Bristleworm

S. filicornis probably spawns in autumn or winter, releasing large eggs. Planktonic larvae are found from February to April. S. filicomis builds fragile tubes of sand fragments. lt swims in spirals when disturbed. Spionids are generally considered surface deposit feeders that use their large ciliated palps to select and pick up food particles (Hartmann-Schröder, 1971; Curtis, 1977; Hayward & Ryland, 1990).

In Gulf of St. Lawrence, Canada [identity of the Spio of the distribution described needs to be re-evaluated - ed.] southern Gaspe waters (Baie des Chaleurs, Gaspe Bay to American, Orphan and Bradelle banks; eastern boundary: eastern Bradelle Valley), downstream part of middle St. Lawrence estuary, lower St. Lawrence estuary; Magdalen Islands (from Eastern Bradelle valley to the west, as far as Cape North, including the Cape Breton Channel); Cobscook Bay to Cape Cod

As redescribed (Meißner et al, 2011) so far known only from Iluilârssuk (neotype locality) and Paamiut (Frederikshaab),West Greenland. See Spio arndti (Western Baltic Sea) and Spio symphyta (North Sea and perhaps Norwegian Sea). Spio 'filicornis' elsewhere may be other species although quite similar in appearance.

bathyal, infralittoral and circalittoral of the Gulf and estuary

The density distribution of this species suggests a preference for the sandy types of sediment with little mud, although other sediment types are inhabited as well. The species has for instance been reported from anoxic mud (Hartmann-Schröder, 1971; Hayward & Ryland, 1990).

A thin and fragile species with a maximum length of 30 mm and about 2 mm wide. The body is composed of up 90 uniform segments. The head bears four small eyes arranged in a square and two palps. Finger-like, dorsally curved gills are present from the first to almost the last segment. The colour of the body is bluish green with contrasting red blood vessels in the palps and the gilis. Mature males are whitish, while females are brighter green (Hartmann-Schröder, 1971; Hayward & Ryland, 1990).