nudibranch with large cerata and hood veil and papillae or low conical tubercle

Melibe viridis (Kelaart, 1858)

This species has been observed on Mayotte and Mauritius Islands

Order : Nudibranchia
Suborder : Dexiarchia
Superfamily : Tritonioidea
Family : Tethydidae
Distribution :Indo west Pacific and Mediterranean (where it has migrated through the Suez Canal)
Maximal size : 300 mm
Abundance :

Species characteristics :

It has a tan ground color, with brown blotches present on notum and cerata, along with dispersed patterns of tiny white flecks or glandular dots.
   Rounded tubercles are present on the notum and cerata
    The large oral hood has a circular, entire margin that produces two to five rows of cylindrical papillae. There are scattered papillae or tubercles on the surface of the oral hood.
   The five to nine cerata are somewhat flattened. They are arranged in two rows on either side of the dorsum.
   The well-separated perfoliate rhinophores arise from the surface of the oral hood within cylindrical sheaths bearing low tubercles.

Showing species characteristics...

Emmanuelle Aigle/ Fabrice Schubert
Mayotte, Mliha, 8 m, 14 January 2011, size : 200-300 mm

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow
    Synonymes (d'après worms) :
          - Melibaea viridis Kelaart, 1858                                      - Melibe rangi Bergh, 1875
          - Melibe fimbriata Alder & Hancock, 1854                       - Melibe vexillifera Bergh, 1880
          - Melibe japonica Eliot, 1913                                          - Meliboea veridis Kelaart, 1858
         - Melibe mirifica (Allan,1932)                                            - Propemelibe mirifica Allan,1932

Bibliographic data :

The large oral hood has a circular, entire margin that produces two to five rows of cylindrical papillae, which taper to conical points, with the innermost row being the longest. There are scattered papillae or tubercles on the surface of the oral hood.
    The well-separated perfoliate rhinophores have 5 to 7 lamellae and arise from the surface of the oral hood within cylindrical sheaths bearing low tubercles. A posterior sail is absent from the rhinophore sheath, but a simple papilla is commonly present on the posterior side of the sheath of most of the animals examined.
    The five to nine cerata are somewhat flattened, saccate, oval to cylindrical with tubercular and papillate surfaces whose dark blotches persist in preservation They are arranged in two rows on either side of the dorsum, the anteriormost opposite, with the remainder alternate and increasingly offset toward the posterior.
    The anus is located immediately anterior to the second ceras on the right side of the body.
    The gonopore is on the right side of the body below and slightly anterior to the first ceras. A ring of papillae is associated with the gonopore
    There are a number of benthic species of Melibe in the tropical Indo-West Pacific. Their most unique attribute is their method of feeding.
            - They have lost their radular teeth and have developed the oral veil into a large veil or "fish net" which they use to constantly scan the substrate as they crawl along.
            - When the sensitive papillae on the inner edge of the oral veil touch a small crab or crustacean the edge of the veil is rapidly contracted, trapping the prey, which is then ingested.
            - Some species of Melibe, but not this species, harbour zooxanthellae in their bodies.
    These animals appear to be feeding on crustaceans, which they are able to ingest intact. The stomach of the 13 cm specimen from Mozambique contained the carapace of a crab, 13 mm across, nearly completely intact. The stomach contents of the 11 cm specimen from the Philippines included several intact ostracods, each approximately one mm in length, and a hermit crab in a snail shell two mm in height
    It seems to have a white dextrally spiralling egg ribbon attached on the sandy substrate
    Found on shallow sandy areas in 2-15 m. Active diurnally and nocturnally

References :

Bill Rudman Seaslug site : Sea Slug Forum : Melibe viridis
Nudipixel Melibe viridis

Publications :

Gosliner, T.M. (1987) Review of the nudibranch genus Melibe with description of two new species. The Veliger, 29 : 400-414
Gosliner, T. M. and. Smith, V. G. (2003). Systematic review and phylogenetic analysis of the Nudibranch genus Melibe (Opisthobranchia: Dendronotacea) with descriptions of three new species. Proceedings of the California Academy of Sciences, Vol 54, (18) : 302–355
Kelaart, E.(1858). Descriptions of new and little known species of Ceylon nudibranchiate molluscs and zoophytes. Journal of the Royal Asiatic Society Ceylon Branch, Colombo 3(1) : 84–139.

Other photos of Melibe viridis :

Emmanuelle Aigle/ Fabrice Schubert

Mayotte, Mliha, 8 m, 14 January 2011, size : 200-300 mm

The well-separated perfoliate rhinophores (a) have 5 to 7 lamellae and arise from the surface of the oral hood within cylindrical sheaths bearing low tubercles.

The large oral hood (b) has a circular, entire margin that produces two to five rows of cylindrical papillae.