A new species of Tambja (Mollusca, Gastropoda, Nudibranchia) from the Mediterranean Sea: description of the first species of the genus from the Balearic Islands and Malta

8 pages, 4 figures, 1 table

A new species of polycerid nudibranchs of the genus Tambja is described from Mallorca Island (Spain) and Malta. So far, only two species of Tambja had been recorded in the Mediterranean Sea with a distribution limited to southern Spain. With Tambja mediterranea sp. nov., the distribution of the genus in the Mediterranean Sea is extended, and the new species represents the first occurrence of Tambja at the Balearic Islands and Malta. Externally, the new species is mainly characterized by having ground orange-red colour, dorsum covered with rounded whitish tubercles, rhinophores red with whitish tips and three gill branches with orange-reddish rachis and whitish branches. In the present paper, external and internal features of T. mediterranea are described and compared with other species of the genus, especially with its most similar species, T. limaciformis. Additionally, phylogenetic analyses (Bayesian and maximum likelihood) based on mitochondrial sequences (COI) show that T. mediterranea sp. nov. is sister to T. divae and that both species cluster together with T. limaciformis and T. amakusana with the maximum support

The specimens studied in this paper were collected with the help of all the participants in the oceanographic survey DRAGONSAL-0712, especially Carmen Barberá, Marta Díaz-Valdés, Aina de Mesa, Francesc Ordinas, Concepció Rodríguez-Prieto,María Valls and Eva Ma Vidal, who sorted the benthos samples. We are very grateful to Constantine Mifsud for collecting the specimens from Malta. The building of this oceanographic vessel was partly financed by the Programme FEDER, FICTS-2011-03-01. [...] The sequences were obtained thanks to the research grant CGL2010-17187 of the Spanish Ministry of Economy and Competitiveness to Juan Lucas Cervera. [...] The present paper is framed within the project FEP311NBAL00001 ‘‘DRAGONSAL’’, supported by the Conselleria d’Agricultura, Medi Ambient i Territori de les Illes Balears, the Spanish Oceanographic Institute and the European Fisheries Fund (FEP)

Peer Reviewed