Clam Worms

The prostomium (right) has two antennae and two large, two-segmented palps. The peristomium (segment behind the prostomium) has 4 pairs of tentacular cirri. This photo is a 3d composite made from a series of photos using a Keyence digital microscope. Photo by Dave Cowles, July 2009

This dorsal view of the posterior body shows the prominent, straplike ligules with attached terminal cirrus which are characteristic of this species.

This dorsal view of the parapodia shows the small aciculae with larger ventral and even larger dorsal lobes (ligules).

Most of the setae are compound (composed of more than one segment). Closer examination by compound microscope would show this to be a homogomph falcigerous seta. A falciger is a seta in which the tip is comparatively blunt and curved. A homogomph seta is a compound seta in which the basal segment ends in a slightly expanded capsule, the two sides of which are of approximately equal height (as opposed to heterogomph, in which one side of the capsule is extended well out past the other).

Nereis vexillosa, about 24 cm long, found at Padilla Bay. (Photo by: Dave Cowles, July 2009 )