A juvenile Bothrops asper (Terciopelo) collected in Tamaulipas, Mexico, is identified as the westernmost locality for the species range-wide. We review and map the distribution in Tamaulipas and adjacent areas of San Luis Potosí and Veracruz, Mexico, based on museum and literature records. The specimen was dissected and its stomach contained Cryptotis parva, a novel prey item for the species. We review previous literature reports for specific prey items.