Thuridilla virgata (Bergh, 1888)

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


Order : Sacoglossa
Superfamily : Plakobranchoidea
Family : Plakobranchidae
Distribution : Known only from the Indian Ocean; Mauritius, Madagascar, South Africa, Tanzania and now Réunion island
Maximal size : 25 mm
Abundance : From time to time on the fore reef zone and the reef flat zone


Species characteristics :

The body is a pale bluish white with a series of broad black longitudinal bands, of irregular width and length, on the parapodia
    The rhinophores, or at least the upper two-thirds, are golden yellow to orange

Thuridilla virgata
Showing species characteristics...

Photo Emmanuel Eby
Reunion, Saint Leu, 02 October 2005, size 15-20 mm

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

Remarks :

Identification confirmed by Bill Rudman
    Synonymous : (according Worms)
               - Elysia virgata (Bergh, 1888)                        - Plakobranchus virgata Bergh, 1888

Bibliographic data :

The head is essentially black with a Y-shaped bluish white band running along the medio-dorsal line, a branch going to each rhinophore.
    The parapodial margin is the same colour as the remainder of the body
    The anterior margin of the foot are black
    Usualy found on shallow reefs

References :

Bill Rudman Seaslug site : Sea Slug Forum : Thuridilla virgata

Publications :

Bergh, L.S.R. (1888) Malacologische Untersuchungen. In: C.G. Semper, Reisen im Archipel der Philippinen, Wissenschaftliche Resultate. Band 2, Heft 16a : 755-814. (Pls. 77-81)
    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 Californian Academy of Sciences 49(1) : 1-54.
    Jensen, K.R. (2007). Biogeography of the Sacoglossa (Mollusca, Opisthobranchia). Bonner Zoologische Beiträge. 55: 255281.

Other photos of Thuridilla virgata :


Emmanuel Eby

In this dorsal view, you can see the Y-shaped bluish white band running along the medio-dorsal line, a branch going to each rhinophore.

Reunion, Saint Leu, 02 October 2005, 15-20 mm

 

thuridilla virgata


Sophie Darnis

Reunion, "Petit Moteur" at Saint-Gilles, 29 December 2007, 5 m, size 12-15 mm

A series of broad black longitudinal bands, of irregular width and length, on the parapodia

The posterior right parapodia seems to be eaten...


Hugues Flodrops

Reunion, "Piscine de Grande Anse, " 25 December 2007 during the night, less 1 m, size 25 mm


Eva Fontaine

Photo opposite :
mtsanga Mbouéanatsa at Mayotte, on the reef flat zone, less 1 m,
2 August 2008, size : 10-12 mm.

 

Photo below :
mtsanga Guini at Mayotte, on the reef flat zone, less 1 m,
27 July 2008, size : 5-7 mm

A juvénile form with a deep blue coloration....


Eva Fontaine

Mayotte, Chissioua Sada, on the reef flat zone, less 1 m, 16 October 2008, size : 10-12 mm

A specimen with a deep blue coloration


Alain-Benoît rassat

Madagascar, Nosy bé, Licorne, 17 m, 6 April 2015, size : 16 mm

A specimen with an intense blue coloration and a light pinkish coloration on the edge of the parapodia


 More photos from Indian Ocean

See more about : Thuridilla phylogeny by Gosliner 1995

See more about : Thuridilla vatae variability in Southwest Indian ocean

Mauritius, Thuridilla virgata, at Pereybere , by Marina Poddubetskaia

Mauritius, another Thuridilla virgata, at Pereybere, by Marina Poddubetskaia

Reunion, Thuridilla virgata with broken longitudinal black bands, at Trou d'eau, by Philibert Bidgrain  

Madagascar, Thuridilla virgata, at Nosy Bé, by Alain-Benoît Rassat