Southern, 1914
Description:
Prostomium with four eyes in a trapezoid arrangement and sometimes with small ocelli. Palps shorter than prostomium but large and broad. Median antenna twice as long or as long as lateral antennae. Smooth lateral antennae as long as or a little longer than prostomium. Dorsal tentacular cirri a little shorter than the median antennae; the ventral one half that size. Dorsal cirri of alternating size, the long ones up to 4 times segment width, the short ones shorter than segment width. Ventral cirri large, leaf-like, and distinctly longer than parapodial lobes. Anterior parapodia with two distinct bud-shaped aciculae; other parapodia with 1 or 2 slimmer bud-shaped acicula (O. pterochaeta-parapodium). Blades of compound chaetae short and broad, bidentate with a hood. In middle and posterior parapodia an additional upper simple chaeta is present and in the posteriormost parapodia a lower simple chaeta too (O. pterochaeta-chaetae). Pharynx very long with one very large tooth near the middle.
Size:
Body up to 6 mm long for 50 or more segments.
Colour:
In alcohol yellowish to transparent, pharynx light brown.
Distribution:
North Atlantic, between Ireland and Spain, southern North Sea.