Two new species of the genus Aldisa Bergh, 1878 (Gastropoda, Heterobranchia, Nudibranchia) from southern Mozambique

The genus Aldisa Bergh, 1878 is relatively poorly studied. Up to now, no species have been described from the Western Indian Ocean. Two new species of the genus Aldisa are described from Zavora (Mozambique), Aldisa fragaria sp. nov. and Aldisa zavorensis sp. nov. Both species are characterized by having two oval depressions on the dorsum, a red mantle with yellowish-white patches and red rhinophores. Moreover, Aldisa fragaria sp. nov. has large round tubercles on the dorsum tipped in black and a large flattened oral glandular mass, while A. zavorensis sp. nov. has tan gills, rounded red tubercles, branchial and rhinophores sheaths distinctively serrated, and a large oral gland mass with a semi-spherical shape. Partial sequences of mitochondrial (COI and 16S) and nuclear (H3) markers of both species are provided. Both anatomical and molecular data confirm that these species are different from other known species of the genus.