Abstract

The family Ameiridae Boeck, 1865 (Copepoda; Harpacticoida) consists of about 380 species in 47 genera, but only 10 species have been reported in Korea. A benthic ameirid species was collected from the East Sea of Korea. Specimens were identified as members of the genus Ameiropsis Sars G.O., 1907, and this is the first record of the genus Ameiropsis in the Pacific Ocean. Ameiropsis gyeongjuensis sp. nov. is morphologically similar to A. mixta Sars G.O., 1907 and A. longicornis Sars G.O., 1907 from Norway. However, the new species is clearly distinguishable from the others based on the following morphological characteristics: the proximal segment of antennary exopod with a bulge in the middle, and with one pinnate seta; the distal segment of antennary exopod with a thickened, blade-shaped outer seta; and female P5 baseoendopod with five setae and exopod with six setae. An identification key to species is provided for the 11 valid species of the genus Ameiropsis.