Historical Biogeography of the Leptodactylus fuscus Group (Anura, Leptodactylidae): Identification of Ancestral Areas and Events that Modeled their Distribution

PONSSA, MARÍA LAURA; CAFFARO, MATÍAS; DÍAZ GÓMEZ, JUAN MANUEL; MEDINA, REGINA

ZOOLOGICAL STUDIES

ACAD SINICA INST ZOOLOGY

Lugar: Taiwan; Año: 2021 vol. 61

1021-5506

The objective of the present study was to reconstruct the biogeographic history of the monophyleticgroup Leptodactylus fuscus. We carried out two complementary historical biogeographic approaches:one estimates the ancestral areas with the statistical dispersion and vicariance method (S-DIVA). Theother detects disjoint distributions among sister groups, which provides information about barriers thatseparate populations through a spatial analysis of vicariance (VIP method). For that, we used a databaseof species presence records and a topology of a phylogenetic cladogram, both obtained from updatedpublished data that incorporates the current phylogenetic, taxonomic and distributional arrangementsfor the group. For the analysis of ancestral areas, the following areas of the L. fuscus group distributionwere used: the Carribean, Chacoan, Parana, Amazonian and North American in Pacific subregions.The optimal reconstruction obtained with S-DIVA showed five vicariance events, two extinctions and 50dispersals. The spatial analysis of vicariance revealed 19 disjointed sibling nodes and two distributions onnodes removed in the consensus tree. The results suggest that the ancestor of the Leptodactylus fuscusgroup occupied large areas within the Amazon and Chacoan subregions. Due to several dispersal events,the ancestor distribution range may have expanded to the Caribbean subregion. This expansion couldhave occurred during wetter periods, when forests were more extensive, which would have allowed theinvasion of open habitats within humid forest systems. It is important to note that ecological factors andmarine transgressions that occurred during the Miocene could have had a great influence on the currentdistribution of the group.