(Müller, 1847)
Description
Body small, narrow, flexible and transparent. Two pairs of lateral fins, separated, rounded and completely rayed. The anterior fins begin at some distance from the ventral ganglion. Collarette small or absent. Alimentary diverticula absent. Eyes with a star-shaped segment spot.
Ovaries short, with fairly large ova. Seminal vesicles close to, or touching the posterior fins, and separated from the tail fin. Vesicles consist of an elongated posterior trunk and an anterior knob.
Hooks: 8-9. Teeth in two rows, anterior 6-8 and posterior 10-16.
Size
Maximum body length 14 mm, relative tail length 16-25%.
Depth range
S. setosa is a neritic species and therefore occurs in shallow waters only.
Distribution in the North Sea
Common in the whole North Sea and inshore waters.
World distribution
Neritic, shallow waters of NE Atlantic and Mediterranean Sea.
[After Pierrot-Bults and Chidgey, 1988]