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This species has been observed on Mayotte, Madagascar, Seychelles and Zanzibar

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Doridoidea Family : Chromodorididae Distribution : Indian Ocean Maximal size : 50 mm Abundance : Seldom if ever on the fore reef zone Species characteristics : The mantle has a large brownish orange central patch running from in front of the rhinophores to behind the gills, there are irregular black or deep purple markings, sometimes irregular circles, on the orange patch, which is bordered by a sinuous broad black or deep purple line. The mantle outside the sinuous black line surrounding the orange patch is white with a submarginal band of translucent greyish-purple The rhinophore are the same brownish orange as the central patch The gills are orange and white
	Showing species characteristics...	Photo Florence Trentin Mohéli, Chissioua Magnougni, 18 m, 22 December 2004, size : 50-60 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow
    Synonymous : (according Worms)
          - Doris gleniei, Kelaart, 1858
          - Chromodoris gleniei, (Kelaart, 1858)

Bibliographic data :

The large brownish orange central patch has four waves down each side forming paired identations, three between the gills and rhinophores and one just behind the gills
   Midway between the submarginal greyish band and the sinuous black line is a band of milky yellow which on its inside edge runs parallel to the black line and on its outside parallel to the mantle edge
          - Thus in the four indentations along each side, the yellow bands expands into a large subtriangular patch which sometimes has a blackish purple central patch
          - In other specimen the yellow band was broken between some indentations
   The gills
          - The nine gills are essentially triangular in cross section, the outer side being smooth and the other two lamellate
          - They have a white smooth outer face with the two lamellae sides being a translucent orange.
          - The inner edge of each gill where the two lamellate sides join is a darker orange, and it widens in the basal half so that is consists of a central washy orange line bordered by a deeper orange line
          - The edge where each lamellate side joins the outer smooth side is also a darker orange
   The underside of the mantle is translucent white except for purple pigmentation which covers the entire anterior part of the mantle overlap and forms a purple line along the join of the mantle and the body
   The body and the foot are also translucent white except for a marginal band of opaque white on the foot
   Originally described from Sri Lanka (Ceylon) and subsequently reported from Tanzania, Maldives, Chagos, Seychelles, Mayotte and Madagascar, this species appears to have a wide Indian Ocean
   When disturbed the whole of the mantle edge can be raised simultaneously and held up for some seconds, then waved up and down a few times. But sometimes, the anterior edge is flapped when the animal is just crawling
   Goniobranchus gleniei seems to be restricted to the Indian Ocean. From its colour pattern it seems to be a sibling species of the western Pacific species Goniobranchus coi but :
          - In Goniobranchus glenei, the central part of the mantle is an orange-brown colour with deep purple or black markings
          - In Goniobranchus coi, the central region is a dull brown colour with a darker mottling of the same color.

References :

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

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
   Kelaart (E.F.), 1858. – Description of new and little known species of Ceylon nudibranchiate molluscs and zoophytes. J.Roy. Asiatic Ceylon Branch, Colombo , 3(1): 84-139
   Rudman, W.B. (1987a) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: Chromodoris epicuria, C.aureopurpurea, C. annulata, C. coi and Risbecia tryoni colour groups. Zoological Journal of the Linnean Society 90 : 305-407.
   Yonow, N. (1993) Opisthobranchs from the Maldive Islands, including the descriptions of seven new species (Mollusca: Gastropoda). Revue francaise d'Aquariologie, 20(4) : 97-130.

Other photos of Goniobranchus gleniei :

Zanzibar, Goniobranchus gleniei by Arnaud Douay