This species has been observed on Mauritius and Mayotte Islands

Order : Pleurobranchomorpha Superfamily : Pleurobranchoidea Family : Pleurobranchidae Distribution : Indo-West Pacific Maximal size : 500 mm Abundance : Species characteristics : The observed body colors were a very light gray, mottled gray, light tan, dark brown, and black. Many of the individuals had prominent dorsal projecting papillae often with bright pink or yellow rings encircling the base of each tubercule.
	Showing species characteristics...	Photo Yann von Arnim Mauritius, "Mahebourg Marine Farm", 23 m, 5 April 2011, size : 220 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow
    Synonymous : (according Worms)           
               - Pleurobranchus moebii Vayssière, 1896     

Bibliographic data :

  In some specimens, the mantle is covered in groups of tubercles which are pale on a reddish background. The arrangement is encircled by a dark red or purple line followed by a white line. The space left between the tubercle groups is very pale
    The juvenile is paler than the adults, and the central tubercle in each group isn't elongated. The rhinophores are pale for their distal halves in juveniles, otherwise orange
    The central tubercle is very long in adults
    This species was first decribed from Mauritius in 1832 by Quoy & Gaimard
    This pleurobranch is similar in shape and colour to the Mediterranean species P. testudinarius.
    The non-tuberculated specimens looks like some specimen of P. forskalii but P. mamillatus hasn't the serie of narrow, opaque white semicircles that outline clusters of pustules.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Pleurobranchus mamillatus
   Nudipixel Pleurobranchus mamillatus

Publications :

Goodheart J., Camacho-García Y., Padula V., Schrödl M., Cervera J.L., Gosliner T.M. & Valdés Á. (2015). Systematics and biogeography of Pleurobranchus Cuvier, 1804, sea slugs (Heterobranchia: Nudipleura: Pleurobranchidae). Zoological Journal of the Linnean Society. 174: 322-362.,
    Quoy, J.R. & Gaimard, J.P. (1832). Voyages de découvertes de l`Astrolabe pendant les annees 1826-1829 sous le commandement de M.J. Dumont d`Urville. Zoologie, 2 : 1-686.

Other photos of Pleurobranchus mamillatus :

Yann von Arnim Mauritius, "Mahebourg Marine Farm", 23 m, April 2011   Many of the individuals had prominent dorsal projecting papillae often with bright pink (a) or yellow rings encircling the base of each tubercule (b).

Yann von Arnim Mauritius, "Mahebourg Marine Farm", 22m, 9 December 2010

Yann von Arnim Mauritius, "Mahebourg Marine Farm", 23 m, 8 October 2010, size : 200 mm

Yann von Arnim Mauritius, "Mahebourg Marine Farm", 23 m, December 2010   In some specimens, the mantle is covered in groups of tubercles which are pale on a reddish background. The arrangement is encircled by a dark red or purple line followed by a white line. The space left between the tubercle groups is very pale

 More photos from Indian Ocean

 Mauritius, dark form of Pleurobranchus mamillatus, at Mahebourg, by Yann von Arnim