Phylogeny of the Lymnaeidae. The tree was obtained by concatenating the 16 S, ITS-1 and ITS-2 sequences, and includes 50 species and three outgroups. Colored branches represent geographic origin; blue = Australasian; red = Eurasia; brown = Africa and Indic ocean; ochre = North America; green = Central and South America. Species naturally or experimentally serving as intermediate hosts of Fasciola hepatica (H), F. gigantica (G) or refractory to infection (Ø) are shown. (n) is the haploid number of chromosomes. Values on nodes represent bootstrap percentages (BP) and posterior probabilities (PP; given within parentheses). Species sequenced by us are in bold characters.