Hypselodoris tryoni (Garrett, 1873) [Goniodoris]

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Hypselodoris tryoni is characterized by a high shape of the body with a reduced mantle overlap. There is a group of similarly coloured species which Bill Rudman called the "Hypselodoris tryoni colour group". They all have large purple or purple-brown spots or marks, usually ringed with white, an often reticulate brownish background, and a purple border:
Chromodoris geminus which has four colour bands around the mantle edge: an outermost white, then translucent greyish purple, then white, then yellow. It has a wide mantle overlap.
Goniobranchus kuniei which has a broad purple line at the border of the mantle and a wide mantle overlap.
Goniobranchus leopardus which has leopard-like multiple spots, or marks, forming a hollow squarea, distinct purple line at the border of the mantle and a wide mantle overlap.
It was posted on 25 July 2003 at these websites as Risbecia tryoni (Garrett, 1873) [Goniodoris],
I follow the recent article (published: 10 April 2012)
Rebecca Fay Johnson & Terrence M. Gosliner. 2012.
Traditional Taxonomic Groupings Mask Evolutionary History:
A Molecular Phylogeny and New Classification of the Chromodorid Nudibranchs. online at
and move Risbecia tryoni to the genus Hypselodoris  Stimpson, 1855.
More information on Hypselodoris tryoni as Risbecia tryoni are on Bill Rudman's Sea-Slug Forum!