Body transparent and flaccid with a conspicuous neck and broad head. Two pairs of lateral fins, separated and only partially rayed. Collarette and alimentary diverticula absent. Eyes small, with a star-shaped pigment spot.
Ovaries short and broad; ova relatively large. Testes situated at the posterior end of the tail segment only. Seminal vesicles small and round, at some distance from the posterior fins and touching the tail fin.
Hooks 8-10. Teeth in two rows, anteriorly 4-10, posteriorly 4-15.
Maximum body length 25 mm, relative tail length 14-17%.
Distribution in the North Sea
S. enflata might occur in the northern North Sea, entered from the adjacent North East Atlantic waters.
Epipelagic in warm and temperate oceanic waters. The species has been recorded from inshore neritic waters.
[After Pierrot-Bults and Chidgey, 1988]