Citizen science can improve the knowledge of poorly known herpetofauna in Mongolia

In this study, we initially synthesized iNaturalist records ( n = 909) for herpetofauna of Mongolia. We retrieved iNaturalist records spanning the period from 2008 through 31 August, 2025. Based on our synthesized records, we primarily investigated extensions of species distribution range and Species Distribution Models. Two species were recorded more than 100 times in iNaturalist, including Phrynocephalus versicolor ( n = 355) and Strauchbufo raddei (n = 169). In addition, we initially provided potential distribution ranges for two country new records; including P. kulagini and P. hispidus in Mongolia based on both iNaturalist records and our previous findings. We extended distribution range of seven reptiles based on citizen science records. Among these extensions, P. versicolor’ s distribution range extended remarkably (with additional 143,549 km 2 ) based on non-duplicate out-of-range iNaturalist records ( n = 67) in Mongolia. Finally, we reconstructed SDM maps of P. versicolor and S. raddei using both experts’ and iNaturalist data to compare quality and suitability. Among SDM maps, the integrated data-based (experts’ + iNaturalist) model showed more appropriate climatically suitable habitat for P. versicolor in Mongolia. Therefore, our findings highlight that integrating citizen science data with expert knowledge substantially improves the accuracy and spatial resolution of species distribution assessments.