Aldisa cf. albatrossae  Elwood, Valdès, & Gosliner, 2000

Version française...

This species has been observed on Madagascar Island

Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Doridoidea
Family : Cadlinidae
Distribution : Madagascar
Maximal size : 20 mm
Abundance :

Species characteristics :

The dorsum is bluish to grey, darker at the edges with numerous whitish tubercles

Black marks between the rhinophores and before the gills

Yellow-orange marks are present at the level of the rhinophores and the gills

Rhinophores and gills whitish to grey

Aldisa albatrossae
Showing species characteristics...

Photo Alain-Benoît Rassat
Madagascar, Pterois, Nosy bé, 12 m, 1 October 2013, size : 20 mm

Remarks :

This species looks like Aldisa albatrossae but there is one difference :
                 - In ours specimens we don't observed the classical pattern on the black markings on the notum. In Aldisa albatrossae description : " The black pattern begins as a T-shape crossing in front of and between the rhinophores. Behind the rhinophores, the T-shape connects with a black rectangular mark that spans the dorsum to the branchial pocket. Two black lines extend from the rectangular mark around the sides of the branchial pocket." ( partially observed in ours specimens... so Aldisa cf. albatrossae...)
    For some specialists it could be A. andersoni for other A. albatrossae, so for the moment it's better to called this species Aldisa cf. albatrossae

Bibliographic data :

Yellow-orange splotches are present on the dorsum of the living animal. These marks of yellow-orange lie at the front edges of the T of the black mark and along the anterior edge of the rectangular portion of the black mark. Yellow-orange lines also extend from the sides of the branchial pocket to the posterior edges of the dorsum.
    It is similar in coloration to Aldisa andersoni, A albatrossae, A. williamsi and A. erwinkoehleri, but differs in a number of characteristics :


A. andersoni

A. albatrossae

A. erwinkoehleri

A. williamsi


Clearly arranged in rows or ridges.

Randomly distributed.

Black coloration

Found uniformly over the mantle separating the rows of tubercles

Forms a rectangle on the dorsum with a T-shape mark anterior to the rhinophores

Forms concentric rings

Yellow pigmentation

Yellow color markings are more extensive with a yellow saddle behing the rhinophores extending to the edge of the mantle

The yellow color markings are less extensive

No yellow pigmentation.

Arrangement of tubercles around the rhinophoral pockets

Two equally sized tubercles

Four similarly sized equally separated tubercles

Two equally sized tubercles

Two large and two small tubercles


Sri Lanka

Japan, Indonesia

Thailand, Andaman sea.

Papua New Guinea, Sulawesi, Indonesia.

References :

Okinawa Seaslug : Aldisa albatrossae
   Medslug Aldisa albatrossae

Publications :

Elwood, H.R., Valdés, Á., & Gosliner, T.M. 2000. Two new species of Aldisa Bergh, 1878 (Mollusca, Nudibranchia) from the Tropical Indo-Pacific. Proceedings of the California Academy of Sciences 52(14): 171-181, 5 figs.

Other photos of Aldisa cf. albatrossae :

Alain-Benoît Rassat

Madagascar, Nosy bé, 12 m, size : 10 mm

 More photos from Indian Ocean

If you have taken a photo of this species in South West Indian Ocean, please Contact us...