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This species has been observed on Reunion, Mauritius, Mayotte, Madagascar and Seychelles Islands

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Doridoidea Family : Chromodorididae Distribution : Indian Ocean Maximal size : 50 mm Abundance : Seldom on the fore reef zone Species characteristics : It has dark blackish lines, usually diagonal, and yellowish patches between. The rhinophores are orange red and the gills are edged with the same colour The background colour of the body has a bluish or purplish tinge.
	Showing species characteristics...	Photo Fabrice Bettex Mauritius, Trou aux Biches, 20 m, 26 April 2006, size 20 mm

See more about : Sightening and mating periods

Remarks :

Synonymous : (according Worms)
          - Chromodoris nigrostriata, Eliot, 1904

Bibliographic data :

The purple and black lines covered the dorsal surface and sides of the foot, but did not include the mantle edge, which was plain yellow.
    Foot with pale purple marginal band
    The sole of the foot and the head and tentacles are light purple in colour.
    There are nine gills, triangular in cross-section, the pinnules or lamellae being on the inner two sides. The three edges of each gill are bright orange, the two lamellate sides are white and the smooth outer side is whitish orange. They form a complete circlet
    The yellow around the edges is a brighter colour than the other yellow markings arranged in a fairly regular pattern over the dorsum
    The mantle shape is spatula-shaped, there is only a small mantle overlap, except at the head end, and the high foot extends a considerable distance behind the end of the mantle.
    H. nigrostriata appears to eat dysideid sponge
    Other species with dark blackish lines include Hypselodoris nigrolineata, Hypselodoris maritima, Hypselodoris kanga and Hypselodoris zephyra.
    Specimen from the western Indian Ocean has much more prominent yellow markings than specimens found from further east areas.

Hypselodoris nigrostriata is rather similar in colour to the Western and Central Pacific species Hypselodoris zephyra . But for some authors, they are the same species.

H. nigrostriata is one of a group of species of Hypselodoris in which the body resembles a Nembrotha, with a narrowing of the mantle skirt and a heightening of the body. But Nembrotha feeds on ascidians and Hypselodoris feeds on sponge...

References :

Bill Rudman Seaslug site : Sea Slug Forum : Hypselodoris nigrostriata
   Nudipixel Hypselodoris nigrostriata

Publications :

Eliot, C. N. E., 1904, On some nudibranchs from east Africa and Zanzibar . Part IV , Proceedings of the Zoological Society , London , 1, 380-406.
    Gosliner, T.M. & Johnson, R.F. (1999) Phylogeny of Hypselodoris (Nudibranchia: Chromodorididae) with a review of the monophyletic clade of Indo-Pacific species, including descriptions of twelve new species. Zoological Journal of the Linnean Society, 125 : 1-114.
    Johnson R.F. & Gosliner T.M. (2012) Traditional taxonomic groupings mask evolutionary history: A molecular phylogeny and new classification of the chromodorid nudibranchs. PLoS ONE 7(4): e33479
    Rudman, W.B. (1977) Chromodorid opisthobranch Mollusca from East Africa and the tropical West Pacific. Zoological Journal of the Linnean Society 61 : 351-397.

Other photos of Hypselodoris nigrostriata :

Alain Benoît Rassat Madagascar,Nosy bé,

Sophie Darnis Réunion, "Roches Cernica" at Saint Gilles, 10 November 2007, 32m, size : 25 mm This specimen looks like Fabrice Bettex Mauritius specimen. It has exactly the same coloration pattern The black lines on the body are diagonal. There is a yellow marginal band The rhinophores are orange red The gills seems to be uniformly translucent orange

Fabrice Schubert Mayotte, Bandrele, 8 m, 10 January 2010, size : a few specimen between 30 and 60 mm A specimen with its spawn??? Strange gills coloration with white patches along the outer face. It looks like H. zephyra, but other characters corresponded to H. nigrostriata description

Emmanuelle Aigle Mayotte, Bandrele, 5 m, 19 November 2010 Always a strange gills coloration for this specimen....

Philibert Bidgrain Mayotte, N'gouja, less 1 m, 14 November 2011, size : 15 mm Small specimen from Mayotte without white patches along the outer face of the gills

Alain-Benoît Rassat Madagascar, Nosy Bé, banc du corail noir, 29 m, 29 March 2014, size : 30 mm A decolorated specimen...

Alain-Benoît Rassat Madagascar, Nosy Bé,

Reunion, lateral view of Hypselodoris nigrostriata, at Saint Gilles, by Sophie Darnis