Body cylindrical, mid-body slightly swollen.
Prostomium conical, fused to the anterior segments, with 2 small black eyes. Anterior three achaetous segments dorsally fused together. One pair of long, thick palps on the last achaetous segment.
The filamentous gills are inserted dorsally starting at the 1st chaetiger. They are present on all but the very last segments. The distance between gills and notopodia is longer than between noto- and neuropodia.
Chaetae are smooth capillaries, the dorsal chaetae very fine, the ventral chaetae especially in the posterior body half, slightly shorter, thicker and slightly curved.
Up to 10 mm for 65 segments.
Yellowish-green or light pink.
From eulittoral to middle sublittoral, down to about 128 m deep.
Northeast Atlantic up to Mediterranean, North Sea.