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This species has been observed on Reunion Island

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Doridoidea Family : Chromodorididae Distribution : Tropical and subtropical Indo-West Pacific. Maximal size : 60 mm Abundance : Seldom : on the fore reef zone Species characteristics : The dorsum, sides of the body and posterior end of the foot are green, grey or red, with a number of pale yellowish to orange rounded spots and some blue spots or reticulations.    There are four lateral lobes on each side of the body bearing a number of small tubercles that are clustered together.    Along the medial line of the dorsum there is a single ridge, which extends from the head to a large dorsal wart placed just behind the gill.
	Showing species characteristics...	Photo Emmanuel Eby Reunion, Saint Leu, 3 November 2005, size : 20-22 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Bill Rudman
    In South West Indian Ocean we observed tree color form for this species :
               - "Small yellow dots form" The dorsum is covered with numerous tiny yellow dots. Rhinophores and gills are also covered with tiny whitish dots
               - "Large yellow dots form" The dorsum is covered with large yellow dots. Rhinophores and gills aren't covered with tiny whitish dots, but there is a yellow-green vertical line on the anterior side of the rhinophore
               - "Purple reticulate form " The body is covered with a purple reticule. The rhinophores and gills are dotted with small whitish spots
    Synonymous (according worms) :
          - Ceratosoma sinuatum, (van Hasselt, 1824)
          - Doris sinuata, van Hasselt, 1824
          - Miamira nobilis, Bergh, 1874

Bibliographic data :

Formerly placed in the genus Miamira , Valdes & Gosliner (1999) have recently proposed that these animals are members of the chromodorid genus Ceratosoma.
   Some authors, consider there is a single species which ranges from the green "sinuata" form to the purplish "flavicostata" form. Others consider there are sufficient distinctions in external shape and colour, and radular morphology, to distinguish two or three species. This specimen corresponded to a typical "sinuata" colour form.
    From the medial ridge emerge several lateral ridges that meet the four lateral lobes.
    Extending over the head there is a small lobe with some tubercles, but it does not appear to contain defensive glands. Another similar lobe, but much larger in size and containing defensive glands, extends over the posterior end of the foot. This appears to be homologous to the posterior glandular protuberance of other species of Ceratosoma.
    The lower areas between the lateral lobes are paler, being cream in their inner region. These areas are separated from the centre of the dorsum by a sky blue branched line or spots.
    The perfoliate rhinophores consist of 31 lamellae are pale brownish (greenish to whitish in our specimens) with a number of yellow dots over the lamellar area. The gills, composed of 4-7 tripinnate branches, are pale brownish with a number of red and yellow dots.
    Found on shallow reef 5- 30 m in association with sponges of the genus Dysidea, sometimes together with the opisthobranch Sagaminopteron

References :

Bill Rudman Seaslug site : Sea Slug Forum : Ceratosoma sinuatum

Publications :

Valdes, A. & Gosliner, T. (1999) Reassessment of the systematic status of Miamira Bergh, 1875 and Orodoris Bergh, 1875 (Nudibranchia; Chromodorididae) in light of phylogenetic analysis. Journal of Molluscan Studies, 65 : 33-45.

Other photos of Miamira sinuata :

Barbara Bini Madagascar, Nosy bé, 16 m, size : 30 mm   - "Purple reticulate form " The body is covered with a purple reticule. The rhinophores and gills are dotted with small whitish spots

Emmanuel Eby Reunion, Saint Leu, 3 November 2005, size : 20-22 mm   There are four lateral lobes (yellow arrow) on each side of the body bearing a number of small tubercles that are clustered together. Extending over the head (red arrow) there is a small lobe with some tubercles, but it does not appear to contain defensive glands. "Small yellow dots form" The dorsum is covered with numerous tiny yellow dots. Rhinophores and gills are also covered with tiny whitish dots

Sully Bachel Reunion, Cap la houssaye at Saint Paul, 8m, 30 August 2008, size : 30 mm "Large yellow dots form" The dorsum is covered with large yellow dots. Rhinophores and gills aren't covered with tiny whitish dots, but there is a yellow-green vertical line on the anterior side of the rhinophore

Monika Bachel Reunion, La Possession, 5m, 3 January 2009, size : 8 mm "Large yellow dots form" Presence of a large yellowish marginal band.

Sully Bachel Reunion, La Possession, 6m, 28 December 2008, size : 45 mm Presence of a yellow-green vertical line on the anterior side of the rhinophore "Large yellow dots form"

Sophie Darnis Reunion, Saint Paul, Cap La Houssaye, 7-8 m, 10 October 2010, size : 10-12 mm A small specimen... "Large yellow dots form"

Sully Bachel Réunion, La Possession, 6m, 30 November 2014   Head detail...

Gaétan Hoareau Reunion, Etang Salé, on the rocky coast, less 1 m, 5 February 2016, size : 12 mm A small specimen...

 More photos from Indian Ocean

Reunion, Miamira sinuata with large yellow spot, at Saint Leu, by Raphaël Roland Gosselin

Reunion, Miamira sinuata with tiny yellow dots, at Saint Philippe, by Alain Barrère