The collection of reptiles and amphibians is comprised of more than 140,000 specimens.
The collection is extremely rich in snake species, with 359 genera and 954 species represented. The remaining herp groups are represented as follows: lizards (165 genera, 776 species), tuataras (1 genus, 1 species), turtles (54 genera, 104 species), crocodilians (8 genera, 15 species), frogs (143 genera, 682 species), salamanders (38 genera, 151 species), and caecilians (12 genera, 19 species).
The collection contains 52 holotypes (specimens representing species new to science), which is a disproportionately large number for a collection of this size. The herpetology collection is worldwide in scope. The snake skeletal collection is among the largest and most diverse in the world.
The collection of amphibians and reptiles from the Mexican state of San Luis Potosí is the largest in the world, and the collections from Honduras and Peru are among the top five in the world. Approximately 55-60 percent of the currently recognized genera of snakes are represented in the collection.