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

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Polyceroidea Family : Aegiridae Distribution : Indo-West Pacific. Maximal size : 140 mm Abundance : Frequently on the fore reef zone Species characteristics : This nudibranch has a yellow background colour, with a pattern of diagonal and transverse black lines arranged in a network over the entire body. The rhinophores are yellow. The gills are situated midway along the body, partially hidden by three large lobes.
	Showing species characteristics...	Photo Sandrine Flodrops Reunion, "Le canyon" at saint Gilles, 14 m, 26 November 2006, size : 45 mm

See more about : Sightening and mating periods
   See more about : Notodoris minor variability in Southwest Indian ocean

Remarks :

Identification confirmed by Bill Rudman
    Synonymous : (according Worms)
               - Aegires minor (Eliot, 1904)

Bibliographic data :

In juveniles, we can observe black tips to the rhinophores in this species of nudibranch.
    Notodoris minor, is a dorid nudibranch which is very well camouflaged to look like the sponge it feeds on. It feeds on calcareous sponges belonging to the Leucettidae family. On the Great Barrier Reef, it has been found feeding on the calcareous sponge Pericharax heterorhaphis and Gosliner et al. (1996) have recorded it eating Leucetta primigenia elsewhere in the Indo-West Pacific. It is often found on coral substrates, but its distribution is dependent on the presence of its food sponges. It has been found from 3 to 24 m in depth.
    Often they are found with a large pile of cleaned sponge spicules alongside their feeding site. It almost looks as if they are dissolving the sponge tissue away from the spicules before feeding on the resulting soup. If so, this would be an interesting discovery. The alternative is that the spicules are eaten in conjunction with the sponge tissue and then passed out in the faeces, but the way the spicules are usually piled up suggests this is not the case.
    The yellow eggs of this nudibranch are laid near the sponge that the adult feeds on, but this is not to provide food for the young. The hatching young must undergo a larval veliger stage that will see them drifting in the water column at the whim of the ocean currents. The veligers are ready to settle when a combinaison of factors has been met, such as favourable environnemental conditions, maturation time or some other triggerlike food avaibility.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Notodoris minor
   Nudipixel Aegires minor

Publications :

Eliot, C.N.E. (1904). On some nudibranchs from East Africa and Zanzibar. Part V. Proceedings of the Zoological Society of London, 1904(2) : 83-105, Pls. 3-4.
    Fahey S.J. & Gosliner T.M. 2004. A phylogenetic analysis of the Aegiridae Fischer, 1883 (Mollusca, Nudibranchia, Phanerobranchia) with descriptions of eight new species and a reassessment of Phanerobranch relationships. Proceedings of the California Academy of Sciences , (4) 55(34): 613–689
    Gosliner, T.M. Behrens, D.W. & Williams, G.C. (1996). Coral reef animals of the Indo-Pacific . Sea Challengers, Monterey, California. 314 pp.
    Marshall, J.G. & Willan, R.C. (1999). Nudibranchs of Heron Island, Great Barrier Reef. A survey of the Opisthobranchia (Sea Slugs) of Heron and Wistari Reefs . Backhuys Publishers, Leiden, The Netherlands, 257 pp.

Other photos of Notodoris minor :

Photo Christophe Cadet Reunion, Trois bassins, "la souris blanche", 12 m, 21 March 2013, size : 40 mm The yellow eggs of this nudibranch are laid near the sponge that the adult feeds on, but this is not to provide food for the young.

Photo Marina Poddubetskaia "Malen", Pereybère, Mauritius, 18 m, 18 October 2002, size : 30-35 mm In this specimen (usually in juvenile...) , we can observe black tips to the rhinophores. les bouts des rhinophores de ce spécimen sont noirs : c'est un caractère juvénile.

Photo Emmanuel Eby Reunion, Saint Leu, 14 May 2004

Florence Trentin Reunion, Diving site is "Maison verte" at St-Leu, 18 m, size 60 mm, 16 December 2004.

Emmanuel Eby Reunion, Saint Leu, 18 November 2004

Philibert Bidgrain Réunion, Trou d'eau lagoon, less 1 m, 16 November 2010, size : 25-30 mm Black lines sometimes quite irregular in shape

Sophie Darnis "Sea Fan Valley", Poste de Flacq, Mauritius, 15-20 m, 8 May 2009, size : 12-15 mm The rhinophores are yellow without black tip....

Alain Barrère Madagascar, Andavadoaka, November 2005, size : 15-17 mm In this small specimen ( juvenile form...) , we can observed black tips to the rhinophores (a) .

See more about : Notodoris minor variability in Southwest Indian ocean

Mauritius Island, Notodoris minor, at Recif Water Lily, by Mathieu bayon

Reunion, Notodoris minor, by Maurice Jay

Rodrigues, Notodoris minor, at Grand baie, by David Caron

Reunion, Notodoris minor, at Saint Leu, by Florence Trentin 

Reunion, gills details of Notodoris minor, at Etang salé lagoon, by Christophe Cadet 

Reunion, Notodoris minor mating, at Saint Gilles, by Christophe Cadet