Genetic evidence of two species in the Biomphalaria havanensis complex (Gastropoda. Planorbidae) from Cuba

In Cuba, several species of freshwater gastropods belonging to the genus Biomphalaria have been described according to morphological characters. However, the taxonomy of this group remains unclear and a number of synonyms are often cited in the literature. This is the case for B. havanensis whose taxonomical status is not well established. Multilocus enzyme electrophoresis at 18 loci was carried out on adult snails of B. havanensis from the type locality in Havana and from several other sites harbouring a morphologically slightly different form, referred to here as Biomphalaria sp. Another local distinct species B. helophila was used as an outgroup. Allelic distribution showed the presence of nine and 12 diagnostic loci between B. havanensis and Biomphalaria sp. and B. helophila, respectively. We detected eight fixed alleles between Biomphalaria sp. and B. helophila. The genetic divergence estimated by absolute genetic distances strongly supports the assumption that Biomphalaria sp. is quite different from the sympatric B. havanensis, morphologically the closest species.