Late Pleistocene carnivoran fossils from Calera cave system, San Luis Potosí, Mexico

The Calera cave system in the Sierra de El Abra, San Luis Potosí, Mexico, preserves an exceptionally diverse Late Pleistocene vertebrate assemblage, including 24 specimens of the order Carnivora. They include Smilodon fatalis, cf. Panthera atrox, cf. Puma concolor, Aenocyon dirus, Canis latrans, Tremarctos floridanus, Nasua, and cf. Procyon. Recovery from this challenging cave requires vertical and underwater caving methods. Fossils were radiocarbon dated using bioapatite, yielding late Rancholabrean ages between ~31,000 and 12,700 cal yr BP. Remarkably preserved cranial and postcranial material permitted detailed taxonomic and ontogenetic analysis, including a growth sequence in S. fatalis from juvenile to senescent individuals. These findings indicate the presence of a diverse predator guild over time and suggest potentially complex trophic interactions within the paleoecosystem, although the taxa may not have been strictly contemporaneous, as the dated specimens span roughly 20,000 years.