Urumacocnus

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Urumacocnus
Temporal range: Late Miocene (Mayoan-Huayquerian)
~11.6–5.3  Ma
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Pilosa
Family: Megalonychidae
Genus: Urumacocnus
Rincón et al., 2019
Species:
U. urbanii
Binomial name
Urumacocnus urbanii
Rincón et al., 2019

Urumacocnus is an extinct genus of megalonychid sloth that lived during the Miocene in Venezuela. The genus contains one known species, Urumacocnus urbanii. Fossils have been found in the Urumaco Formation of Venezuela. [1]

Contents

Etymology

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]

Description

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]

Taxonomy

 

Hapalops

Megalonychidae

Megalonychotherium

Eucholoeops

Pattersonocnus

Megalonyx

Pliometanastes

Ahytherium

Megistonyx

Pliomorphus

Choloepus

Urumacocnus

Acratocnus

Neocnus

Parocnus

Megalocnus

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References

  1. 1 2 3 Rincón, Ascanio D.; Solórzano, Andrés; McDonald, H. Gregory; Montellano-Ballesteros, Marisol (2019-03-04). "Two new megalonychid sloths (Mammalia: Xenarthra) from the Urumaco Formation (late Miocene), and their phylogenetic affinities". Journal of Systematic Palaeontology. 17 (5): 409–421. Bibcode:2019JSPal..17..409R. doi:10.1080/14772019.2018.1427639. ISSN   1477-2019. S2CID   90207481.