Selection: Risbecia tryoni

Risbecia tryoni (Garrett, 1873) [Goniodoris]

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Risbecia tryoni is characterised 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 "Risbecia 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.
Chromodoris kuniei which has a broad purple line at the border of the mantle and a wide mantle overlap.
Chromodoris 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.
More informations on Risbecia tryoni are at Bill Rudman's Sea-Slug Forum!