Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Phyllidioidea
Family : Phyllidiidae
Distribution : Known from three localities in the Indian Ocean: Réunion and Mauritius Island; southern Thailand; and Java (type locality).
Maximal size : 45 mm
Abundance : Frequently on the fore reef zone

The rhinophores are primarily black but grade to pale pink-grey at their bases.

Characterized by its greyish pink to greyish blue tuberculate dorsum, three tuberculate ridges, four narrow black lines.

The outer most black lines extend to the mantle edge anteriorly and posteriorly.

Remarks :

Identification confirmed by Bill Rudman
    Synonymous : (according Worms)
          - Phyllidia gemmata Pruvot-Fol, 1957

Bibliographic data :

In the different specimens found in Reunion and Mauritius Islands, we can observe in the peripheric notum some little black spots or transversal black rays.

According Bill Rudman : "After receiving the Flodrops' recent messages, and then yours, I thought I had better check up on Pruvot-Fol's original description of P. gemmata and was surprised to find that the specimen she illustrates has the radial, or transverse, lines around the mantle edge as in your specimens. So far from being unusual, it appears your animals are "typical" and the one which Brunckhorst illustrates and describes in his monograph is the unusual one.
Pruvot-Fol does not give any locality data in her description of this species - except for mentioning it was in a vial in the British Museum - but Brunckhorst, who studied the British Museum material, gives Java as the locality of the type material. c does not mention the radial lines either, but they are clearly visible in her photograph, which I have reproduced here."

Material examined by David J.Brunckhorst ( see reference/publications).

40 mm specimen, Reunion Island, 1-20 m depth, 1987, M.Jay
    20 mm specimen, Reunion Island, 5-20 m depth, 1989, M.Jay

Other external morphology characteristics

Live specimens ranged in length from 25-45 mm.
    The rhinophores are primarily black but grade to pale pink-grey at their bases and each rhinophoral clavus possesses 19 to 22 lamellae (specimens greater than 34mm).
    The outer most black lines extend to the mantle edge anteriorly and posteriorly.
    Low, compound, conical tubercles are numerous over the notum but do not occur on the black lines.

Florence Trentin

Mating in Saint Leu reef beetween two small specimens

Reunion, "Eboulis reef" at Saint Leu, 15 m, 26 December 2006, size 15-20 mm

Hugues Flodrops

Reunion, "Kelonia" at Saint Leu, 15 m, 1 December 2006, size 35 mm

Olivier Aubrespin

Reunion, Saint Leu lagoon, 22 January 2005.

This specimen present high compound, conical tubercles over the notum but do not occur on the black lines.

Jean-Marie Gradot

Reunion, Trou d'Eau lagoon, less 1 m, 8 February 2015 size : 50 mm

a strange specimen :

The outer most black lines extend to the mantle edge anteriorly and posteriorly

But the rhinophore are decolorated...