Billcypris, Halse & Martens, 2019

Halse, Stuart A. & Martens, Koen, 2019, Four new genera and five new species of ‘ Heterocypris’ from Western Australia (Crustacea, Ostracoda, Cyprinotinae), European Journal of Taxonomy 493, pp. 1-35 : 26

Billcypris gen. nov.

urn:lsid:zoobank.org:act:5256267F-1765-435D-A77F-ED6A9C24ECF2

Type species

Billcypris davisae gen. et sp. nov. (here designated).

Other species

The genus is monospecific.

Diagnosis

Valves higher in posterior half than anterior, LV overlapping RV on all sides. RV with marginal tubercles weakly developed or absent. RV with anterior and posteroventral selvage inwardly displaced. LV anteriorly with blunt inner list, parallel to valve margin. A1 with all segments of normal length/ width ratio. Second segment of Mx1 palp slightly longer than basal width, not curved. Second segment on Lpp without long distal flagellum. Seta d2 on T2 absent. CR in both male and female less curved and without swollen proximal section; attachment to CR uniramous. Hemipenis with lobe ms pointed and only developed ventrally; lobe ls large and sub-rectangular.

Etymology

This new genus is named after William ‘Bill’ Williams (Adelaide, Australia) in honour of the large contributions he has made to Australian limnology, especially in drawing attention to salt lake ecology. Bill was also the PhD supervisor of Patrick De Deckker, after whom the first new genus in this paper was named and, as such, facilitated ostracod research in Australia through Patrick’s skills and enthusiasm.

Differential diagnosis

Billcypris gen. nov. has some valve characteristics that are similar to those in Heterocypris , apart from the absence of strong marginal tubercles on the RV, but differs from all other genera in the Cyprinotinae by the structure of the hemipenis, which consists of a pointed and only ventrally developed lobe ms and a very large and sub-rectangular lobe ls.

The new genus can be distinguished from Cyprinotus by the absence of the dorsal hump on the RV, from Hemicypris and Homocypris by the fact that the LV overlaps the RV (inverse in Hemicypris ; valves symmetrical in Homocypris ) and from Riocypris by the absence of seta d2 on limb T2.

Distribution

The genus is known only from the southern Goldfields region in Western Australia.

Remarks

As usual in monospecific genera, it is difficult to determine which characters are valid at the generic level and which at the specific level. It is thus possible that the diagnosis of this new genus will have to be adapted if more congeneric species are found.