A new genus and species of Syllidae (Annelida: Polychaeta) from Australia with unusual morphological characters and uncertain systematic position

In this paper the description of Murrindisyllis kooromundroola, an enigmatic new genus and species of Syllidae (Polychaeta), is given. The new genus is characterized by having palps totally fused that are also fused with the prostomium, a single pair of eyes, a distinctly long, coiled median antenna, segments of the midbody with 2 or 3 chaetigers fused, dorsal cirri of the midbody smooth, ending in a webbed, "hand-like" structure, interiorly maintained by five rows of vacuolated cells, similar in shape to a frog's "foot," simple chaetae on posterior segments produced by partial fusion of unidentate blades with the shafts, an unarmed pharynx, and a very long proventricle. These very unusual characters are unique among the syllids; webbed, "hand-like" structures on dorsal cirri are also unique among polychaetes. The combination of different characters assigned to different subfamilies and the presence of distinctive and unique features makes the systematic position of the new genus in the family Syllidae uncertain.