Cytolaimium Cobb, 1920

Leduc, Daniel, Zhao, Zeng Qi & Sinniger, Frederic, 2020, Halanonchus scintillatulus sp. nov. from New Zealand and a review of the suborder Trefusiina (Nematoda: Enoplida), European Journal of Taxonomy 661 (661), pp. 1-45 : 16-17

Genus Cytolaimium Cobb, 1920

Diagnosis (modified from Cobb 1920 and Ott 1977)

Trefusiinae . Cuticle smooth. Outer labial setae jointed, much longer than cephalic setae; cephalic setae situated at posterior edge of, or posterior to, amphids. Amphids circular, cryptospiral or unispiral. Buccal cavity small to medium-sized, funnel-shaped, not cuticularized. Pharyngeal supplements absent. Pairs of discoid supplements present in pre- and post-cloacal regions. Female reproductive system didelphic with two opposed reflexed ovaries (outstretched in Cytolaimium exile ). Male reproductive system diorchic. Tail conical, conico-cylindrical or filiform. Two species.

Type species

Cytolaimium exile Cobb, 1920 .

Other valid species

C. gerlachi Ott, 1977 . = Cytolaimium exile Cobb, 1920 sensu Gerlach, 1962 .

Remarks

Cytolaimium is similar to Trefusia but can be distinguished from the latter by the presence of pairs of discoid supplements in both pre- and post-cloacal regions. Gerlach (1962) synonymized C. obtusicaudatum Chitwood, 1936 with C. exile . This was not accepted by Ott (1977) who considered the two species to be morphologically distinct. Gerlach & Riemann (1973 /74) moved Trefusia conica Gerlach, 1957 to Cytolaimium ; however, this species lacks the discoid supplements and is therefore considered to belong to Trefusia ( Ott, 1977) . Ott (1977) reviewed the genus and provided a key to species. The latter author also erected C. gerlachi to accommodate the specimens described by Gerlach (1962), which he deemed morphologically distinct from C. exile . Ott (1977) moved Rhabdocoma articulata to Cytolaimium , but because this species is known from a juvenile only, we consider it species inquirenda.