Mysidacea from Coastal Waters of Iriomote Island, Ryukyu Islands, Southwestern Japan, with Descriptions of Three New Species

Abstract

Fifteen mysid species, including three new species, are reported from Iriomote Island, Ryukyu Islands, Japan. A new species, Iiella iriomotensis, is distinguished from related species by the shapes of the rostrum and the telson cleft, the number of spines arming the frontal margin of the labrum, and the endopod of the uropod being shorter than the exopod. Nipponomysis minuta, new species, closely resembles Nipponomysis imparis in respect to the fourth male pleopod, but is distinguished by the shorter telson and the smaller number of spines on the lateral margin of the telson and on the inner margin of the endopod of the uropod. Anisomysis hashizumei, new species, is distinguished from related species by a combination of characters found in the fourth male pleopod and the telson. Haplostylus pusillus, which has been known only from the Indian Ocean, is reported from the Pacific Ocean for the first time. Four species, Siriella inornata, S. anomala, Anchialina zimmeri, and Pseudanchialina pusilla are new records from Japanese waters.