Zoological Studies

Chaetopterid Polychaetes from Taiwan and Okinawa Island (Japan), with Descriptions of Two New Species

Eijiroh Nishi and Hwey-Lian Hsieh (2009) Chaetopterid polychaetes (Annelida: Spionida) were studied in shallow-water sandy and muddy areas of Taiwan and Okinawa I., Japan.  We found 4 species of the family, Mesochaetopterus japonicus Fujiwara, 1934, M. formosana sp. nov., Phyllochaetopterus verrilli Treadwell, 1943, and P. awasensis sp. nov.  The former 3 species were found in Taiwan, and the latter 2 species at Okinawa.  Mesochaetopterus formosana sp. nov. is characterized by having 2 middle-region (region B) chaetigers.  These middle-region chaetigers are very long resulting in the middle region being 1.5-2 times longer than the anterior region (region A).  Region A has 6-8 A4 modified cutting chaetae that have both small and large teeth on the head.  Phyllochaetopterus awasensis sp. nov. is characterized by having 13 or 14 region A chaetigers, approximately 20 region B chaetigers, A4 chaetae with small teeth on the edge of the heads, and a tough brown chitinous tube.  These are the first records of Mesochaetopterus japonicus and P. verrilli in Taiwanese waters.   We compared the species reported here with other Pacific chaetopterids.