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This species has been observed on Reunion Island

Order : Sacoglossa Superfamily : Plakobranchoidea Family : Plakobranchidae Distribution : Japon, Hawai, Réunion Maximal size : 20 mm Abundance : Seldom on Codium sp Species characteristics : It is uniformly grass-green with numerous white, thread-thin papillae scattered over the body surface, especially on parapodia and rhinophores Also it has numerous tiny orange or red dots scattered over the body Its parapodia are thick and their margins touch or slightly overlap each other throughout their length except for two small gaps where the margins part. These gaps are marked with small white papillae.
	Showing species characteristics...	Photo Christophe Cadet Reunion, Etang Salé lagoon, less 1 m, 26 December 2009, size : 20 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Kathe Jensen
    Synonymous : (according Worms)
               - No other name

Bibliographic data :

The parapodia remain closed even when the animal is disturbed
    The uniform green colour of the body and parapodia results from a fine network of ducts, packed with chloroplasts, scattered throughout the body wall
    It almost perfectly mimics the appearance of its host algae and is known to feed on Codium

References :

Bill Rudman Seaslug site : Sea Slug Forum : Elysia trisinuata

Publications :

Baba, K. (1949) Opisthobranchia of Sagami Bay collected by His Majesty, the Emperor of Japan . Iwanami Shoten, Tokyo.
    Jensen, K.R. (1985) Annotated checklist of Hong Kong Ascoglossa (Mollusca: Opisthobranchia), with descriptions of four new species. In: Proceedings of the 2nd International Workshop on the Malacofauna of Hong Kong and Southern China, Hong Kong, 1983. (Eds: Morton,B; Dudgeon,D) Hong Kong University Press, Hong Kong, 77-107
    Jensen, K.R. (1992). Anatomy of some Indo-Pacific Elysiidae (Opisthobranchia: Sacoglossa [=Ascoglossa]), with a discussion of the generic division and phylogeny. Mal. Soc. London, 58 : 257-96
    Jensen, K.R. (1998) Zoogeographic affinities of Hong Kong Opisthobranchia (Mollusca, Gastropoda). In : Morton B (ed.) The Marine Biology of the South China Sea . Hong Kong University Press, Hong Kong, p 43-55
    Jensen, K.R. (2007). Biogeography of the Sacoglossa (Mollusca, Opisthobranchia). Bonner Zoologische Beiträge. 55: 255–281.

Other photos of Elysia trisinuata :

Photo Christophe Cadet Reunion, Etang Salé lagoon, less 1 m, 26 December 2009, size : 20 mm Its parapodia are thick and their margins touch or slightly overlap each other throughout their length except for two small gaps where the margins part. These gaps (a) are marked with small white papillae.

Photo Christophe Cadet Reunion, Etang Salé, on the rocky coast, less 1 m, 28 December 2010, size : 15-18 mm On its Codium sp with a small Placida sp (a)