Islands represent interesting biogeographic features often defined by unique and dynamic geological and biological components. Such systems serve as examples of the basic fundamental units of biogeographical analyses: areas of endemism. The island of Jamaica is recognized as possessing a unique biota with a large number of herpetofauna species persisting only within the island. Further, Jamaica exhibits a dynamic geologic history characterized by an easterly migration and repeated inundation, resulting in a contemporary biota formed through dispersal. Here, we infer areas of endemism across Jamaica based on 57 amphibian and reptile distributions using Parsimony Analysis and Endemism (PAE). We recover 19 areas of endemism concentrated in two regions: The Blue Mountains region diagnosed by 8 taxa and the west/central limestone plateau region including Cockpit Country and the western Dolphin Head region, diagnosed by 9 taxa. Further discussion on the utility of ambiguous syntaxa in diagnosing extinction, dispersal and ecological patterns as they pertain to biogeographic units is provided.