(Gmelin, 1791)
Description:
The body may reach 15 mm in extended length (usually 10-12 mm), pale
yellow or white with crimson pigment above, occasionally lining up to form
streaks or blotches. The cerata (5-8 pairs) bear 3-4 concentric circlets of rounded tubercles, each containing a small crimson spot. The dorsal surface of the body, the flanks and the head are streaked and blotched with superficial
crimson pigment. Lobes of the digestive gland penetrate the cerata, and their
reddish colour is conspicuous within the ceratal bases (a good specific recognition character). The frontal margin of the head is dilated laterally. The rhinophore sheaths are widely dilated, smooth and without pigment on the rim.
Habitat:
This species is common in shallow waters around the British Isles, feeding upon the hydroids Obelia geniculata , Dynamena pumila , Sertularia argentea , S. operculata and S. cupressina .
Distribution:
Many of the older records were made before it was understood that D. coronata was then an aggregate species. Certainly, it has been reliably reported from Scandinavia, the Faeroes and Iceland to Spitzbergen and Murmansk, from the Mediterranean Sea (to Naples and the Aegean) and from northern Spain and Portugal, to 180 m (Distr. D. coronata).