Thecacera pacifica     (Bergh, 1884)

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This species has been observed on Reunion and Mayotte Islands


Order : Nudibranchia
Suborder : Euctenidiacea
Superfamily : Polyceroidea
Family : Polyceridae
Distribution : Indian Ocean and Western Pacific
Maximal size : 25 mm
Abundance :

Species characteristics :

This species is unmistakeable, bright orange to yellow in colour with blue tips to the partial rhinophore sheaths, gills processes and tail.

There is a black band betweeen the blue and orange pigmentation

The bipinnate gills are orange with black markings on the rachis.

The orange rhinophores are tipped with black

thecacera pacifica
Showing species characteristics...

Photo Emmanuel Eby
Mayotte, Longoni harbourg, 13 Jully 2007

See more about : Sightening and mating periods

Remarks :

Identification confirmed by Nathalie Yonow and Bill Rudman
    All specimens found on books and internet apparently had the "normal unstriped colour pattern", corresponded to Berg description... Ours specimens from Mayotte had extra black & white stripes on the body. This is almost certainly just a colour variant of T. pacifica
    Synonymous : (according Worms)
               - Ohola pacifica Bergh, 1884
               - Thecacera inhacae MacNae, 1958

Bibliographic data :

The blue colour of the tips to the partial rhinophore sheaths, gills processes and tail can varie from light blue to turquoise
    Sometimes there are blue markings on the gills.
    They laying an yellow/orange egg ribbon
    This beautiful species has two elongate extrabranchial appendages

References :

Bill Rudman Seaslug site : Sea Slug Forum : Thecacera pacifica
    Nudipixel Thecacera pacifica

Publications :

Bergh, R. (1883). Beiträge zu einer Monographie der Polyceraden. Verhandlungen der Koniglich-kaiserlich Zoologische-botanischen Gesellschaft in Wein (Abhundlungen), 33 : 135-180, pls 6-10
    Macnae,W. (1958) The families Polyceridae and Goniodorididae (Mollusca, Nudibranchiata) in southern Africa. Transactions of the Royal Society, South Africa, 35(4): 341-372. (Pls.17-18)

Other photos of Thecacera pacifica :


 

 

Karine Bagneres

Reunion 15cm, October 2018

Ours specimens from Reunion had extra black & white stripes on the body 


 

 

Emmanuel Eby

Mayotte, Longoni harbourg, 4 January 2008

They laying an yellow/orange egg ribbon

Ours specimens from Mayotte had extra black & white stripes on the body (a)


 More photos from Indian Ocean

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