Comprehensive DescriptionRead full entry
“Weddellia profunda, new species
Record: 15:6 sta. 610 (3, TYPE).
Description: A tube with enclosed animal measures 60 mm long by 6 mm wide; it is externally covered with silt, thin-walled, limp, and the tube loosely surrounds the animal. The enclosed animal is 35 mm long by 4 mm wide in its thoracic region (Fig. A), and it tapers posteriorly to a long, slender abdominal end. The thorax has 18 and the abdomen 23 setigerous segments; they are followed by three or four obscure segments without parapodia or setae, and the terminal pygidium has a thick, fleshy flange.
The prostomium is broadly rectangular; it has a pair of lateral lobes (Fig. B) which extend forward beyond the median part. The next segment, or peristomium, is much larger and encompasses the prostomium along its posterior and lateral margins; ventrally it forms a thick fold or lower lip (Fig. C) beneath the folded oral membrane. From its dorsal side emerge the cylindrical oral tentacles, all of one kind and nearly as long as the branchiae.
The first five to seven thoracic segments are short, broad and resemble one another in having slender, thoracic setal fascicles; the first three are also branchial ; each has a branchia inserted within the setal fascicle and they leave a broad middorsum exposed. Uncini are first present from the fourth setiger; they occur in transverse single rows. Each one is a thick plaque with marginal teeth (Fig. F) with three larger teeth surmounted by a circlet of smaller ones (Fig. E). Abdominal parapodia are unique for having a long, cirriform process, resembling a dorsal cirrus (Fig. D), above the uncinigerous torus; these cirri continue posteriorly to the end. Abdominal uncini resemble thoracic uncini but are shorter and blunter; each has large teeth in several rows along the cutting edge (Figs. G, H).
Weddellia profunda is named for its source near the great Weddell Sea, from which several unique polychaetes have been recovered.
Distribution: South Sandwich Basin, in 2553-2575 m.”