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This species has been observed on Reunion and Madagascar Islands

Order : Cephalaspidea Superfamily : Philinoidea Family : Philinidae Distribution : Widespread Indo-West Pacific species Maximal size : 4 mm Abundance : Species characteristics : The body is opaque white to cream and conspicuously marked with transverse patches of dark brown varying in their width. One on the head shield and two on the posterior shield The extreme tip of the head shield always bears a black spot
	Showing species characteristics...	Photo Christophe Cadet Reunion, Etang salé lagoon, less 1 m, 23 January 2011, size : 3 mm

See more about : Sightening and mating periods

Remarks :

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

Bibliographic data :

The short head shield has a rounded margin. The posterior shield is longer than the head shield and the rear end is elaborated folded. The flaps araising from the side of the foot are small
    This is a commun inhabitant of rocky reefs and coral rubble areas from intertidal zone to 20 m depth
    This is one of the smallest species of Philine, and one of the few which is not a translucent white colour
    The resemblance of its characteristic colour pattern of black patches on a white background, to the colours of the killer whale Orca, are the reason for its scientific name.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Philine orca
   Nudipixel Philine orca

Publications :

Gosliner, T.M., (1988). The Philinacea (Mollusca: Gastropoda: Opisthobranchia) of Aldabra Atoll, with descriptions of five new species and a new genus. Bulletin of the Biological Society of Washington, 8 : 79-100, Figs 1-14.

Other photos of Philine orca :

Specimen with 3 thick (a) dark brown bands on the dorsum and one dark brown patche (b) on the external side of the parapodia	Specimen with 3 thin dark (a) brown bands on the dorsum and without (b) a dark brown patche on the external side of the parapodia
Reunion, Etang salé lagoon, less 1 m, 23 January 2011, size : 3 mm	Reunion, Etang salé lagoon, less 1 m, 14 November 2011, size : 3-4 mm

Chritophe Cadet Reunion, Etang salé lagoon, less 1 m, 14 November 2011, size : 3-4 mm About 10 specimens with two commun pattern (the first one with thick dark brown bands and the second one with thin dark brown bands )

Alexandre Laporte Madagascar, Sainte Marie, La Crique Lagoon, less 1 m, 2 September 2017, size : 2-3 mm