Re: Elysia cf cornigera from Florida

December 23, 2000
From: Bill Rudman

Dear Anna,

In reference to Anna's message about the red-spotted Elysia. I have found the Nuttall reference. It's:
Nuttall, T.R. (1989) A new Elysia (Opisthobranchia: Ascoglossa) from the Florida Keys. The Veliger, 32(3): 302-307

Elysia cornigera is described as having a colourless body with bright green digestive diverticula and small brilliant red and pale orange granular spots. In the description the pale orange spots are larger than the red ones. The red spots don't seem as large as in Anna's photos. Elysia cornigera feeds on Acetabularia crenulata and in many ways is very similar to the Mediterranean Elysia timida Risso 1818 which also feeds on Acetabularia.

E. cornigera is said by Nuttall to differ from E. timida in having pointed extensions of the parapodial edge (2 each side?), a warty skin, orange spots and in having a differently shaped radular tooth

Having a look at the many photos of E. timida on Erwin Koehler's Mediterranean Slug Site, it would seem there is enough colour variation in size and number of red spots to wonder whether E. timida is amphiatlantic, with populations in both the Mediterranean and the Atlantic. In those photos you can clearly see the extensions of the parapodial edge which are supposedly exclusive to E. cornigera.
Best wishes,
Bill Rudman.
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