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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 to warm temperate Indo-west Pacific Maximal size : 75 mm Abundance : (Run) Frequently on the rocky coast and the reef flat zone. (May) Frequently on the reef flat zone Species characteristics : The color ranges from orange or pink in juveniles to black or dark brown in adults. Black adults often have clusters of white spots on the mantle, and sometimes there can be a marginal or submarginal red or pink mantle border.     The relatively numerous black gills (10 or more) form an incomplete circle around the anus when extended and cup inwards. They are at the extreme posterior end of the dorsum     The rhinophores have a translucent grey stalk, black clavus and a white tip.
	Showing species characteristics...	Photo Philibert Bidgrain Réunion, Etang salé on the rocky coast, less 1 m, 30 january 2006, size : 25 mm

See more about : Sightening and mating periods
   See more about : Dendrodoris nigra variability in Southwest Indian ocean
   See more about : She try to take off : Dendrodoris nigra

Remarks :

Identification confirmed by Bill Rudman and Nathalie Yonow
    Several specimens observed in our island have a caracteristic undulating margin with blue marginal mantle border
    Synonymous (according worms) :
          - Actinocyclus australis Angas, 1864                                      - Doris atroviridis Kelaart, 1858
          - Dendrodoris australiensis (Abraham, 1877)                          - Doris debilis Pease, 1871
          - Dendrodoris melaena Allan, 1932                                        - Doris mariei Crosse, 1875
          - Dendrodoris montrouzieri (Crosse, 1875)                             - Doris nigra Stimpson, 1855
          - Doridopsis australiensis Abraham, 1877                               - Doris rubrilineata Pease, 1871
          - Doridopsis mollis Risbec, 1928                                             - Doris sordida Pease, 1871
          - Doridopsis nigra (Stimpson, 1855)                                        - Goniodoris montrouzieri Crosse, 1875
          - Doriopsis nigra (Stimpson, 1855)                                          - Hexabranchus nebulosus Pease, 1860
          - Doriopsis nigra Bergh, 1880, 1888, 1890, 1905

Bibliographic data :

When white spots are present they are of two different kinds. Some spots are simply pigment spots on the skin while others are small white glands producing a milky acidic secretion. Usually the glandular spots are aggregated into clusters.
    This species feeds on siliceous sponges and is most commonly found in the intertidal zone ( generally found at the reef crest under dead coral slabs ), it is one of the most common intertidal nudibranchs in all tropical oceans. In coastal northern Queensland, the food has been identified as Tedania aff. ignis (family Tedaniidae).
    External differences between between the two similar species : D. nigra and D. fumata :
               - D. nigra is more elongate when crawling than D. fumata
               - In D. nigra the gills are relatively numerous (10 or more short gills which stand quite upright) and form a compact circle around the anus at the extreme posterior end of the dorsum . In D. fumata there are only 5 or 6 spreading gills which are relatively large, which often spread from one side of the mantle to the other, and attached further forward.
    One internal character clearly separates the two species :
               - In D. nigra there is an accessory gland at the genital opening which is absent in D. fumata.
    Rachel Przeslawski observation : D. nigra and D. fumata laid in the laboratory a thin upright spiral orange egg ribbons with some differences :

D. nigra	looser "messier" spiral mass	egg ribbon (5.5-6 mm)	high density of embryos very tightly packed	eggs and capsules (125 µm, 175 µm)	there was only 1 egg per capsule with occasional twins
D. fumata	neatly coiled mass	egg ribbon (3-5 mm)	only had 2 layers of embryos in moderate density	eggs and capsules (75 µm, 100 µm)

Material examined by Nathalie Yonow ( see reference/publications).

One specimen collected from Grand Baie (Mauritius), 2 November 1985, size :70 mm. And five from Tamarin (Mauritius), 8 and 11 October 1985, size : 15 to 45 mm

References :

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

Publications :

Brodie G.D., Willan R.C. & Collins J.D. (1997) Taxonomy and occurrence of Dendrodoris nigra and Dendrodoris fumata (Nudibranchia: Dendrodorididae) in the Indo-West Pacific region. Journal of Molluscan Studies 63: 407-423.
    Stimpson, W. (1855). Descriptions of some of the new marine Invertebrata from the Japanese and Chinese Seas . Proceedings of the Academy of Natural Sciences of Philadelphia , 7(10) : 375-384
    Yonow, N. and Hayward , P. J. (1991). Opistobranches de l'île Maurice, avec la description de deux espèces nouvelles (Mollusca : Opistobranchia) Revue française d'aquariologie herpétologie, 18 (1), 1-30

Other photos of Dendrodoris nigra :

Seb Vasquez Réunion, Etang salé on the rocky coast, less 1 m, 20 March 2015, During the night The yellow spawn...

Philibert Bidgrain Réunion, Etang salé on the rocky coast, less 1 m, 28 february 2006 , size : 30 mm Some spots are small white glands producing a milky acidic secretion The gills are relatively numerous, cup inwards and form a compact circle around the anus at the extreme posterior end of the dorsum Severals specimens observed in our island have a caracteristic undulating margin with blue marginal mantle border

Philibert Bidgrain Réunion, Saint Pierre harbour, 1 m, under a rock, 8 december 2006, size : 35 mm When white spots are present they are of two different kinds. Some spots are simply pigment spots on the skin while others are small white glands producing a milky acidic secretion. Usually the glandular spots are aggregated into clusters.

Philibert Bidgrain Réunion, Etang salé lagoon, less 1 m, 14 January 2007, size : 20-25 mm. A "survivor", with beautiful scars Black coloration without white spots.

Maurice Jay Réunion, A specimen with a high density of white spots and a large undulating margin.

Hugues Flodrops Réunion, Etang-Salé, on the rocky coast, 2m, 28 November 2007during the night, size 45-50 mm. An albinos form. According Bill Rudman " For some reason the pigment is absent in this animal and the yellowish colour is from the viscera showing through the body wall and mantle"

Eva Fontaine mboueanatsa, Mayotte, on the reef flat zone, less 1 m, 21 October 2008, size : 20-25 mm Black adults have sometimes a marginal or submarginal red or pink mantle border.

Eva Fontaine Réunion, La saline lagoon, less 1 m, under a rock, 15 November 2009, size : 5 mm The color ranges from orange or pink in juveniles The rhinophores have a white tip. They gills are at the extreme posterior end of the dorsum

Philibert Bidgrain Réunion, La saline lagoon, less 1 m, 27 January 2010, size : 20 mm. A very dark form... A lot of observations of this species on January....5 to 7 specimens by day...

Christophe Cadet Réunion, Saint-Leu lagoon, less 1 m, January 2010, size : 4 mm A juvenile with a marginal or submarginal red or pink mantle border. And some white dots on the mantle...

Christophe Cadet Réunion, Etang salé, on the rocky coast, less 1 m, 8 September 2010, size : 20 mm A strange specimen with a transparent body wall.

Philibert Bidgrain Réunion, Etang-Salé, on the rocky coast, less 1m, 28 February 2011, size : 30 mm. The rhinophores have a translucent grey stalk, black clavus and a white tip.

Philibert Bidgrain Mboueanatsa, Mayotte, on the reef flat zone, less 1 m, 11 Jully 2010, size : 20-25 mm Large cluster of white spot are on tubercle (a)...

See more about : Dendrodoris nigra variability in Southwest Indian ocean
   Reunion, retracted gills in Dendrodoris nigra, at Saint Leu, by Philibert Bidgrain
   Reunion, pale form of Dendrodoris nigra, at Etang salé, by Philibert Bidgrain 
   Mayotte, dark form of Dendrodoris nigra, at Passe en S, by Marina Poddubetskaia 
   Mayotte, Dendronoris nigra with blue marginal mantle border, at Sakouli, by Philibert Bidgrain
   Mayotte, five specimens of Dendronoris nigra, at Sakouli, by Philibert Bidgrain 
   Mauritius, drawing of a specimen of Dendrodoris nigra, from Tamarin, by Nathalie Yonow  
   Mayotte, Dendrodoris nigra with clusters of white spots, at Moutsoumbatsou, by Matthias Deuss  
   Reunion, 5 Dendrodoris nigra with Dolabrifera, at Etang salé, by Christophe Cadet
   Reunion, Dendrodoris nigra with clusters of white spots, at Saint Gilles, by Eva Fontaine  
   Reunion, juvenile of Dendrodoris nigra with red submarginal band, at La Saline, by Philibert Bidgrain
   Reunion, orange juvenile with white dots of Dendrodoris nigra, at Etang salé, by Christophe Cadet
   Mauritius, Dendrodoris nigra with white dots, at Flic en Flac, by Philibert Bidgrain
   Réunion, "albinos form" of Dendrodoris nigra, at Etang salé, by Christophe Cadet
   Mayotte, Dendrodoris nigra with a red submarginal band, at Petite terre, by Matthias Deuss
   Seychelles, Dendrodoris noigra with clusters of white dots, at Mahé, by Christophe Mason-Parker
   Madagascar, Dendrodoris nigra, at Nosy bé, by Philibert Bidgrain
   Mayotte, Dendrodoris nigra with probably its spawn, at N'Gouja, by Philibert Bidgrain