Cypridopsinae, Kaufmann, 1900

Savatenalinton, Sukonthip, 2017, Siamopsis gen. nov. and five new species of the subfamily Cypridopsinae Kaufmann, 1900 (Crustacea: Ostracoda) from Thailand, European Journal of Taxonomy 384, pp. 1-39 : 34-35

Key to genera with RV overlapping LV in the subfamily Cypridopsinae

1. CR absent in both male and female ……………………… Martenscypridopsis Karanovic, 2000

– CR present in female ………………………………………………………………………………2

2. CR of cylindrical shape ……………………………………………………………………………3

– CR of triangular shape ……………………………………………………………………………5

3. RV with well developed septa beneath posterior inner list ………… Klieopsis Martens et al., 1991

– RV without well developed septa beneath posterior inner list ……………………………………4

4. Internal LV with a plate-like protrusion on the postero-dorsal part, two t-setae on female A2 …… ………………………………………………………………………………… Siamopsis gen. nov.

– Internal LV without a plate-like protrusion on the postero-dorsal part, four t-setae on female A2 … ……………………………………………………………………… Plesiocypridopsis Rome, 1965

5. Valves very elongated (L/H> 2), posterior selvage of internal LV displaced substantially to the front … …………………………………………………………… Tanganyikacypridopsis (Martens, 1985)

– Valves not very elongated (L/H <2), posterior selvage of internal LV not displaced substantially to the front …………………………………………………………………………………………6

6. A2 natatory setae long, carapace subtriangular …………………… Sarscypridopsis McKenzie, 1977

– A2 natatory setae short, carapace not subtriangular (mostly more subovate) ………………………7

7. RV without inner list, left prehensile palp with slender finger-like terminal segment, terminal segment of Mx1 palp with (slightly) enlarged tip ……… Thermopsis Külköylüoğlu et al., 2003

– RV with inner list, left prehensile palp without slender finger-like terminal segment, terminal segment of Mx1 palp without enlarged tip ………………………………………………………8

8. Left prehensile palp with terminal segment enlarged distally, terminal segment of Mx1 palp very elongated (L/W> 2) ………………………………………………………… Bryocypris Røen, 1956

– Left prehensile palp without terminal segment enlarged distally, terminal segment of Mx1 palp not very elongated (L/W <2) ……………………………………… Kapcypridopsis McKenzie, 1977