A new Notomastus (Annelida, Capitellidae) species from Korean waters, with genetic comparison based on three gene markers

Notomastus koreanus sp. n., collected from the sublittoral muddy bottom of Korean waters, is described as a new species. The Korean new species closely resembles N. torquatus Hutchings & Rainer, 1979 in the chaetal arrangement and the details of abdominal segments, but differs in the position of genital pores and the absence of eyes. DNA sequences (mtCOI, 16S rRNA, and histone H3) of the new species were compared with all the available sequences of Notomastus species in the GenBank database. Three genes showed significant genetic differences between the new species and its congeners (COI: 51.2%, 16S: 38.1–47.3%, H3: 3.7–9.3%). This study also includes a comprehensive comparison of the new Korean Notomastus species with its most closely similar species, based on the morphological and genetic results.