Two new interstitial species of the genus Parapolycope (Crustacea: Ostracoda) from central Japan

Two new interstitial cladocopid ostracods are described from central Japan: Parapolycope oligohalina sp. nov, and Parapolycope spiralis sp. nov. These two species are the third and forth records of the genus Parapolycope Klie, 1936, respectively. Since P. oligohalina sp. nov. inhabits river mouth environments with low salinity at low tides, the wide tolerance to salinity in the species is shown. Myodocopan Ostracoda have so far been considered as a pure marine taxa. The occurrence of P. oligohalina sp. nov. indicates that a few myodocopan ostracods can live in oligohaline environments. The carapace surface covered with puncta of varying size is a unique character of P. oligohalina sp. nov. P. spiralis sp. nov. exhibits a spiral structure in both male copulatory duct and female spermatheca as specific characters. A key to the genera of the Polycopinae is presented.