A New Record of the Brittle Star, Amphistigma minuta (Ophiuroidea: Amphilepidida: Amphiuridae), from Jeju Island, Korea

Abstract

The brittle star, Amphistigma minuta H.L. Clark, 1938, was collected from Munseom Island, Jeju­do, Korea, by SCUBA diving. This species has distinct morphological features, as follows: a small disk with large papillae on the disk margin; slender arms and four arm spines at proximal; and oral parts the same as those of the genus Amphipholis. Additionally, we obtained partial sequences of the cytochrome c oxidase subunit I gene (COI) (513 bp) and compared them with sequences from Australian A. minuta and 13 other species of Amphiuridae. As a result, intraspecific pairwise distance was 0.4% between two Korean individuals and intraspecific distance between the Australian and the Korean populations was 2.6-2.8%, which indicates they should be considered as the same species. Ultimately, 15 species of the family Amphiuridae have currently been recorded in Korea, including A. minuta.