Description

Meizonyx salvadorensis — A large megalonychid ground sloth, Meizonyx was part of the diverse group of xenarthrans that evolved in South America and later dispersed northward during the Great American Biotic Interchange. It likely weighed between 800–1,200 kg, stood roughly 1.5–2 m tall at the shoulder when on all fours, and could rear up over 3 m in height to reach vegetation. Its thick fur, elongated claws, and robust limbs indicate a mixed feeder—browsing on shrubs and low-hanging leaves in humid montane forests.

Fossil remains are known primarily from Barranca del Sisimico, El Salvador, and Sistema Huautla, Oaxaca, Mexico, including skulls, mandibles, and postcranial elements. Radiocarbon dating places the Mexican specimen at approximately 12,560 years BP, making Meizonyx one of the last surviving ground sloths in Central America.

Anatomically, it was related to Megalonyx jeffersonii and Xibalbaonyx oviceps, showing adaptations for both terrestrial locomotion and limited climbing ability, possibly for sheltering in rocky outcrops or cave mouths. Its disappearance coincided with late Pleistocene climatic shifts and the spread of humans through Mesoamerica.