Atlantic coast of Nth America from Nova Scotia to South Carolina.
Placobranchus catulus -from a drawing by Toppan of an East Boston specimen. Gould, 1870: PLATE XVII. Fig. 249.
Small elysiid reaching approximately 6mm in length. The body is heavily pigmented with black but the greenish tinge of the body contents can be seen on close examination. Whitish marks form a regular pattern: There is an elongate one on the head between the rhinophores, and similar ones on each side of the head running across the eyes. There are up to three white patches at the edge of the parapodia, one at the front, one midway down, and sometimes a third at the back, where the parapodia runs into the posterior tip of the foot. This species feeds on the sea grass Zostera and its name catulus [little cat] is a reference to its likeness to a small cat.
As is discussed elswhere on the Forum, Elysia serca is most probably the same species
• • Bleakney, J.S., 1996 Sea Slugs of Atlantic Canada and the Gulf of Maine. Nimbus Publishing & Nova Scotia Museum, Halifax, Nova Scotia.
• Gould, A.A. (1870). Report on the Invertebrata of Massachesetts. Wright and Potter: Boston. 524pp.
Rudman, W.B., 2004 (March 11) Elysia catulus (Gould, 1870). [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/elyscatu