The Neotropical region of the Americas is among the most biodiverse places on Earth, but much of this biodiversity is still poorly described and understudied. Data on the region’s biota is essential to protect ecosystems and human health. Most research in the Neotropics has focused on plants and vertebrate animals. However, most animal species are invertebrates, many of which play critical roles in ecosystems. Scorpions are among the oldest lineages of terrestrial animals, and some produce potent toxins that are potentially valuable for medical uses. The genus Tityus, a group of scorpions that occurs throughout the Neotropics, comprises more than 10% of the world’s scorpion species and includes half the scorpion species responsible for dangerous venomous stings in humans. The distributions of some medically important Tityus species appear to be expanding as a consequence of environmental change. Despite their medical and ecological importance, the classification of Tityus is unresolved, hindering the ability of specialists and nonspecialists, including public health officials, to identify them. This project will use modern genomic and morphological data to reconstruct the evolution of Tityus and revise their classification, providing a framework for their identification and enhancing understanding of how they evolved and diversified. Trainees contributing to the project will gain expertise in data collection and analysis. Public outreach efforts from this project will enhance knowledge of scorpions, their medical importance, and their role in terrestrial ecosystems. The project will sequence ultraconserved elements (UCEs) from all major lineages of Tityus across their range and assemble corresponding morphological datasets to reconstruct a comprehensive, time-calibrated phylogenetic tree for Tityus. The phylogeny and morphological characters will then be used, together with data on geographical distributions, to propose a predictive classification for Tityus, inc