October 20, 2001
From: Bill Rudman
PHOTOS: TOP RIGHT: West Head, Flinders, Westernport Bay, Victoria, Australia. March 1986. Shell length 4mm approx. Inset showing protoconch. LOWER RIGHT: same animal from right side. LOWER LEFT: Goat Island Bch, Ulverstone, nthn Tasmania, Australia. On Caulerpa geminata. February 1984. Animal 9mm long (shell approx 5mm).
PHOTOS: Bill Rudman.
As I recently promised, here is some information on one of the bivalved sacoglossans, Tamanovalva babai, from south-eastern Australia.
Burn (1960) originally misidentified this species as Berthelinia typica (Gatliff & Gabriel) but he corrected his error in 1965 where he renamed this species, Tamanovalva babai, and redescribed Gatliff & Gabriel's species as Edenttellina typica. In Tamanovalva, the larval shell (protoconch) is very prominently displayed on the apex of the left shell valve (see Inset in upper photo). This clearly shows the gastropod (snail) relationships of these animals. The discovery of living animals of these strange 'bivalved gastropods' by Kawaguti & Baba (1960) in Japan caused a stir in the scientifc community and a rush to Caulerpa beds worldwide to find more species. Compare this species with the other two southeastern Australian species Midorigai australis and Edenttellina typica.
• Burn, R.F. (1960) Australian bivalve gastropods. Nature, 187(4731): 44-46.
• Burn, R.F. (1965) Rediscovery and taxonomy of Edenttellina typica Gatliff and Gabriel. Nature, 206(4985): 735-736.
• Burn, R. (1989) Chapter 12. Opisthobranchs (Subclass Opisthobranchia). In: Shepherd, S.A. & Thomas, I.M. (Editors) Marine Invertebrates of Southern Australia Part 2, South Australian Government Printer, Adelaide.
Rudman, W.B., 2001 (Oct 20) Tamanovalva babai from south-eastern Australia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/5518