Westheide, 1967
Description:
Body slender. Compound refractive glands with 5-10 parts; bacillary glands elongate. Trunk comprises two segment-like rings behind the prostomium, plus five segments, most posterior of which is indistinctly separated from pygidium.
Contours of prostomium more oval than in Trilobodrilus heideri . Four bristle-like groups of adjoined sensory cilia and numerous single cilia on anterior part of prostomium.
Fist ciliary ring dorsally complete, except for small median interruption.
Second ring broader, consisting of two dense rows of cilia, at level of lateral swellings, dorsally incomplete with a wide dorsal gap with tuft of a few scattered cilia; ventrally this ring runs into the prominent ventral ciliary field in front of the mouth. Additional row of smaller cilia behind the broad ring, posteriorly from the lateral swellings. Two lateral oval ciliary pits in groove between prostomium and first trunk ring. This ring with incomplete ciliary ring. Numerous sensory cilia, scattered all over body, concentrated on posterior end. Continuous mid-ventral ciliary groove.
Size:
Up to 0.8-1.0 mm; width about 100 µm.
Colour:
Transparent; intestine sometimes greenish.
Habitat:
A narrow zone (a few metres wide) parallel to the low water level in intertidal sand beaches and sand flats.
Distribution:
North Sea (Sylt, Amrum, Helgoland Dune, Westerschelde), French Atlantic coast (Arcachon).