Reconstruction of past distribution for the Mongolian toad, Strauchbufo raddei (Anura: Bufonidae) using environmental modeling

The use of ecological models enables determining the current distribution of species, but also their past distribution when matching climatic conditions are available. In specific cases, they can also be used to determine the likelihood of fossils to belong to the same species—under the hypothesis that all individuals of a species have the same ecological requirements. Here, using environmental modeling, we reconstructed the distribution of the Mongolian toad, Strauchbufo raddei, since the Last Glacial Maximum and thus covering the time period between the Late Pleistocene and the Holocene. We found the range of the species to have shifted over time, with the LGM population clustered around the current southern range of the species, before expanding east and north during the Pleistocene, and reaching the current range since the mid-Holocene. Finally, we determined that the ecological conditions during the life-time of the mid-Pleistocene fossils attributed to the species in Europe were too different from the one of the extant species or fossils occurring at the same period in Asia to belong to the same species

Pleistocene Faunal Fossils from Bayangol I Site, Bulgan Aimag, Mongolia

During excavation of the Bayan-gol I Palaeolithic site in the Bulgan Aimak, Mongolia, some faunistic remains were recovered attributable to Aves (two species), Anura (two species), and mammals (three species). The fossil remains bear a considerable similarity to the corresponding species of today in Mongolia

Relationship between anuran larvae occurrence and aquatic environment in septentrional east Palearctic landscapes

The presence of amphibian larvae is restricted by both biotic and abiotic variables of the environment. Some of these variables are still undetermined in the septentrional eastern Palearctic where Rana amurensis, Strauchbufo raddei and Dryophytes japonicus are found in large numbers. In this study, we sampled 92 sites across Mongolia, Russia and the Democratic People’s Republic of Korea and measured biotic and abiotic water variables, as well as the height of flooded terrestrial and emergent aquatic vegetation at the breeding site. We determined that the presence of anuran larvae is generally, but not always, linked to pH and temperature. Rana amurensis was not significantly affected by any of the variables measured, while S. raddei was impacted by water conductivity and D. japonicus by pH, temperature and vegetation. Our results highlight a potential risk for these species due to the changes in aquatic variables in response to desertification