Odontosyllis octodentata n. sp.
A relatively large species, approximately 40 mm. long and 2.5 mm. in width.
The prostomium (plate 1, fig. 1) is broader than long, with the anterior margin broader than the posterior, the lateral angles rounded. The posterior margin has a slight depression which is not shown in the figure because a lobe from the anterior margin of the peristomium extends over it. The paips are separate from one another, and prominent, not sharply separated from the prostomium, so that they seem almost to be forward prolongations of it. Eyes 2 pairs, brown, anterior pair the larger and farther apart than posterior pair. The median tentacle was noticeably more slender than the lateral and none of these extends much beyond the tip of the palp. None of the tentacles were well preserved and I am uncertain as to their normal appearance.
Pharynx short, with ventrally a row of 8 subequal teeth. The peristomium
is prolonged dorsally into a broad lobe which covers the posterior surface of the prostomium. Tentacular cirri are slender, the dorsal ones being the largest. Dorsal cirri of later somites similar in form but successively smaller.
Parapodium (plate 1, fig. 2), with its end prolonged into equal anterior and posterior lobes and with an acicula with its apex coming to the surface just dorsal to these. Ventral cirrus ovate in outline, shorter than setigerous lobe. Dorsal cirrus long and slender. The seta (fig. 3) with a very long basal joint, the longest reaching nearly halfway to the end of the dorsal cirrus. Terminal joint with a very short terminal and a single subapical tooth. Apex of basal portion with minute denticulations.
Type in American Museum of Natural History.