Superfamily ATYLENCHOIDEA Golden, 1971
This superfamily was established by Golden, 1971 for the tylenchids in the family Atylenchidae. This family contains only 2 genera and the character, "setae on the head", is the main basis for this superfamily. In our opinion, other characters are also important: longitudinal ridges on the body, tail always filiform, ovary single. With these added characters emendating the diagnosis, the superfamily may contain other genera.
Superfamily Atylenchoidea
Diagnosis (emended):
Tylenchina
Body always with longitudinal ridges, vermiform, and usually
coarsely annulated. Head with or without setae. Ovary single. Tail
filiform.
Type and only family: Atylenchidae Skarbilovich, 1959
Diagnosis (emended):
Atylenchoidea
- Cuticle with longitudinal ridges, and usually coarsely annulated
- Long setae may be present on head region
- Ovary single
- Tail filiform
- Male with or without bursa
Type subfamily: Atylenchinae Skarbilovich, 1959
KEY TO GENERA
1. Head with setae................................................................................................................................. 2
Head without setae............................................................................................................................ 3
2. Lip region not set off, bursa absent..................................................................................... Atylenchus
Lip region set off, bursa present........................................................................................ Eutylenchus
3. Body without transverse annulation except in
anterior-most end................................................................................................. Campbellenchus
Body with transverse annulation all over the body............................................................................... 4
4. Body with 10 longitudinal ridges, vulva with
ventral flap............................................................................................................ Pleurotylenchus
Body with 12-22 longitudinal ridges, vulva with
lateral flaps................................................................................................................... Coslenchus
A. Subfamily Atylenchinae Skarbilovich, 1959
Head with 4 setae
ATYLENCHUS Cobb, 1913 Figure
Atylenchinae
- Lip region not set off from body, annulated
- Cuticle bearing 10 longitudinal ridges in adult, lateral
ridges higher than other ridges.
- Male without caudal alae
Type species: Atylenchus decalineatus Cobb, 1913
EUTYLENCHUS Cobb, 1913 Figure
Atylenchinae
- Body round in cross section
- Lip region set off from body, not annulated
- Cuticle bearing 12 similar longitudinal ridges on most of body
divided into blocks by transverse striae
- Male with conspicuous caudal alae
Type species: Eutylenchus setiferus Cobb, 1913
REFERENCES:
Choi, Y.E., and E. Geraert. 1972. Some remarkable Tylenchida from
Korea. Nematologica 18:66-73.
Cobb, N.A. 1893. Plant diseases and their remedies: Diseases of the
sugar cane. Agric. Gaz. N.S.W. 4:777-833.
Cobb, N.A. 1913. New nematode genera found inhabiting fresh water
and non-brackish soils. J. Wash. Acad. Sci. 3:432-444.
Husain, Z., and S.H. Khan. 1968. A new species of the genus
Eutylenchus Cobb, 1913 (Nematoda: Atylenchidae) from India. Ann. Epiphyties 19:331-334.
Sher, S.A., D.C.M. Corbett, and R.C. Colbran. 1966. Revision of the
family Atylenchidae Skarbilovich, 1959 (Nematoda: Tylenchoidea). Proc. Helminthol. Soc. Wash. 33:60-66.
B. Subfamily Pleurotylenchinae Andrassy, 1976
(Campbellenchinae Wouts, 1977)
Head without setae
CAMPBELLENCHUS Wouts, 1977. Figure
- Amphids slit-like on lateral lips with large pouches
- Stylet long, slender, more than 20 ?m
- Vulva, slightly posterior to mid-body
- Gonad prodelphic, usually with double reflex, distal end
occasionally reaching or penetrating esophageal region
- Lateral field obscured by longitudinal striae
- Body without transverse annulation except in anterior-most end,
never past stylet base. Cuticle tesselate where longitudinal
striae meet this zone.
- Phasmids not observed
- Tail filiform
Type species: Campbellenchus poae Wouts, 1977
Note: With the absence of annulation on the body and the presence of
longitudinal striation, Wouts placed this genus in a new
subfamily, Campbellenchinae
REFERENCES:
Wouts, W.M. 1977. Campbellenchinae (Nematoda: Tylodoridae), a new
subfamily from Campbell Island, with a description of two new species. New Zealand J. Zool. 4:213-216.
PLEUROTYLENCHUS Szczygiel, 1969 Figure
(Tylenchinae)
- Cuticle coarsely annulated with 10 prominent longitudinal ridges
- Lip region with deep transverse striae
- Stylet strong, knobs well developed
- Median bulb well developed with valve
- Terminal bulb distinctly set off from intestine
- Gonad prodelphic; one species without post-vulva uterine sac
- Vulva post-equatorial with ventral flap directed backwards
- Male with adanal bursa
Type species: Pleurotylenchus sachsi (Hirschmann, 1952) Szczygiel,
1969
Note: This genus was placed in the new subfamily Pleurotylenchinae
(Atylenchidae) in 1976 by Andrassy. In 1980 Raski et al.
placed the genus in the subfamily Atylenchinae (Tylenchidae).
REFERENCES:
Andrassy, I. 1976. Evolution as a basis for the systematization of
nematodes. London, Oitman Publ.
Raski, D.J., A.R. Maggenti, P.K. Kosky and V.K. Sosamma. 1980.
Epicharinema keralense n. gen. n. sp. and comments on Atylenchinae and Ecophyadophorinae (Nemata: Tylenchidae). Revue Nematol.
3:297-304.
Siddiqi, M.R. 1978. The unusual position of the phasmids in
Coslenchus costatus (deMan, 1921) gen. n. comb. n. and other Tylenchidae (Nematoda: Tylenchida) Nematologica 24:449-455.
Szczygiel, A. 1969. A new genus and four new species of the
subfamily Tylenchinae deMan, 1876 (Nematoda: Tylenchidae) from Poland. Opusc. Zool. Budapest 9:159-170.
COSLENCHUS Siddiqi, 1978. Figure
(Tylenchinae, Pleurotylenchinae)
- Small nematodes
- Cuticle coarsely annulated, 12-22 longitudinal ridges present,
excluding the ridges of lateral fields, thus, surface of the
cuticle appears as squares or rectangles.
- Lip region striated
- Stylet less than 15 ?m long, conus less than half its length
with rounded basal knobs
- Esophagus valvate, not overlapping intestine
- Vagina at right angle to body axis. Uterine sac rudimentary
- Lateral flap present, sometimes rudimentary.
- Phasmids dorsal, sublateral post median near vulva in female
- Tail very elongate conoid to filiform
- Male with adanal bursa, cloaca lips form a short tube
Type species: Coslenchus costatus Siddiqi, 1978
Note: This genus was formed from Aglenchus costatus
REFERENCES:
Siddiqi, M.R. 1978. The unusual position of the phasmids in
Coslenchus costatus (deMan, 1921) gen. n. comb. n. and other Tylenchidae (Nematoda: Tylenchida). Nematologica 24:449-455.
