The Subspecific Status of Two Central American Sloths

The paper reclassifies two Central American sloth taxa from full species to subspecific rank based on comparative morphological evidence. For the three-toed form described as ignavus, skull proportions, mandibular extension, palate characters, and pelage coloration are found to overlap with griseus and include morphological intergrades, prompting its designation as Bradypus griseus ignavus. For the two-toed form mexicanus, variation in dorsal color and auditory bulla size, along with intermediate specimens between northern and southern populations, supports recognizing it as Cyclopes tridactylus mexicanus. The study summarizes examined specimens, geographic occurrences, and the anatomical grounds for the revised name combinations.