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

Order : Sacoglossa Superfamily : Plakobranchoidea Family : Plakobranchidae Distribution : ndo-West Pacific. Maximal size : 50 mm Abundance : From time to time on the reef flat zone and seldom on the rocky coast Species characteristics : The animal is usually a translucent green colour with a black parapodial margin and a submarginal yellow or orange band.    The tip of the rhinophores often have the same colour bands    There are also numerous black and white dots all over the body
	Showing species characteristics...	Photo Alain Barrére Reunion, Saint Pierre lagoon, floating on the water at 8 p.m, 01 June 2005, size :15-17 mm

See more about : Sightening and mating periods
   See more about : Elysia marginata variability in Southwest Indian ocean

Remarks :

Identification confirmed by Kathe Jensen, Bill Rudman and Hsini Lin
    According Krug P.J., Vendetti J.E. & Valdés Á. (2016) :
            - Both E. marginata and E. grandifolia were synonymized with E. ornata based on morphological comparisons between Pacific and Caribbean material (Ev. Marcus 1980; Heller & Thompson 1983; Jensen 1992). Recent integrative taxonomic work revealed that the E. marginata-grandifolia complex contained four candidate species in Pacific, all distinct from each other and from E. ornata by (1) molecular sequence analyses of two genetic loci; (2) external features including color of rhinophores and marginal bands, folding of parapodia into siphonal openings, tail shape, and pattern of dorsal vessels; and (3) color and pattern of ECY (Krug et al. 2013). Elysia ornata is therefore restricted to the Caribbean, and some related Pacific species await formal description
            - These two species of Elysia feeding on Bryopsis spp. were described from the tropical Pacific. Both have a black band along the parapodial edge and a submarginal orange band similar to those of E. ornata . The first species, E. grandifolia (Kelaart, 1858), was described from Sri Lanka as having black and gold marginal lines along parapodia that fused with the tail (Kelaart 1858). The second species, E. marginata (Pease, 1871) was originally described from the Hawaiian Islands and subsequently from Tahiti as having a white band between the orange and black marginal bands (Pease 1871) .
    There is in many specimens a white band well visible, so it's probably Elysia marginata
    Synonymes (d'après worms) :
               - Pterogasteron marginatus Pease, 1871

Bibliographic data :

The animal is usually a translucent green colour with a black parapodial margin and a submarginal yellow or orange band. Sometimes there is a white line between the orange and black bands
    Jensen (1992) reports that E. ornata feeds on Bryopsis in both the Caribbean and the Indo West Pacific. The Sacoglossans are unique in their very specialised feeding mechanism, they pierce a hole in the algae and suck out the cell contents.
    Typical for this genus, the rudimentary eyes are located behind the rhinophores.

References :

Philippines Seaslug : Elysia ornata
   Seaslug of Hawai Elysia ornata

Publications :

Krug P.J., Vendetti J.E. & Valdés Á. (2016). Molecular and morphological systematics of Elysia Risso, 1818 (Heterobranchia: Sacoglossa) from the Caribbean region. Zootaxa. 4148(1): 1-137.

Other photos of Elysia marginata :

Eva Fontaine Mayotte, Mtsanga Tanaraki, less 1 m, 25 Jully 2011, size : 15 mm Some specimens from Mayotte Island have some constant pattern variations : - Presence of a white line (a) between the orange and black bands - Presence of large diffuse white patches (b) just under the marginals band - Absence of small white dots on the body wall, just only black spots... We need other photo from Mayotte to confirm this observation

Philibert Bidgrain Found in a pool at "Kélonia center" a Marine Turtle Center in Saint Leu. Réunion, 20 March 2010, size : 20-25 mm A specimen with a coloration pattern very clear. The parapodial margin is bright yellow and black

Philibert Bidgrain Reunion, Etang salé les bains, on the rocky coast 17 October 2005, size : 20mm

Philibert Bidgrain Reunion, Etang salé lagoon, under a rock, less 1 m, 3 February 2007, size 15-18 mm

Fabrice Schubert Mayotte, Mliha, 3m, 17 January 2010, size : 30 mm The animal is usually a translucent green colour with a black parapodial margin and a submarginal orange band. In this specimen there is a white line (a) between the orange and black bands Specimen with very few white spots on the parapodia

Philibert Bidgrain Reunion, Trou d'eau lagoon, less 1 m, 2 July 2010, size 8 mm An anormal or partially eaten specimen with only a partial parapodia

Stéphane Ciccione Found in a pool at "Kélonia center" a Marine Turtle Center in Saint Leu. Réunion, 23 August 2010, size : 45 mm Pericardium (a) and blood dorsal vessels (b).

Philibert Bidgrain Mayotte, mtsanga M'titi Sada , less 1 m, 17 July 2010, size 15 mm

Christophe Mason-Parker Seychelles, baie Ternay, Mahé, 1 m, 14 November 2010 The animal is mottle green colour with a black parapodial margin and a faint submarginal yellow/orange band on parapodial margin and rhinophores

Pierre Conchylinet Mauritius, 20 m Presence of a white line (a) between the orange and black bands Presence of a large dark green area (b) near the marginal bands

Alain-Benoît rassat Madagascar, Patate de l'entrée, Nosy Bé, 8 m, 13 April 2016, size : 60 mm

See more about : Elysia marginata variability in Southwest Indian ocean

Reunion, three Elysia species in the same area, at Etang salé, by Philibert Bidgrain

Reunion, friendly meeting between two Elysia species, at Etang salé, by Philibert Bidgrain

Reunion, Elysia marginata , at Saint Paul, by Alain Diringer

Reunion, Elysia marginata , at Trou d'eau, by Philibert Bidgrain

Mauritius, dark green Elysia marginata , at Mahebourg, by Yann von Arnim