Long worms with a slightly flattened and broader anterior region bearing lateral parapodia and a rounded, more fragile posterior region bearing its parapodia dorsally. Parapodia biramous, with well-developed lobes.
Prostomium conical, rounded or truncate, without appendages.
Peristomium a complete ring without appendages or chaetae.
First segment similar to following segments with similar parapodia.
Aciculae present in posterior parapodia. No dorsal or ventral cirri.
Chaetae variously ornamented capillaries and spines. Broad, lanceolate, simple gills are present dorsally on all but the first few segments.
The main genus Orbinia has, as anterior neuropodium, tori, which contain crochets in several rows, fringed behind by a row of post-chaetal papillae. A number of segments at the junction of the anterior and posterior regions also have, on each side, a row a subpodial papillae, which can meet in the ventral mid-line.
In genus Scoloplos, there are markedly fewer post-chaetal and subpodial papillae; crochets may be present on all, a few, or none of the anterior segments. Only few members of the family completely lack subpodial papillae.
Pygidium with two or more long, threadlike cirri (Orbiniidae).
After: Fauchald and Rouse, 1997 and Hayward and Ryland, 1990.
For identification to species level, jump to the Picture key: Page 119: Orbiniidae
The following taxa of this family occur in the region: