Sclerodoris tuberculata    Eliot, 1904

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This species has been observed on Reunion and Mayotte Islands


Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Doridoidea
Family : Discodorididae
Distribution : Indo-West Pacific
Maximal size : 75 mm
Abundance : From time to time on the rocky coast

Species characteristics :

This species has many colour forms bright red, orange, greenish-grey or dull brown. Whitish marks on many specimens look like patches of sand caught in the mucous sheet often exuded by sponges to clean sediment off.

One character linking all the colour forms is the excavation or "pit" in the dorsal midline, which mimics a sponge oscule.

The mantle is thrown into a reticulate pattern of ridges which are raised at their junctions into large hard conical tubercles. There is a wide central hump which is more heavily tuberculated and ridged than the margin.

Sclerodoris tuberculata
Showing species characteristics...
Photo Philibert Bidgrain
Reunion, Etang salé on a rocky coast, less 1 m, 31 January 2007, size : 50 mm

See more about : Sightening and mating periods
   See more about : Sclerodoris tuberculata variability in Southwest Indian ocean

Remarks :

Identification confirmed by Bill Rudman and Nathalie Yonow
    Synonymous : (according Worms)
          - Doris castanea, Kelaart, 1858
          - Sclerodoris rubra, Eliot, 1904

Bibliographic data :

In some specimen, lateral dark pits which mimic sponge oscules are present.
    The entire dorsum is covered with closely spaced sessile caryophyllidia about 50 Ám long ( microscopic observation...) each consisting of a central tubercle surrounded by flattened spicules, usually six in number, arranged in a star-shaped pattern
    The underside of the mantle and die side of the foot, in both specimens, are pale orange with a closely scattered pattern of diffuse purple-brown spots. The sole of the foot in both specimens is a beautiful milky orange
    The rhinophore sheaths are conspicuously raised and are slightly crenulate at the edge. The rhinophore stalk does not extend out very far, the rhinophore club ( 26 lamellae in a 35 mm preserved length ) usually being all that is visible. In the dark greenish grey specimen the basic colour of the rhinophore is dark reddish brown and in light orange-brown specimen it is orange brown. In both specimens there are white edges to the lamellae and a white tip to the club.
    There are eight tripinnate or quadripinnate gills. In both specimens the dorsal or inner side and pinnules are a creamy white and the basal stalk and outer side of the gill axes are similar in colour to the background colour of the mantle. There is also white speckling all over the gills.
      The gill pocket is not conspicuously raised and faces slightly backwards, being situated at the posterior end of the main central raised region of the animal.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Sclerodoris tuberculata
   Nudipixel Sclerodoris tuberculata

Publications :

Rudman, W.B. (1978) The dorid opisthobranch genera Halgerda and Sclerodoris from the Indo-West Pacific. Zoological Journal of the Linnean Society, 62 : 59-88.
    Valdés, A. and Gosliner, T. M. (2001) Systematics and phylogeny of the caryophyllidia-bearing dorids (Mollusca, Nudibranchia), with descriptions of a new genus and four new species from Indo-Pacific deep waters. Zoological Journal of the Linnean Society 133: 103-198.

Other photos of Sclerodoris tuberculata :


 

Matthias Deuss

Mayotte, Ilôt "des aviateurs", 15 November 2011, size : 10-15 mm

 

A strange color form of this species see p195 in NSSI, Nudibranch & Sea Slug Identification, Indo-Pacific, Gosliner, Valdés & Behrens, 2015

 


Philibert Bidgrain      Detail from upper specimen. (Reunion, Etang salé on a rocky coast, less 1 m, 31 January 2007, size : 50 mm )


    

There are eight tripinnate or quadripinnate gills. There is a white speckling all over the gills.

 

The underside of the mantle and die side of the foot, in both specimens, are pale orange with a closely scattered pattern of diffuse purple-brown spots. The sole of the foot in both specimens is a beautiful milky orange


 

Philibert Bidgrain

Reunion, Etang salé on a rocky coast, less 1 m, 31 January 2007, size : 40 and 50 mm

Two color forms closely associated under a rock.

Mating behavior ?

 

 

 

The dorsum has an irregular network of short ridges. In the junctions of two or more ridges, they are raised into a conical tubercle (a) .

 

The rhinophore sheaths are conspicuously raised and are slightly crenulate at the edge (b).
    The rhinophore stalk does not extend out very far, the rhinophore club ( 26 lamellae in a 35 mm preserved length ) usually being all that is visible.
   The basic colour of the rhinophore is dark reddish (c) brown to orange brown. There are white edges to the lamellae and a white tip (c) to the club.

 


 

Hugues Flodrops

Reunion, Etang salé on a rocky coast, 1 m, 25 September 2007, size : 65, 45 and 25 mm.

3 specimens with the same coloration

 

 




Un pattern de coloration brun-rouge

Christophe Cadet

Reunion, Côte rocheuse d' Etang salé, 1 m, 21 décembre 2009, taille : 40 mm.

Quelque soit la coloration de la face dorsale, le dessous du manteau et les côtés du pied sont orange pâle, parsemés de taches pourpre-brunes diffuses. La plante du pied du pied est d'une belle couleur orange laiteuse


Christophe Cadet

Reunion, Etang salé on a rocky coast, 1 m, 17 October 2009, size : 10 mm.

 

A juvenile form of this species...

 


 

Hugues Flodrops

Reunion, Etang salé on a rocky coast, 1 m, 30 April 2007, size : 18 mm.

A juvenile form of this species... with numerous lateral pits around the wide central hump




   More photos from Indian Ocean

See more about : Sclerodoris tuberculata variability in Southwest Indian ocean

Reunion, orange form of Sclerodoris tuberculata, at Etang salé, by Philibert Bidgrain

Reunion, gills détail of two S. tuberculata, at Etang sale, by Hugues Flodrops  

Reunion, young orange form of Sclerodoris tuberculata, at Etang salé, by Christophe Cadet  

Reunion, orange form of Sclerodoris tuberculata, at Etang salé, by Christophe Cadet

Mayotte, orange form of Sclerodoris tuberculata, at Mboueanatsa, by Philibert Bidgrain


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