Eight New Records of Siphonophores (Cnidaria: Hydrozoa) in Korean Waters

Abstract

Taxonomical research on siphonophores is lacking despite their high biodiversity. We collected siphonophores in Jeju and the southern coasts of Korea and conducted morphological redescriptions using multi-focus stacked digital images. As a result, we revealed eight unrecorded siphonophores (Abyla haeckeli, Ceratocymba leuckartii, Bassia bassensis, Dimophyes arctica, Lensia subtilis, Lensia subtiloides, Muggiaea atlantica, and Nanomia bijuga). Six genera, excluding Muggiaea, were reported for the first time in Korean waters, and subfamily Abylinae, to which Abyla haeckeli and Ceratocymba leuckartii belong, was also first recorded in Korea. The distributions and habitats of these species were summarized, with most of the species having cosmopolitan distributions but variations in individual size depending on environmental conditions. Phylogenetic analysis based on mtCOI was conducted for each family. Finally, we updated the species list of siphonophores in Korean waters to include 3 suborders, 5 families, 3 subfamilies, 14 genera, and 21 species. Our findings constitute baseline data for further research on Korean siphonophores.