| Six new species of the genus <i>Richtersia</i> Steiner, 1916 are described from the Mediterranean Sea: <i>R. bathyalis</i> sp.n., <i>R. spinosa</i> sp.n., <i>R. heipi</i> sp.n., <i>R. mediterranea</i> sp.n., <i>R. staresensis</i> sp.n. and <i>R. coomansi</i> sp.n. Some morphological adaptations of <i>R. bathyalis, R. spinosa</i> and <i>R. heipi</i> are discussed in relation to their small body size. The structure of the stomatal region, labial region and spicules is described in detail and probably holds for the entire genus. |
