Hypselodoris sp. 09  Genus: Stimpson, 1855

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This is an unidentified or undescribed species of the genus Hypselodoris. I call it Hypselodoris sp. 09, to distinguish it from other species of Hypselodoris.
Hypselodoris sp. 09 has a purple border to the foot and the mantle. There is a diffuse reticulate pattern of violet patches on the dorsum. It has irregular patches of bright orange on the dorsum and on the foot. The rhinophores are purple, the gills are of the same colour.
It is Risbecia sp. 2 in IPN at page 272:
Gosliner, Terrence M., David W. Behrens & Ángel Valdés. 2008. Indo-Pacific Nudibranchs and Sea Slugs. Sea Challengers Natural History Books.
Gig Harbor, Washington. 426pp.
Very similar is Hypselodoris pulchella which is known from the Indian Ocean from South Africa to Thailand and differs by its rounded yellowish-orange spots of varying sizes.
I am not convinced that Hypselodoris sp. 09 is a distinct species, I guess so is Dr. Alicia Hermosillo, she labels this shot Risbecia pulchella, this shot Risbecia sp. 1 and this shot Risbecia sp. 2.
I will keep it seperate until the dust settles.
It was posted on 14 Apr. 2011 at these websites as Risbecia sp. A  Genus: Odhner, 1934,
I changed it on 02 Jan. 2012 into Risbecia sp. 01  Genus: Odhner, 1934,
for some genera, such as Trinchesia was the alphabet almost through. I had to change the distinguishing alphabetic character into a number. I have chosen 2-digit numbers, even if '01' looks a little bit stupid, and now is only the genus italic written.
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 sp. 01 to the genus Hypselodoris  Stimpson, 1855.
How to cite:
Köhler, E. (2016), published 2 June 2016, Hypselodoris sp. 09  Genus: Stimpson, 1855
available from http://www.Philippine-Sea-Slugs.com/Nudibranchia/Euctenidiacea/Hypselodoris_sp_09.htm