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

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Doridoidea Family : Chromodorididae Distribution : Throughout the tropical Indo-West Pacific Maximal size : 95 mm (usually 50 mm) Abundance : Seldom on the rocky coast Species characteristics : The mantle is opaque white with open red reticulations on the central area and flanks, and one row of dark-red reticulated spots on the outer flanks. The mantle has a narrow, golden marginal band. The lamellate rhinophores are dark red, with the lamellae either specked or edged with white.
	Showing species characteristics...	Photo Philibert Bidgrain Reunion, Etang salé, on a rocky coast, 25 October 2005, size : 40 mm

See more about : Sightening and mating periods
    See more about : Goniobranchus tinctorius variability in Southwest Indian ocean

Remarks :

Identification confirmed by Bill Rudman and Nathalie Yonow
    Synonymous (according worms) :
          - Chromodoris reticulata, (pease, 1866)
          - Chromodoris tinctoria, (Rüppell & Leuckart, 1830)
          - Doris tinctoria, Rüppell & Leuckart, 1830
          - Ceratosoma ornatum, Bergh, 1890
          - Ceratosoma rhopalicum, Rochebrune, 1894

Bibliographic data :

Extensive collections from throughout the Indo-West Pacific indicate that the species differences suggested by different colour patterns of Doris tinctoria Ruppell & Leuckart, 1828 (reticulate central region, then a white submarginal band with red spots, and a yellow margin.), Doris reticulata Quoy & Gaimard ( from animals collected in New Guinea without a yellow border), 1832, Goniobranchus reticulatus Pease, 1866 ( from Tahiti which has a yellow-orange margin as well as a distinct white submarginal border), Chromodoris alderi Collingwood, 1881 and Chromodoris inopinata Bergh, 1905, is not supported by internal anatomy. So scientifics consider all to be forms of Goniobranchus tinctorius.
    Usually there is an irregular white region between the yellow border and the red reticulate pattern which covers most of the mantle. In some animals this white region is absent or can occur just around the anterior end.
    In some specimens the white region is a very regular white submarginal band, and in others small rounded patches of the reticulate pattern form red spots in the white region. Sometimes these spots are uniform red, but usually they have a red reticulate pattern.
   Some colour form lacks the orange or yellow marginal band on the mantle.
All the specimens found in Reunion Island have exactly the same coloration pattern, if you find another colour form please Contact us...
    The mantle, which is wider than the foot, is ovate in outline and flattened in profile.
    The eight to ten, small, simple gills are translucent white and they bear thin red (or more rarely white) stripe up the axis.
    The foot is white
    G. tinctorius feeds on siliceous sponges.
    The ova ( 0.1 mm diameter) occur individually within capsules. Extra-capsular yolk is scattered between the capsules throughout the egg string. Larvae hatch as free-swimming veligers.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Chromodoris tinctoria
   Nudipixel Chromodoris tinctoria

Publications :

Johnson R.F. & Gosliner T.M. (2012) Traditional taxonomic groupings mask evolutionary history: A molecular phylogeny and new classification of the chromodorid nudibranchs. PLoS ONE 7(4): e33479
    Rudman, W.B. (1973) Chromodorid opisthobranch Mollusca from the Indo-West Pacific. Zoological Journal of the Linnean Society 52(3) : 175-199.

Other photos of Goniobranchus tinctorius :

Philibert Bidgrain Rhinophore structure : The lamellate rhinophores are dark red, with the lamellae either specked or edged with white. Gills structure : The eight to ten, small, simple gills are translucent white and they bear thin red (or more rarely white) stripe up the axis.

Philibert Bidgrain Reunion, Etang salé , on the rocky coast Evolution of the colouring pattern during growth

Monika Bachel Reunion, Route en corniche, Saint Denis, 3 May 2009, size : 12 mm The base of the rhinophore is translucent.

Sully Bachel Madagascar, Sainte Marie, October 2008 In this specimen the mantle is opaque white with an important open red reticulations on the central area and flanks.

Christophe Mason-Parker Seychelles, Mahé, Baie Ternay,1 m, October 2011 In this specimen the mantle has a narrow, orange marginal band. (a). The mantle is opaque white with open red reticulations on the central area and flanks The eight to ten, small, simple gills are translucent white and they bear thin red (or more rarely white) stripe up the axis

See more about : Goniobranchus tinctorius variability in Southwest Indian ocean

Reunion, juvenile of Goniobranchus tinctorius (2mm), at Etang salé, by Christophe Cadet

Seychelles, Goniobranchus tinctorius, at Mahé, by Christophe Mason-Parker

Mauritius, Goniobranchus tinctorius, at Riviere Noire, by Pierre Périès