Rhips Cobb, 1920

Venekey, Virag, Gheller, Paula F., Kandratavicius, Noelia, Cunha, Beatriz Pereira, Vilas-Boas, Ana Carolina, Fonseca, Gustavo & Maria, Tatiana F., 2019, The state of the art of Chromadoridae (Nematoda, Chromadorida): a historical review, diagnoses and comments about valid and dubious genera and a list of valid species, Zootaxa 4578 (1), pp. 1-67 : 27-28

Genus Rhips Cobb, 1920

The genus Rhips was proposed by Cobb (1920) with the description of R. ornata . Timm (1961) described R. longicauda and Platt & Zhang (1982) described R. paraornata . They considered R. longicauda as a dubious species since its description was based on a poorly described single immature female. Subsequently, four species were added to the genus: R. anoxybiotica by Jensen (1985), R. carenata by Pastor de Ward (1985) and R. galapagensis and R. gracilicauda , both described by Blome (1985). Kulikov (1993) described R. orientalis and presented an identification key to the genus but some species were missing. The last species ( R. reginae ) was added to this genus by Muthumbi & Vincx (1998b). According to Kulikov (1993), members of Rhips are characterized by the large transversally elongated amphideal fovea with thickened margins of the punch, articulate spicules with two arcuate parts and the gubernaculum with two L-shaped auxiliary pieces. Muthumbi & Vincx (1998b) discussed differences between Rhips and Actinonema and commented about the spicules loss in some males of Rhips —the fact that makes it difficult the distinction of these two genera.

Diagnosis (modified from Muthumbi & Vincx 1998b and Tchesunov 2014): Heterogeneous cuticle with lateral differentiation as a narrow ridge beginning at the end of the pharynx. Six outer labial sensilla and four cephalic setae arranged in a common circle. Amphideal fovea conspicuous transversally oval with a double contour. Buccal cavity with one small dorsal tooth and two ventrosublateral teeth. Pharynx gradually enlarged posteriorly. Spicules double-jointed. Gubernaculum with lateral pieces.

Number of valid species: 8.

Genus Rhips Cobb, 1920

VALID SPECIES

1. Rhips anoxybiotica Jensen, 1985 (Gulf of Mexico)

2. Rhips carenata Pastor de Ward, 1985 ( Argentina)

3. Rhips galapagensis Blome, 1985 (Galapagos)

4. Rhips gracilicauda Blome, 1985 (Galapagos)

5. Rhips orientalis Kulikov, 1993 (Kuril Islands)

6. Rhips ornata Cobb, 1920 (Florida)

7. Rhips paraornata Platt & Zhang, 1982 ( Scotland)

8. Rhips reginae Muthumbi & Vincx, 1985 (Indian Ocean)

SPECIES INQUIRENDUM

1. Rhips longicauda Timm, 1961 (Bay of Bengal)