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

Order : Nudibranchia Suborder : Doridina Family : Chromodorididae Distribution : Tropical Indo-West Pacific. Maximal size : 35 mm Abundance : From time to time on the fore reef zone Species characteristics : The mantle is a translucent white with a broad yellow edged submarginal opaque white band and characteristic opaque white marks in the dorsal midline. The gills and rhinophores are opaque white with lemon yellow tips
	Showing species characteristics...	Photo Guillaume Boeye Reunion, Cap la Houssaye, 12 m, 3 Jully 2007, size : 20 mm

See more about : Sightening and mating periods
   See more about : Glossodoris pallida variability in Southwest Indian ocean

Remarks :

Identification confirmed by Bill Rudman and Hsini Lin

Bibliographic data :

Material examined by Bill Rudman (1990)

St Gilles reef, Réunion Is., Indian Ocean, Photo only, Dr M Jay, August 1973, Paris Museum , Photo 36D. "A photo of this specimen clearly shows yellow gills and rhinophores"

Other external morphology characteristics

Description of the distinctive opaque white marks in the dorsal midline.

Just in front of the rhinophores is a large white spot which has a tapering white line running from it posteriorly between the rhinophores. The second white marks is an ovate ring around the gills. At the anterior edge of the ring a broad band extends forward in the midline to join a large V shaped mark.
In some specimen like the Reunion Island specimens, the second mark is divided in two distinctive marks, a heart-shaped pattern and a ring around the gills

The edge of the mantle is folded into a serie of semi-permanent undulations.
    The coloration of the foot and the foot border matche that of the mantle.
    The lamellate rhinophores are long and slender. The seven or eight, slender, simple gills surround the anus. The inner and the outer face of each gill are smooth and convex while the two side faces are lamellate.
    This Glossodoris can be found as it crawls about during daylight hours beetween 0 to 30 meters of water.
    Most juveniles start off as translucent clear or white and only get their adult coloration as they grow
    It feeds on siliceous sponges. In Guam, the food has been identified as Hyrtios alatum and H. erceta (Rogers & Paul 1991)
    This species has an opaque white marking on the mantle, similar to that found on G.symmetricus.
It differs from G. symmetricus in having a yellow mantle border (orange-red in G. symmetricus), similar colour differences on the rhinophores and gills. The form of the opaque white marking looks like a little man in G.symmetricus and a heart-shape pattern in G.pallida. G . Pallida has a foot border similar to the mantle border, when G symmetricus hasn't any foot border.

References :

Bill Rudman Sea slug site : Sea Slug Forum : Glossodoris pallida
   Nudipixel Glossodoris pallida

Publications :

Ruppel, E & Leuckart, F.S. (1828-1830). Mollusca. In : Atlas zu der Reise im nördlichen Afrika von Eduard Ruppell. Neue wirbellose Thiere des rothen Meers. Francfurt am Main , pp. 15-47, pls 1-12
    Rudman, W.B. (1984) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: a review of the genera. Zoological Journal of the Linnean Society, 81: 115-273.
    Rudman, W.B. (1985) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: Chromodoris aureomarginata, C. verrieri and C. fidelis colour groups. Zoological Journal of the Linnean Society, 83: 241-299.
    Rudman, W.B. (1990b) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: further species of Glossodoris, Thorunna and the Chromodoris aureomarginata colour group. Zoological Journal of the Linnean Society, 100(3): 263-326.
    Rogers, S.D. & Paul, V.J. (1991). Chemical defenses of three Glossodoris nudibranchs and their dietary Hyrtios sponges. Marine Ecology Progress Series 77: 221-232
    Hamatani, I. (1995). Two species of Chromodorididae (Nudibranchia), one newly recorded and one newly established, from Middle Japan. Venus, the Japanese Journal of Malacology, 54(2): 101-107

Other photos of Glossodoris pallida:

Sophie Darnis   Reunion, "Les kiosques "at Saint Leu, 17 June 2006, size 15 mm. A small specimen with a pale yellow coloration.

Sophie Darnis Reunion, "La Barge" at Saint Paul, 25 m, 16 December 2006, size 15-18 mm. The edge of the mantle is folded into a serie of semi-permanent undulations but always with very pale yellow coloration

Philippe Cao Van Reunion, "Grotte à requins" (between Saint Leu and Etang Salé), 25 m, 23 March 2007, size : 20 mm The gills (a) and rhinophores (b) are opaque white with lemon yellow tips

Florence Trentin Reunion, "La pierre au préfet" at Saint Gilles, 20 m, 6 June 2010, size : 2 mm. A juvenil form Just in front of the rhinophores is a first white spot (a) which has a tapering white line running from it posteriorly between the rhinophores. In this small specimen, the second white marks (b) is an ovate ring around the gills. At the anterior edge of the ring a broad band extends forward in the midline to join a large V shaped mark.

Vanessa Bechard Mauritius, Flic en Flac 17 m, 2 September 2012, size : 10 mm   The mantle is a translucent white with a broad yellow edged submarginal opaque white band (a) and characteristic opaque white marks in the dorsal midline.

See more about : Glossodoris pallida variability in Southwest Indian ocean

Reunion, Glossodoris pallida, at Saint paul, by Maurice Jay

Reunion, Glossodoris pallida with a very pale yellow edge, at Saint Gilles, by Philibert Bidgrain  

Reunion, Glossodoris pallida, at Saint Leu, by Florence Trentin 

Reunion, Glossodoris pallida crawling on a sandy substrat, at Sainte Rose, by Nicolas Noël  

Madagascar, Glossodoris pallida, at Nosy Bé, by Alain-Benoît Rassat

Seychelles, Glossodoris pallida, at Mahé, by Christophe Mason-Parker