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This species has been observed on Mayotte Island

Order : Cephalaspidea Superfamily : Philinoidea Family : Gastropteridae Distribution : Japon, Western Pacific of Australia, Indonesia, New Caledonia, Papoua New Guinea and now Mayotte Maximal size : 20 mm Abundance : Species characteristics : It has two dorsal conical appendages (bicornutum) on the posterior shield and an elongate filament on the posterior end of the foot Dark brown background with numerous little white spots and large orange/yellow area
	Showing species characteristics...	Photo Emmanuelle Aigle Mayotte, Mliha, 6 m, 3 December 2009, size : 20 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow µ
    Synonymous : (according Worms)
               - No other name

Bibliographic data :

In some specimen, the animal was translucent with scattered spots of orange/yellow, brown and white. In our specimens the translucent color disappeared, all the body seems to be covered by brown pigment and white and orange/yellow spots.
    This species is found crawling on sand in relatively shallow water in 3-10 m of water

References :

Bill Rudman Seaslug site : Sea Slug Forum : Gastropteron bicornutum
   Nudipixel Gastropteron bicornutum

Publications :

Baba, K. & Tokioka, T. (1965) Two more new species of Gastropteron from Japan, with further notes on G. flavum T. & B. (Gastropoda : Opisthobranchia). Publications of the Seto Marine Biological Laboratory, 12(5) : 363-377, Text-figs 1-8, Pl.25.
    Baba, K. (1970) List of the Gastropteridae and Runcinidae from Japan. Collecting and Breeding, 32(2) : 46-48
    Gosliner, T.M. (1989) Revision of the Gastropteridae (Opisthobranchia: Cephalaspidea) with descriptions of a new genus and six new species. The Veliger, 32(4) : 333-381. (Figs 1-32)

Other photos of Gastropteron bicornutum :

Emmanuelle Aigle Mayotte, Mliha, 6 m, 3 December 2009, size : 20 mm Several specimens crawling on the sand, and some specimen "swimming"...with mouvements of the parapodia... Mating behavior on the sand...