Mexichromis lemniscata (Quoy & Gaimard, 1832)

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This species has been observed on Reunion and Mauritius Islands


Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Doridoidea
Family : Chromodorididae
Distribution : Tropical Indo-West Pacific.
Maximal size : 30 mm usually less than 15 mm
Abundance : From time to time on the rocky coast


Species characteristics :

The mantle is purple with a broad creamy yellow border and three white/yellow bands running from the rhinophores to the gills.

The rhinophore stalk is transparent colourless, the basal half of the rhinophore club is red or orange and the upper half shades of purple.
   It's the same pattern for the gills

The foot colour is uniform bluish-purple .

Durvilledoris lemniscata
Showing species characteristics...

Photo Philibert Bidgrain
Reunion, Etang salé, on a rocky coast, 9 October 2005, size 30 mm

See more about : Sightening and mating periods
   See more about : Mexichromis lemniscata variability in Southwest Indian ocean

Remarks :

Identification confirmed by Bill Rudman and Nathalie Yonow
    Synonymes (d'après worms) :
          - Chromodoris clitonota, Bergh, 1905                 - Durvilledoris lemniscata, (Quoy & gaimard, 1832)
          - Chromodoris luxuriosa, Bergh, 1875                - Glossodoris clitonota, (Bergh, 1905)
          - Chromodoris scurra, Bergh, 1874                    - Glossodoris lemniscata, (Quoy & gaimard, 1832)
          - Chromodoris variegata, Pease, 1871
          - Doris lemniscata, Quoy & gaimard, 1832

Bibliographic data :

More exactly the mantle is a bright bluish-purple with a broad creamy-white band at the mantle edge. There is also a median broad creamy-white band running down the midline from just in front of the rhinophores back to the gill pocket. Flanking the median creamy-white band are a pair of milky-yellow bands, one on each side starting a little behind the rhinophores and running back to finish one on either side of the gills. Separating the flanking yellow bands from the median cream band is a thin reddish-purple line which runs back on to the gill pocket. On the outer edge of each yellow band is a faint trace of a second reddish-purple line.
    In some specimens,the outer edge of the flanking milky-yellow bands has a distinct reddish-purple line so that the mantle has a pair of reddish-purple lines on each side of the broad median creamy-white band. (The two forms exist in Réunion Island, see below)
    More exactly the lamellate rhinophores have a translucent purplish stalk. The bottom third of the rhinophore club is also translucent purplish, the middle third is orange and the upper third purple. At the junction of the orange and purple bands is a line of dark reddish-purple suggesting an overlap of the orange and purple pigmentation
    The gills (10 to 12) are simple and arranged in a circle around the anus
    According Johnson and Boucher (1983) this species lays a white spawn mass. The ova (86 µm of diameter) occur individually within capsules (100-115 µm) and extra capsular yolk bodies are scattered between the capsules throughout the egg string.
    These animals are specialized sponge feeders.
    The name of this genus came from Dumont d'Urville who was in command of the French research vessel the Astrolabe during its great voyage of scientific discovery in the early years of the 19th century. Quoy & Gaimard, the naturalists on board, discovered this beautiful species during the voyage

Material examined by Nathalie Yonow ( see reference/publications).

One specimen collected from Pereybere (Mauritius), 31 October 1985, size : 14 mm.

References :

Bill Rudman Sea slug site : Sea Slug Forum : Durvilledoris lemniscata

Publications :

Boucher, L.M. (1983). Extra-capsular yolk bodies in the egg masses of some tropical Opistobranchia. Journal of Molluscan Studies 49: 232-241
    Johnson R.F. & Gosliner T.M. (2012) Traditional taxonomic groupings mask evolutionary history: A molecular phylogeny and new classification of the chromodorid nudibranchs. PLoS ONE 7(4): e33479
    Quoy, J.R. & Gaimard, J.P. (1832). Voyage de découvertes de L'Astrolabe pendant les années 1826-1827-1828-1829, sous le commandement de M.J. Dumont D'Urville, Zoologie, 2 : 1-686.
    Rudman, W.B. (1984) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: a review of the genera. Zoological Journal of the Linnean Society 81 : 115-273.
    Yonow, N. and Hayward , P. J. (1991). Opistobranches de l'île Maurice, avec la description de deux espèces nouvelles (Mollusca : Opistobranchia) Revue française d'aquariologie herpétologie, 18 (1), 1-30

Other photos of Mexichromis lemniscata :


Philibert Bidgrain. These two specimens was observed in a rocky coast at Etang salé. Reunion,

The left one : size 25 mm, 07 December 2005. The right one : 20 mm, 29 November 2005

Specimen with a pair of reddish-purple lines on each side of the broad median creamy-white band.

Specimen with inner reddish-purple line and outer faint trace of a second reddish-purple line.

Durvilledoris lemniscata
Durvilledoris lemniscata


Philibert Bidgrain

Reunion, Etang salé, size : 30 mm, 11 April 2006

More exactly the lamellate rhinophores have a translucent purplish stalk (a). The bottom third (b) of the rhinophore club is also translucent purplish, the middle third (c) is orange and the upper third purple (d1 and d2). At the junction of the orange and purple bands is a line of dark reddish-purple (e) suggesting an overlap of the orange and purple pigmentation

Sur la grande majorité des spécimens observés le tiers supérieur est en fait formé d'une bande indigo clair (d1) et d'une pointe indigo plus foncé (d2) ...


Philibert Bidgrain Reunion, Etang salé, size 25 mm, 07 December 2005.

18h25 : Sleeping in a crevice, gills retracted...

18h41: Crawling on the substrate, gills extended


Three color variants for the gills

 

Philibert Bidgrain

These three specimens was observed in a rocky coast at Etang salé. Reunion,


Hugues Flodrops

Reunion, Etang salé on a rocky coast, less 1 m, 23 April 2007

A spawning event observed just before the sunshine... With the company of an hermit crab...


Philibert Bidgrain

Reunion, Etang salé, on the rocky coast, less 1 m, 22 December 2009, size :15-18 mm

 

Sur ce spécimen le tiers supérieur est en fait formé d'une bande quasiment blanche (d1) et d'une pointe indigo plus foncé (d2) ...


More photos from Indian Ocean

See more about : Mexichromis lemniscata variability in Southwest Indian ocean

Reunion, Mexichromis lemniscata, at Saint Gilles, by Maurice Jay

Mauritius, Mexichromis lemniscata, at Pereybere, by Nathalie Yonow