Bathynellinae

Subfamily Bathynellinae

Diagnosis (translated from Serban et al. 1972)

Mandibular palp always three-segmented; masticatory part of mandible with four teeth on pars molaris [molar process], two teeth on pars incisiva [incisor process], and accessory incisor process (processus incisivus accesorius [accessory incisor process]) formed by one tooth and sometimes small denticles. Endopod of thoracopods four-segmented. Penial region of male ThVIII composed of several lobes forming the penial complex, a frontal projection, inner and outer lobes which can sometimes be merged into a fourth, parapenean lobe (papilla); basipod well developed and merged to the penial complex on anterior side of the proximal region, with main axis parallel to penial lobes; endopod and exopod present and one-segmented. Two-segmented protopod (coxa and basipod) in female ThVIII, with precoxa and coxal epipod; endopod formed by a single short segment; one-segmented exopod well developed and similar to the exopod of other thoracopods.

Type genus: Bathynella Vejdovsky, 1882 .

Remarks

The subfamily Bathynellinae includes 11 genera and an undetermined number of species, ~65, 45 of which have been identified as members of the ‘catch-all’ genus Bathynella . However, in many species assigned to this genus, the male ThVIII is unknown or poorly described, making a comparison very hard. For a more exhaustive explanation of the ‘ Bathynella issue’, see Camacho et al. (2018b) and Perina et al. (2018).

A thorough morphological and molecular revision is needed to resolve the taxonomic problems within Bathynellinae , which is beyond the scope of this study. The confirmed distribution of the genus Bathynella includes the areas between Transcaucasia and the North of France (Serban 1975, 2000).