Cossura longocirrata Webster & Benedict, 1887

Synonyms:
No synonyms.

Distinguishing characteristics
Prostomium is conical.
Single, very long branchial filament arising from chaetiger 2 or 3.
Abdomen like a string of beads.
Pygidium with 3 cirri.

Species description
Body is long and cylindrical, divided in three regions. Prostomium is conical, rounded at the tip. Mouth ventral. A single, very long branchial filament arising from posterior margin of chaetiger 2. Parapodia are rudimentary. Thorax with 16-21 short segments, abdomen like a string of beads, with a marked constriction between segments. 20-40 abdominal chaetigers, last few segments without chaetae. Pygidium with 3 cirri, without intercirral processes or free lobes.

Size
Up to 19 mm for 85 segments.

Color
Colourless.

Habitat
Usually in mud, sometimes in muddy sand.
7 to 900 m.

Mobility
Mobile.

Feeding
Surface deposit feeder.

Life cycle

Distribution
Arctic, North Pacific, North Atlantic, Skagerrak, Kattegat and Öresund.