Body of this scale-worm small, narrow tapering posteriorly. Dorsal surface smooth with a few pairs of ctenidia on anterior segments, ventral surface papillate.
Prostomium rounded, with a median antenna with large basal joint with an ear-shaped process on either side, two pairs of eyes and a pair of palps. First segment with numerous capillary chaetae, a pair of small lateral antennae, a pair of ctenidia on the mid-dorsal surface, a pair of lamellae on the inner surface and a pair of long dorsal and short ventral tentacular cirri. Scales occur on segments 1, 3, 4 and 6, then alternately to the 26th and then on all segments. Scales are round to kidney-shaped with papillae on the margins and small tubercles on the surface. Three ctenidial cushions attached to the dorsal surface of notopodia appear on all segments except the Ist and 2nd segments which have two. Cirriform gills occur above the ctenidial cushions on all chaetigers from the 3rd. Ventral cirri present on all segments and between the cirri and the body wall a small ctenidium occurs. Notopodia with a group of terminal finger-like projections and numerous chaetae. Notopodial chaetae long spinose capillaries. Neuropodia extend as far as notopodia with terminal papillate finger-like projections and a sinuous row of chaetae. Neuropodial chaetae compound with multiarticulate blades, bidentate tips, and spinose shafts (S. zetlandica-detail).
Up to 9 mm for 29 chaetigers (incomplete).
Sublittoral to 558 m, on coarse sand and shell.
Northeast Atlantic between Shetland and Cape Verde islands, northern North Sea, Skagerrak, South Africa.