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

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Phyllidioidea Family : Dendrodorididae Distribution :Tropical Indo-West Pacific. Maximal size : 400 mm Abundance : Seldom on the reef flat zone and on the fore reef zone Species characteristics : Large individual tubercules separated by smooth sections of the mantle. Each large tubercle is surrounded by a ring of small semispherical bumps
	Showing species characteristics...	Photo Maurice Jay Réunion, "Cap Homard" lagoon at Saint Paul, at night.

Large individual tubercules separated by smooth sections of the mantle. Each large tubercle is surrounded by a ring of small semispherical bumps	The underside of the mantle is a uniform brown or reddish brown, sometimes with darker diffuse patches

See more about : Sightening and mating periods
   See more about : From juvenile to adult at Dendrodoris carbunculosa

Remarks :

Identification confirmed by Bill Rudman and Nathalie Yonow
    Synonymous : (according Worms)
          - Doris carbunculosa kelaart, 1858

Bibliographic data :

The flattened compound tubercles are rather characteristic of this species.
    Ian Loch reports that the mucous secretions of an animal he collected in Townsville caused painful burning sensations to his lips and eyes presumably via his hands.
    A black or dark brown background colour on the mantle is often found in D. carbunculosa but never in D. tuberculosa ( if you find this colour form in Reunion Island, please Contact us...)
    Found under stones during the day and crawling over swallow reefs at night.
    As with most members of the family dendrodorididae, they prefer the intertidal area. Mud flats and muddy reefs are preferred by this seaslug.
    D. carbunculosa appears to be closest to D. tuberculosa but :

D. tuberculosa	D. carbunculosa
The whole of the mantle is covered with tubercles. Usually these are simple rounded cones but scattered amongst them are large compound tubercles with conical tubercles. The underside of the mantle, has a background colour ranging from pale greenish or yellowish brown to dark brown with large round white spots.	Large individual tubercules separated by smooth sections of the mantle. Each large tubercle is surrounded by a ring of small semispherical bumps The underside of the mantle is a uniform brown or reddish brown, sometimes with darker diffuse patches
Both species have quite stiff bodies with fairly leathery mantles.

Juvenile form have a black line between the foot and mantle and the dorsum is black with whitish tubercles.
    Earlier workers, (Eliot, Alder & Hancock, Bergh) considered that Kelaart's species was probably just a variety of Dendrodoris tuberculosa (Quoy & Gaimard, 1832), differing only in the colour of the underside of the mantle.
Bill Rudman says that It is possible that these two species are opposite extremes of a range of variation, but he has neither seen nor read of the existence of any intermediate forms., so...

References :

Bill Rudman Seaslug site : Sea Slug Forum : Dendrodoris carbunculosa
   Nudipixel Dendrodoris carbunculosa

Publications :

Alder J. & Hancock A. (1864). Notice of a collection of nudibranchiate Mollusca made in India by Walter Elliot Esq. with descriptions of several new genera and species. Transactions of the Zoological Society of London 5 (3-4): 113-147
page(s): 128
    Kelaart, E.F. (1858). Description of new and little known species of Ceylon nudibranchiate molluscs and zoophytes. Journal of the Ceylon Branch of the Royal Asiatic Society, Columbo, 3(1) : 84-139.
    Yonow, N. Anderson, C. and Buttress, S. G. (2002). Opistobranch molluscs from the Chagos Archipelado, Central Indian Ocean. Journal of Natural History, 36, 831-882

Other photos of Dendrodoris carbunculosa :

Kelaart's painting Kelaart's unpublished paintings in the Natural History Museum, London, of "Doris carbunculosa" from Ceylon. The grey inset is an enlargement to show the nature of the tubercles.

Yvon Gildas Mayotte, Passe en S - buoy n°3, 6m, 12 September 2009      Large individual tubercules (a) separated by smooth sections of the mantle. Each large tubercle is surrounded by a ring of small semispherical bumps (b)

Christophe Cadet Réunion, Etang salé on the rocky coast, less 1 m, 13 March 2010, size : 140 mm In this specimen the large individual tubercules (a) are multi-coumpound . Each large tubercle is surrounded by a ring of small semispherical bumps (b)

Philibert Bidgrain Réunion, Etang Salé on the rocky coast, less 1 m, 13-15 December 2006, size : 25 mm   A juvenile form The mantle is soft, and a black line (a) runs between the foot and the mantle. The dorsum is dark with whitish tubercles. The large five (or six?) compound gills which form a circle around the anus emerge from a deeply lobed branchial pocket.

Nathalie Rodrigues Réunion, Cap la Houssaye, on the rocky coast, 30 May 2014 An intermediate form between juvenile and adult The mantle colour is black surrounding large tubercles. These have a white base and are capped with orange brown.

Sonia Ribes Beaudemoulin Réunion, "Pointe au sel" lagoon at Saint Leu, under a dead coral, 5 m from the beach, 19 January 2008, size : 60-70 mm  The underside of the mantle is a uniform brown or reddish brown

Christophe Cadet Reunion, Etang salé, on the rocky coast, less 1 m, 26 December 2010, size : 90 mm During the night

Seb Vasquez Réunion, Etang Salé on the rocky coast, less 1 m, 23 March 2015 During the night Two specimens with different gills coloration... Deux individus différents au niveau de la coloration de leurs branchies ..

See more about : From juvenile to adult at Dendrodoris carbunculosa

Reunion, Dendrodoris carbunculosa, at Saint Leu, by Sebastien Pomarade

Mauritius, Dendrodoris carbunculosa with multi-coumpound large tubercles, at Riviére noire, by Hilary Jones  

Madagascar, Dendrodoris carbunculosa, at Nosy Bé, by Alain-Benoît Rassat