Surveys of species diversity in sublittoral waters along the coasts of the Cape Peninsula on the Atlantic coast of South Africa yielded three species of Mysidopsis G.O. Sars, 1864. A new species, M. abbreviata n. sp., is described, a supplementary description is given for M. similis (Zimmer, 1912), and the female of M. zsilaveczi Wittmann & Griffiths, 2014 is described for the first time. The new species is characterized, among other characters, by a transversely shortened rostrum. Field observations of M. zsilaveczi and M. abbreviata n. sp. showed the greatest intraspecific diversity of colour patterns ever documented for mysids. Stomach contents, together with differences in the armature of perioral mouthparts and in the foregut, suggest that all three species are specialized predators, mainly of crustaceans. An updated key to the species of Mysidopsis in southern Africa is given. |