Ercolania cf. coerulea from Tanzania

March 30, 2002
From: Bill Rudman

Dear Kathe,
Following your comments on Ercolania cf. coerulea, I would be interested in hearing your views on this animal which I found a couple of times on Dictyosphaeria cavernosa in Tanzania.

In the lower photo you can see how well camouflaged it is on its algal food the white marks on the bubble-shaped cerata matching the light reflected off the bubble-shaped cells of the algae. In the photo you can see the branching of the gut in the head and rhinophores. The cerata were essentially transparent except for scattered white specks which I assume are glandular, and some green streaking where thin digestive gland ducts reached out to the ceratal wall. The tip of each ceras was constricted and nipple-like, and packed with opaque white glandular granules. I have no record of blue spots.

PHOTO: Oyster Bay, Dar es Salaam, Tanzania. 25 Feb 1978 on algae Dictyosphaeria cavernosa. 8 animals, largest 12mm long alive. Photos: Bill Rudman

I also found this species at the same locality on Dictyosphaeria in July 1975. Does this fit into your concept of Ercolania coerulescens or is that species restricted to the Mediterranean - Atlantic region?
Best wishes,
Bill Rudman

Rudman, W.B., 2002 (Mar 30) Ercolania cf. coerulea from Tanzania. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6580

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