%0 Journal Article %A Pilar Alda %A Manon Lounnas %A Antonio A. Vázquez %A Rolando Ayaqui %A Manuel Calvopiña %A Maritza Celi-Erazo %A Robert T. Dillon, Jr. %A Luisa Carolina González Ramírez %A Eric S. Loker %A Jenny Muzzio-Aroca %A Alberto Orlando Nárvaez %A Oscar Noya %A Andrés Esteban Pereira %A Luiggi Martini Robles %A Richar Rodríguez-Hidalgo %A Nelson Uribe %A Patrice David %A Philippe Jarne %A Jean-Pierre Pointier %A Sylvie Hurtrez-Boussès %T Systematics and geographical distribution of Galba species, a group of cryptic and worldwide freshwater snails %D 2019 %R 10.1101/647867 %J bioRxiv %P 647867 %X Cryptic species are a major problem in systematics and biogeography, especially if they are invasive or transmit parasites or pathogens. Detecting cryptic species requires a pluralistic approach in which molecular markers allow to detect coherent taxonomical units that can then be analyzed using various markers (e.g., internal morphology) and crosses. In asexual or selfing species, the latter criteria is of limited use. We studied a group of cryptic freshwater snail species from the family Lymnaeidae that invade almost all continents, reproduce mainly by selfing and transmit liver flukes to humans and livestock. We aim to clarify the systematics, distribution and phylogenetic relationships of Galba species based on a sound approach that included morphology, molecular markers, wide-scale sampling (the whole America) and data retrieved from GenBank (therefore including Old World samples). We suggest that the genus Galba comprises five species or species complex. Galba cousini is the only species that can be identified using 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 all cryptic and constitute clades with wide variation in their genetic diversity, geographic distribution and invasiveness. Further genetic studies are required to clarify the status of the G. cubensis/viator (a single or two species). We highlight that no Galba species should be identified without molecular markers and that more sampling is required, especially in North America, Eurasia and Africa to clarify their systematics. We also discuss various hypotheses that can explain crypticity in Galba, such as morphological stasis or stabilizing selection. %U https://www.biorxiv.org/content/biorxiv/early/2019/05/24/647867.full.pdf