New species of the ground sloth Parocnus from the late Pleistocene-early Holocene of Hispaniola




paleontology, Dominican Republic, Xenarthra, Pilosa, Megalonychidae, taxonomy, Caribbean


Parocnus dominicanus sp. nov. represents a new species of megalonychid ground sloth from the
Altagracia Province of southeastern Dominican Republic. Specimens of multiple individuals, including one
associated partial skeleton, were recovered from two separate underwater caves in the Parque Nacional del
Este through collaborations with museums and cave divers between 2009–2013. Parocnus dominicanus sp.
nov. is distinguished by its small size compared to that of P. serus, with percent differences in limb element
lengths ranging from 13−24%. Numerous cranial and post-cranial elements also exhibit morphological character
states that are not attributable to size variations. The recovery of multiple individuals within each locality
demonstrates a size dimorphism, possibly sexual, which parallels patterns exhibited by P. serus. The two
species are also geographically distinct, with no examples of co-occurrence at any localities to date. Parocnus
dominicanus sp. nov. and P. serus share character states that are distinct from those of the Cuban species, P.
browni, and which suggest differential usage of the forelimb. The exact age of the specimens described here is
unknown, however, Parocnus has been dated to the Holocene in Haiti.


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How to Cite

McAfee, R., Beery, S., Rimoli, R., Almonte, J., Lehman, P., & Cooke, S. (2021). New species of the ground sloth Parocnus from the late Pleistocene-early Holocene of Hispaniola. Vertebrate Anatomy Morphology Palaeontology, 9(1).