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This species has been observed on Mauritius and Madagascar Islands

Order : Nudibranchia Suborder : Euctenidiacea Superfamily : Polyceroidea Family : Polyceridae Distribution : Madagascar Maximal size : 30 mm Abundance : Species characteristics : The green body surface is wrinkled with several darker stripes on the notum and sometimes both sides of the body Rhinophores have a complex pattern of dark blue/violet, green and whitish coloration. The gill branches are dark blue/violet at the tip and whitish and green at the base There is also a dark blue/violet coloration on the tip of the oral tentacle, the posterior end of the body and sometimes on the posterior foot midway from the gill and the end.
	Showing species characteristics...	Photo Alain-Benoît Rassat Madagascar, Olaf, Nosy bé, 18 m, 15 April 2016, size : 20 mm

See more about : Sightening and mating periods

Remarks :

According Hsini Lin this species looks like Roboastra nikolai by there are some differences :               - R. nikolai has the longitudinal lines with color lighter than the mantle, so lighter green or yellowish. But both animals from Madagascar has the lines darker than the mantle color...               - No white color at the posterior lower third of their rhinophores which is present on all the 4 specimens on the paper Pola & al. 2014 (see photo on the right)               - In R.nikolai, oral tentacles and anterior border of the foot are dark blue/violet. (The animal from Madagascar had violet only on the tips of the oral tentacles.) Polymorphism or different species ??? So, for the moment, its better to call this species Roboastra cf nikolai...     With different spelling : R. nikolae (original spelling), R. nikolai and R. nikolasi...

Bibliographic data :

The oral tentacles are smooth, cylindrical, project in front of the head, very well developed and dorsolaterally grooved. They are found in all members of Roboastra and are probably important in tracking down their prey, perhaps by following its mucus trail.
    The body is elongate and limaciform with a long and pointed posterior end of the foot
    There are five small non-retractile gill branches, all of them about the same size
    The head is rounded with a pair of conical perfoliate rhinophores with about 15 lamellae
    Etymology. This species is dedicated to Nikolas Butvill-Camacho, first son of Yolanda Camacho-Garcia, great friend to all the authors of this paper and who participated in the expedition Santo 2006 to Vanuatu, collecting and photographing this species

References :

Bill Rudman Seaslug site : Sea Slug Forum : Tambja sp6

Publications :

  Pola, M.; Padula, V.; Gosliner, T. M.; Cervera, J. L. (2014). Going further on an intricate and challenging group of nudibranchs: description of five novel species and a more complete molecular phylogeny of the subfamily Nembrothinae (Polyceridae). Cladistics . 1-28.

Other photos of Roboastra cf nikolai :

Alain-Benoît Rassat Madagascar, Olaf, Nosy bé, 18 m, 15 April 2016, size : 20 mm   The oral tentacles are smooth, cylindrical, project in front of the head (a) , very well developed and dorsolaterally grooved. They are found in all members of Roboastra and are probably important in tracking down their prey, perhaps by following its mucus trail.

Yann von-Arnim Mauritius, Mahebourg Aquacole Farm, 20 m, 28 November 2017, size : 25 mm

Alain-Benoît Rassat Madagascar,Secret de la Licorne, 22 m, 16 October 2013, size : 30 mm

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