Lomanotus marmoratus

(Alder & Hancock, 1845)

The body length reaches 39 mm. The cerata of the juveniles are simple tubercles, but in the adult they are positioned along the edge of the enlarged, sinuous pallial rim. The cerata are more slender and elongated than those of Lomanotus genei , and, moreover, exhibit a typical sub-terminal swelling. They never possess gill-like wrinkles, nor do they curve. The colour pattern is drab and consists of superficial speckles of chalk-white and dark brown, giving rise to a mottled effect. The brown digestive gland is visible through the skin.

This rare species is usually found on the hydroid Nemertesia antennina in shallow subtidal localities.

Most records have been from the south western parts of England and Ireland (although there are some reports from the North Sea, on the English coast; Distr. L. marmoratus).