Systematics and geographic distribution of Galba, a group of cryptic and worldwide species of freshwater snails

ALDA P.

Virtual Meeting

Simposio; American Malacological Society Virtual Meeting; 2020

The American Malacological Society

Cryptic species are a problem in systematics and biogeography, especially if they are invasive or transmit parasites or pathogens. In this work we study a group of cryptic species of freshwater snails of the family Lymnaeidae that inhabit almost all continents and transmit Fasciola to humans and livestock. Our goal is to elucidate the systematics, distribution, and phylogenetic relationships of Galba group species based on a robust and integrative approach that includes GenBank morphology, molecular markers, large-scale sampling (all from America), and DNA sequences (including samples from America and the rest of the world). We conclude that the genus Galba comprises five species or complexes of species. Galba cousini is the only species that can be identified using the shell morphology and internal anatomy (a derived trait) and has the most restricted distribution within the group. The other four species ? G. truncatula, G. cubensis / viator, G. humilis, and G. schirazensis ? are cryptic and constitute clades that vary in their genetic diversity, geographic distribution, and invasive potential. We conclude and emphasize that no Galba species should be identified without molecular markers. We also discussed how morphological stasis could explain crypticity in Galba.