Dermatobranchus albus ( Eliot, 1904 )

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This species has been observed on Reunion, Mayotte and Madagascar Islands


Order : Nudibranchia
Suborder : Dexiarchia
Superfamily : Arminoidea
Family : Arminidae
Distribution : Indo-West Pacific
Maximal size : 10 mm
Abundance :


Species characteristics :

It is characterised by longitudinal low ridges and grooves, which are not parallel to the median line. The ridges are white and have a yellow crest. The grooves are darker translucent grey or whitish.

The rhinophores stand vertically or point forwards and bear vertical lamellae. The base is white, the main part black, the apex truncated and yellow

The large velum and the mantle are edged with bright yellow

dermatobranchus albus
Showing species characteristics...

Photo Philibert Bidgrain
Mayotte, Mtsanga Tanaraki, less 1 m, 25 July 2010, size : 10 mm

See more about : Sightening and mating periods
   See more about : Dermatobranchus albus variability in Southwest Indian ocean

Remarks :

Identification confirmed by Nathalie Yonow
    Reunion Island specimens presents some differences with the classical coloration pattern (Eliot description) :
                  - They have a very pale coloration on the notum
                  - The rhinophores have only a faint black coloration on the upper part of the rhinophoral club.
    Synonymous : (according Worms)
               - Pleuroleura alba Eliot, 1904

Bibliographic data :

There are about eight longitudinal ridges (vertical lamellae) on the rhinophoral club
    The foot is rounded anteriorly with angled corners
    On the ventral surface, both the mantle and the foot are white
    The smaller animal has a similar pattern to the larger one except that many of the yellow ridges on the mantle are discontinuous
    Between the rhinophores the mantle is continuous with the head, unlike Armina which has a ridge and a groove here
    As usual in this family, there are openings of glands all along the edge of the mantle on the ventral side, but there are no lateral lamellae or gills such as occur in Armina.

References :

Bill Rudman Seaslug site : Sea Slug Forum : Dermatobranchus albus
   Nudipixel Dermatobranchus albus

Publications :

Eliot, C.N.E., (1904). On some Nudibranchs from East Africa and Zanzibar. Part V. Proceedings of the Zoological Society of London, 2(1) : 83-105
    Edmunds, M. & Thompson, T.E., (1972). Opisthobranchiate mollusca from Tanzania IV. Pleurobranchomorpha, Dendronotoidea and Arminoidea. Proceedings of the Malacological Society of London, 40(3) : 219-234, fig. 4
    Gosliner T.M. & Fahey S.J. (2011) Previously undocumented diversity and abundance of cryptic species: a phylogenetic analysis of Indo-Pacific Arminidae Rafinesque, 1814 (Mollusca: Nudibranchia) with descriptions of 20 new species of Dermatobranchus . Zoological Journal of the Linnean Society 161: 245356. page(s): 261

Other photos of Dermatobranchus albus :


Philibert Bidgrain

Mayotte, Mtsanga Tanaraki, less 1 m, 25 July 2010, size : 7 mm

There are about eight longitudinal ridges (a) (vertical lamellae) on the rhinophoral club

The eye (b)

In Dermatobranchus, The anterior edge of the mantle (c), behind the rhinophores, is normally incomplete, fused with the head.

We found about 5-7 specimens, crawling on the sandy substrate, just near the beach...


Philibert Bidgrain

Mayotte, Mtsanga Tanaraki, less 1 m, 25 July 2010, size : 10 mm

As usual in this family, there are openings of glands (a) all along the edge of the mantle on the ventral side, but there are no lateral lamellae or gills such as occur in Armina.


Yann Oulia

Reunion, Etang salé, "Petit tombant", 10-15 m, 7 November 2010, size : 10-13 mm

Reunion Island specimens presents some differences with the classical coloration pattern :
     - They have a very pale coloration on the notum
      - The rhinophores have only a faint black coloration on the upper part of the rhinophoral club.


Alain-Benoît Rassat

Madagascar, ledge, 17m, 10 January 2016, size : 10 mm

 


 More photos from Indian Ocean

See more about : Dermatobranchus albus variability in Southwest Indian ocean

Mayotte, Dermatobranchus albus, by Fabrice Schubert

Reunion, a very pale form of Dermatobranchus albus, at Etang salé, by Sully Bachel