchorhynchus elongate-conoid, not filiform; in male en- Cobb, 1913 (Nematoda: Tylenchinae) accom- veloped by a subterminal bursa. pagnee d'une cle des femelles, et precisions sur T. mamillatus Tobar-Jimenez, 1966. Ne- TYPE AND ONLY GENUS: Tetijlenchus Filip- matologica 13: 217-230. ' jev, 1936. Husain, S. I., and A. M. Khan. 1967. A new Tetylenchinae differs from Psilenchinae in subfamily, a new subgenus and eight new having pore-like amphids which are labial in species of nematodes from India belonging position, conoid tail and large, subterminal to superfamily Tylenchoidea. Proc. Helm. bursa. From Tylenchinae it is differentiated Soc. Wash. 34: 175-186. in having conoid tail, paired ovaries and large, Paramonov, A. A. 1967. A critical review of subterminal bursa. the suborder Tylenchina (Filipjev, 1934) (Nematoda: Secernentea). In: Problems in Acknowledgments morphology, taxonomy and biology of nematodes of plants. (Russian Text). Trudy Gel'- The author wishes to thank Doctors M. W. mint. Lab. 18: 78-101. Allen, E. Geraert, P. A. A. Loof and J. W. . 1968. Principles of ecologo-morpholog- Seinhorst for providing him with specimen ical analysis of organization of Tylenchida slides of several species of Tylenchorhynchus Thorne, 1949. (Russian Text). Izv. Akad. and Merlinhis and Professor W. B. Banage for Nauk. SSSR (ser. Biol.) No. 6: 793-801. the specimens of the new species described (English summary p. 801). here. Seinhorst, J. W. 1968. Trichotylenchus rhopalocercus n. comb. (syn. Tylenchorhynchus Literature Cited rhopalocercus Seinhorst, 1963) and Tylen- Allen, M. W. 1955. A review of the nematode chorhynchus clavicauda nom. nov. (syn. T. genus Tylenchorhynchus. Univ. Calif. Publs. clavicaudatus of Seinhorst, 1963). Nemato- Zool. 61: 129-165. logica 14: 596. , and S. A. Sher. 1967. Taxonomic Tarjan, A. C. 1964. A compendium of the problems eoncerning the phytoparasitie nema- genus Tylenchorhynchus (Tylenchidae: Nem- tocles. Annual Rev. Phytopath. 5: 247-264. atoda). ' Proc. Helm. Soc. Wash. 31: 270- Filipjev, I. N. 1934. Harmful and useful 280. nematodes in rural economy (In Russian). Thorne, G., and R. B. Malek. 1968. Nema- Moscow/Leningrad, 440 pp. todes of the Northern Great Plains. Part I. . 1936. On the classification of the Ty- Tylenchida (Nemata: Secernentea). Tech. lenchinae. Proc. Helm. Soc. Wash. 3: 80-82. Bull. 31, S. Dak. St. Univ. Ill pp.

World Federation of Parasitologist SECOND INTERNATIONAL CONGRESS OF PARASITOLOGY Mayflower Hotel, Washington, D. C. 20036 U. S. A. 6-12 September 1970 Special Announcement to Students As announced in the Proceedings (36: 285, July 1969) the regular registration fee for this Congress is 30 U. S. dollars for preregistration during 1969, 40 U. S. dollars January 1 to August 31, 1970, and 50 U. S. dollars thereafter. In order to encourage bona fide full time students to attend the Congress a special rate of $10.00 is announced. This rate is effective any time and includes all materials and privileges covered by the regular registration. However, students are urged to register well in advance of the Congress since the special rate is allowed only with certification on the registration form. For registration forms (specify student) write to: Dr. G. F. Otto, Secretary General 2nd I.C.P., Department of Zoology, University of Maryland, College Park, Maryland 20742, U.S.A.