- no.13, pp.1-12, 2000-03
Chaetopterus gregarius new species (Polychaeta: Chaetopteridae) is described from 120-300m depth off Tokyo Bay, Central Japan. The new species is gregarious and probably epifaunal; masses of irregularly U-shaped, tough, parchment-like tubes were recovered from hard substrata. The species is oculate, of moderate size (up to 57mm long), with 9A+5B+16-23C segments. It appears to differ from other members of the genus in having two kinds of notopodia in region C. When live specimens were placed in fresh water, bioluminescence was seen in the palps and alate (winglike) notopodia of B1, with the most long-lasting and brilliant light at the base of the B1 notopodia. No other areas luminesced. This pattern appears to differ from ones reported from other members of the genus, most of which have been (incorrectly) identified as C. variopedatus.