ON MORPHOLOGY AND PHYLOGENY OF PELAGOBIA LONGICIRRATA (POLYCHAETA, ANNELIDA)

The morphology and anatomy of the pelagic polychaetous worm, Pelagobia longicirrata (Greef 1879), from the Southern ocean (Drake Strait) are described using histological methods and both light and scan electronic microscopy. An anterio-ventral gland complex and special ciliate fields are described for the first time. The presence of pharyngeal jaws, which needed a confirmation, is stated. The phylogenetic analysis of the material collected is performed with the 18S rDNA gene. Lopadorrhynchidae is a monophyletic group; Phyllodocidae is its sister group. Pelagobia longicirrata contains at least two species. The samples studied differ in morphological and genetic features from those described earlier in other sites.