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This species has been observed on Reunion and Mayotte Islands

Order : Sacoglossa Superfamily : Plakobranchoidea Family : Plakobranchidae Distribution : Indo-West Pacific Maximal size : 20 mm Abundance : Seldom on the fore reef zone and the rocky coast Species characteristics : The body is dark bluish with scattered black and yellow spots The apex of the rhinophores is bright red or orange The margin of the parapodia is cream to yellow, but this pigment does not form a distinct band as in other members of the genus
	Showing species characteristics...	Photo Sophie Darnis Reunion, "Passe de l'Hermitage " at Saint Gilles, 31 December 2007, 12 m, size 10 mm

See more about : Sightening and mating periods
   See more about : Thuridilla phylogeny by Gosliner 1995
   See more about : Thuridilla vataae variability in Southwest Indian ocean

Remarks :

Identification confirmed by Bill Rudman
    Synonymous : (according Worms)
               - Elysia vataae Risbec, 1928                - Elysia vatae Risbec, 1928   

Bibliographic data :

Material examined by M. L. Gosliner ( see reference/publications).

CAZIZ 087158, one specimen, dissected, 2 km south of St Gilles, Reunion, 2m depth, 27 July 1977, M. L. Gosliner

Characteristics

The head is the same color as the body with a y-shaped yellowish or white marking that extends onto most of the length of the rhinophores
    T. vataae is quite similar in colour to T. albopustulosa but

T. vataae	T. albopustulosa
The ground color is a dark gray to black The parapodia are ornamented with black and yellow spots White pigment covers most of the length of rhinophores and only the apex is red/orange. The tip of the rhinophores is a solid transverse band of red pigment	The ground color is blue The parapodia are white or cream The majority of the rhinophores are red/orange rather than white The tip of the rhinophores is a transverse band with median white patches or line.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Thuridilla vatae
   Nudipixel Thuridilla vataae

Publications :

  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.
    Gosliner, T.M. (1995) The genus Thuridilla (Opisthobranchia: Elysiidae) from the tropical Indo-Pacific, with a revision of the phylogeny and systematics of the Elysiidae. Proceedings of the California Academy of Sciences, 49(1) : 1-54.
    Jensen, K.R. (2007). Biogeography of the Sacoglossa (Mollusca, Opisthobranchia). Bonner Zoologische Beiträge. 55: 255–281.

Other photos of Thuridilla vataae :

Philibert Bidgrain Reunion, La Saline lagoon, less 1 m, 28 June 2010, size : 10-12 mm A specimen with its spawn...

Christophe Cadet Reunion, La Saline lagoon, less 1 m , 30 December 2009, size : 13 mm In this specimen the margin of the parapodia is yellow. but this pigment does not form a distinct band as in other members of the genus

Hugues Flodrops Reunion, "Pool of Grande Anse", 25 December 2007, 1 m, size : 20 mm. Crawling on algae during the night This specimen present an important orange coloration on the rhinophore

Philibert Bidgrain Reunion, Trou d'eau lagoon, less 1 m, 17 June 2010, size : 10 mm In this specimen the margin of the parapodia is cream. but this pigment does not form a distinct band as in other members of the genus

Maurice Jay Reunion, The head is the same color as the body with a y-shaped yellowish or white marking that extends onto most of the length of the rhinophores

Philibert Bidgrain Mayotte, Mtsanga Tanaraki, less 1 m, 24 July 2010, size : 10 mm Two specimens with their with orange spawn

See more about : Thuridilla phylogeny by Gosliner 1995

See more about : Thuridilla vataae variability in Southwest Indian ocean

Reunion, Thuridilla vataae, at Saint Leu, by Sebastien Pomarede 

Reunion, abnormal Thuridilla vataae with two tails, at Saint Gilles, by Philibert Bidgrain  

Reunion, Thuridilla vataae with its orange spawn, at Saint Gilles, by Philibert Bidgrain