Tyrinna evelinae
(Marcus, 1958)

Order: NUDIBRANCHIA
Suborder: DORIDINA
Superfamily: EUDORIDOIDEA
Family: Chromodorididae

DISTRIBUTION

Tropical Atlantic [Brazil to Caribbean, West Africa]; East Pacific from Mexico to Peru.

PHOTO

9mm long. Playa Mismaloya, Bahia de Banderas, Pacific Coast of Mexico at 17 feet of depth under a rock on April 22nd, 2002. Photo: Alicia Hermosillo.

The translucent white mantle is covered with orange-red spots. In some animals the spots are of similar size all over, while in others the spots around the margin are much larger than those in the central region. There is a band of small mantle glands around the edge and an inner band of larger glands. The glands are hidden by the orange spots. The species was moved from Cadlina to Tyrinna on anatomical grounds (Rudman, 1984).

The main difference between T. evelinae and the similarly coloured T. nobilis would appear to be that in T. nobilis the orange spots are absent from the central region of the mantle between the gills and the rhinophores. Their goegraphic distributions also seem to be mutually exclusive, with T. nobilis being found in the cold waters of the southern part of Sth America, while T. evelinae replaces it in the warmer north from Mexico to Peru on the Pacific coast, and from the Caribbean to sthn Brazil on the Atlantic coast. It has also been reported from west Africa.

A possible third species of Tyrinna, Cadlina burnayi Ortea, 1988 was shown (Valdés & Afonso, 2003) to be a synonym of T. evelinae.

• Marcus, Er. (1958) On western Atlantic opisthobranchiate gastropods. American Museum Novitates, 1906: 1-82.
• Muniain, C., A. Valdés, et al. (1996). Redescription of Tyrinna nobilis Bergh,1898 (Opisthobranchia: Chromodorididae) from Patagonia, Argentina. Journal of Molluscan Studies 62: 265-273.
• Rudman, W.B. (1984) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: a review of the genera. Zoological Journal of the Linnean Society, 81: 115-273.
• Schroedl, M. and S. V. Millen (2001). Revision of the nudibranch gastropod genus Tyrinna Bergh, 1898 (Doridoidea: Chromodorididae). Journal of Natural History 35(8): 1143-1171.
• Thompson, T.E. (1980) Jamaican Opisthobranch Molluscs II. Journal of Molluscan Studies, 46: 74-99
• Valdés, A. and C. M. L. Afonso (2003). Synonymy of Cadlina burnayi Ortea, 1988, from the Cape Verde Islands (Opisthobranchia: Chromodorididae) with Tyrinna evelinae (Marcus, 1958). The Veliger 46(2): 176-179.

Authorship details
Rudman, W.B., 2009 (November 18) Tyrinna evelinae (Marcus, 1958). [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/tyrievel

Copyright © Australian Museum, 1998-2010