Genetic diversity of the freshwater snail Biomphalaria tenagophila (d’Orbigny, 1835) (Gastropoda: Hygrophila: Planorbidae) across two coastal areas of southeast Brazil

Abstract

This study uses two mitochondrial (COI, 16SrRNA) and one nuclear marker (ITS2) to explore genetic diversity between populations of B. tenagophila (d’Orbigny), the most common intermediate host for Schistosoma mansoni in southeast Brazil. The snails were collected in freshwater bodies along the southern coastal region of Ribeira do Iguape river basin and along the northern coastal region of the state of São Paulo, Brazil. The estimates of genetic differentiation between the populations (Φ) indicate that there is no genetic isolation between northern and southern populations. The haplotype diversity observed in B. tenagophila shows a complex pattern of distribution: in the southern region, the genetic variation in B. tenagophila is partitioned into small and more heterogeneous mitochondrial haplotypes, whereas in the northern region there were one to three homogeneous haplotypes. The results may suggest a different colonisation history across the study area.