Abstract
Based on examination of the holotype, new collections from the type locality and other regions of the Kara and East Siberian Seas, an illustrated redescription of Trochochaeta carica is presented. Some morphological details, including the shape of the pygidium, eggs, sperm, and laIVae are described for the first time. Specimens were found in reproductive condition in the middle of August. Mature eggs measuring up to 500 x 564 and 405 x 650 11m in diameter and containing large quantities of yolk granules are spawned in maternal tubes. Spermatozoa have a round head, measuring 3.3 11m in diameter. The 21-segment larvae were still in the tubes of the adults. This laIVal stage is characterized by an outspread ‘umbrella’, a terminally notched prostomium without eyes, 11 pairs of well developed parapodia, two pairs of coarse setae in segment three, long provisional swimming setae and a four-lobed pygidium. The presence of long swimming setae in the laIVae suggests a pelagic stage, which is important for dispersion oftubicolous species. The type of development is apparently entirely lecithotrophic. North Atlantic specimens, identified by PEITIBONE (1976) as T. carica, are more closely related to T. pettiboneae Dean, 1987. We suggest that the distribution of T. carica is limited to Arctic Seas.
