Diaphorodoris cf mitsuii     (Baba, 1938)

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This species has been observed on Reunion and Madagascar Islands

Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Onchidoridoidea
Family : Calycidorididae
Distribution : Indo West Pacific
Maximal size : 12 mm
Abundance :

Species characteristics :

Our specimens have :
        -) a tuberculate dorsum
        -) an orange line on the crest at the middle of the foot
        -) an orange submarginal band
        -) the rhinophores have an orange subapical region and an opaque white apex

diaphorodoris cf mitsuii
Showing species characteristics...
Photo Sully Bachel
Reunion, Les Avirons, 14 m, 27 November 2010, size : 5-7 mm

See more about : Sightening and mating periods

Remarks :

Identification proposed by Hsini Lin. These specimens differ from the original description. For some author it better to speak of D. cf mitsuii, other considered that it's just a problem of variability (description from a single specimen... )
    The following original description of the species is from Baba (1938) : Diaphorodoris mitsuii (as Lamellidoris mitsuii) from a single specimen, approximately 5 mm in length, dredged from Susaki, Izu.
             -) Length of animal about 5 mm.
             -) Body elongate-elliptical, bluntly rounded at both ends.
             -) Back covered sparsely with small conical tubercles.
             -) Rhinophore-sheath with smooth margin.
             -) Branchial plumes 6, small, simply pinnate, completely retractile within a cavity with smooth margin.
             -) Foot produced behind in a fairly long tail, the anterior end abruptly rounded.
             -) General body-colour yellow, margin of mantle with orange-yellow line fading out to yellow to the edge.
    Synonymous : (according Worms)
          - Lamellidoris mitsuii Baba, 1938

Bibliographic data :

According to the Sea-Slug Forum (Bill Rudman) it's a very variable species:
             -) there are variants with a yellow body, with yellow rhinophores and gills, and an orange-red submarginal band on the mantle
             -) and variants with a white body, with translucent white rhinophores and gills,
                the white variants can have:
                            -) a complete white colour without any marginal or submarginal band
                            -) a yellow marginal band and an orange-red submarginal band or a red marginal band
                            -) In some specimens are marginal and/or submarginal bands on the foot,
                            -) some specimens have a red line on the crest at the middle of the foot
                            -) in some specimens the gills are red to orange tipped and the rhinophores have a reddish to orange subapical region and an opaque white apex
    Etymology : The specific name chosen by Baba (1938) was for Dr. Mitsui, director of the Mitsui Institute of Marine Biology, near Shimoda, Izu, Japan. The MIMB lab made available facilities and help in specimen collecting during Baba's stay there during July of 1937

References :

Bill Rudman Seaslug site : Sea Slug Forum : Diaphorodoris mitsuii
   Slug site from David Behrens Diaphorodoris cf mitsuii
   Okinawa Seaslug Diaphorodoris mitsuii

Publications :

Baba, K. 1938. Three new nudibranchs from Izu, Middle Japan. Annotationes Zoologicae Japonenses 17(2):130-133.
    Rudman, W.B. & Darvell, B.W. (1990). Opisthobranch molluscs of Hong Kong: part 1. Goniodorididae, Onchidorididae, Triophidae, Gymnodorididae, Chromodorididae (Nudibranchia). Asian Marine Biology, 7 : 31-79

Other photos of Diaphorodoris cf mitsuii :

Alain-Benoît Rassat

Madagascar, Nosy bé, 22 m, size : 12 mm

Sully Bachel

Reunion, Les Avirons, 14 m, 27 November 2010, size : 5-7 mm

(a) an orange line on the crest at the middle of the foot

Christophe Cadet

Reunion, Etang Salé on the rocky coast, less 1 m, 20 December 2010, size : 2-3 mm

(a) an orange line on the crest at the middle of the foot

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