This species has been observed on Reunion, Mayotte, Mauritius and Madagascar Islands
Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Doridoidea
Family : Discodorididae
Distribution :
Tropical Indo-West Pacific
Maximal size : 100
mm
Abundance : Seldom on the reef flat zone
Species characteristics :
The
background colour of the living animals is white or pale cream.There
are dark, large, irregular markings of brown, purple, or grey on the
dorsum. These markings vary in distribution, often covering most of the
dorsum. They are composed of a number of small dark spots, which are
more densely arranged in several areas.
The mantle margin, the foot and the rhinophoral and branchial sheaths are edged by a thin orange or yellow line.
The rhinophores are yellowish, often with darker orange tips.
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Showing species characteristics... |
Photo Philibert Bidgrain
Mayotte, Mtsanga Guini, less 1 m, 3 August 2010, size : 50 mm |
See more about : Sightening and mating periods
Remarks :
Identification confirmed by Angel Valdès
In some specimens from our area, the edge of the mantle, foot,
rhinophore pockets and gill pockets are orange or yellow, but in many
specimens they are not
Synonymous : (according Worms)
- Platydoris eurychlamys, Bergh, 1877
- Platydoris noumeae, Risbec, 1928
Bibliographic data :
This species, with P. formosa, P. striata, P. cruenta and P. cinerobranchia form a group of very similar species.
Remark : Dorgan, K.M., A. Valdés & T.M. Gosliner. 2002 consider that P. cruenta (
Quoy & Gaimard, 1832 ) and P. striata (Kelaart, 1858) are regarded as synonyms.
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P. formosa |
P. scabra |
P.cruenta |
P. striata |
P.cinerobranchiata |
Localisation |
Tropical Indo-West Pacific |
Tropical Indo-West Pacific |
Tropical West Pacific |
Tropical Indo-West Pacific |
Solomon Islands |
Mantle coloration |
Brown spotted
with red patches |
Brown spotted
without red patches |
Brown
lined
with red patches
|
Brown lined
without red patches |
Reddish, or orange patches and no brown specks or lines. |
Rhinophore coloration |
They are uniformly red, with the tips somewhat lighter |
They are
yellowish, often with darker orange tips. |
They have a dark brown clavus with white flecks on the lamellae |
They are dark red or brown |
They are dark red or brown |
Underside of the mantle and foot |
The
underside is white and has many large, bright orange red spots (not
always easily visible). These spots are larger and densely concentrated
near the foot, where some of them can be fused together |
The underside of the mantle is dirty white and there are some brown speckles on the side of the foot. |
The
underside of the mantle is white with brown lines near the foot, and
scattered red patches. The sole of the foot can also have brown lines |
The underside of the mantle is white without red patches |
The underside of the mantle is white with red patches |
The brown patches on the mantle are arranged more or less symmetrically either side of the midline.
The gill is composed of five to six tripinnate branchial leaves. The
branchial leaves are white with irregular dark lines on the rachis of
the lamellae.
The opening of the branchial sheath has five to six lobes, with the anterior and posterior ones being larger than the others.
The perfoliate rhinophores have 37 lamellae in one specimen examined. They are yellowish, often with darker orange tips.
The underside of the mantle is dirty white and there are some brown speckles on the side of the foot.
Species of Platydoris
are easily recognized by their flattened, normally rigid (or
coriaceous) body. This genus is also characterized by the dorsum
covered with very small caryophyllidia and generally a lobate branchial
sheath
It probably feeds on siliceous sponges
Found on shallow water under coral heads. Often crawling in the open during the night
Breeds from May to september in Red Sea, laying an orange yellow ribbon
in a spiral approximatively 100 mm across (Soliman, 1978)
References :
Bill Rudman Seaslug site : Sea Slug Forum : Platydoris scabra
Nudipixel Platydoris scabra
Publications :
Dorgan, K.M., A. Valdés & T.M. Gosliner. 2002. Phylogenetic systematics of the genus Platydoris (Mollusca, Nudibranchia, Doridoidea) with descriptions of six new species. Zoologica Scripta. 31(3): 271-319.
Soliman, G. N. 1978 The redescription, reproductive and development of
the Dorid Nudibranch Platydoris csabra (Cuvier) from the northwestern
Red Sea. Journal of Molluscan Studies 44 (2): 151-165.
Other photos of Platydoris scabra :
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Philibert Bidgrain
Mayotte, Mtsanga Guini, less 1 m, 3 August 2010, size : 50 mm
The mantle margin, the foot (a) and the rhinophoral (b) and branchial (d) sheaths are edged by a thin orange or yellow line.
The rhinophores are yellowish, often with darker orange tips (c). |
The gill is composed of five to six tripinnate branchial leaves. The branchial leaves are white with irregular dark lines (e) on the rachis of the lamellae.
The opening of the branchial sheath has five to six lobes, with the anterior and posterior ones being larger than the others.
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Olivier Police Mayotte, Petite-Terre, less 1 m, 25 December 2010, size : 100 mm |
A specimen without orange margin ion the mantle, the foot and the rhinophoral and branchial sheaths
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Olivier Police
Mayotte, Petite-Terre, less 1 m, 25 December 2010, size : 100 mm
A second specimen without orange margin ion the mantle, the foot and the rhinophoral and branchial sheaths
The brown patches on the mantle are arranged more or less symmetrically either side of the midline. |
Christophe Cadet
Reunion, Etang salé, less 1 m, 9 January, size : 35-40 mm
A dead specimen... With the characteristic orange border on the rhinophores, gills and foot...

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More photos from Indian Ocean
Madagascar, Platydoris scabra with pale orange margin, at Andavadoaka, by Alain Barrère
Mayotte, Platydoris scabra with orange margin, at Tanaraki, by Fabrice Schubert
Mauritius, Platydoris scabra, at Pointe d'Esny, by Geoffrey Summers
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