Urumacocnus is an extinct genus of megalonychid sloth that lived during the Miocene in Venezuela.

[1] The generic name, Urumacocnus, is derived from the Urumaco Formation in which its fossils have been found in, and -ocnus, which means "hesitating" or "lazy", which is commonly used to name extinct sloths.

The specific name honours Franco Urbani, for his important contributions to Venezuelan geology.

[1] Urumacocnus is a relatively small sized megalonychid sloth that shares a combination of diagnostic features such as a round femur shaft, a straight femur shaft, albeit with the medial and lateral sides curved the femur head angle with respect to the femur shaft which is more than 160°, the femur neck being well demarcated, a valley between the femur head and the greater trochanter shallow; the femoral head present and larger than in other members of the family; the proximal end of the femur being broader than the distal end, greater trochanter longer than wide and smaller than the head, and entirely positioned distal to the femur head; and the lesser trochanter well developed, and caudally and medially directed.

[1] Hapalops Megalonychotherium Eucholoeops Pattersonocnus Megalonyx Pliometanastes Ahytherium Megistonyx Pliomorphus Choloepus Urumacocnus Acratocnus Neocnus Parocnus Megalocnus