Anatomy, possible sexual dimorphism, and phylogenetic affinities of a new mylodontine sloth from the late Pleistocene of intertropical Brazil

<i>Glossotherium phoenesis</i> sp. nov. from the late Pleistocene of intertropical Brazil is described and compared with <i>Glossotherium robustum</i> and <i>Glossotherium tropicorum</i>. Compared to these two species, the main differences occur in the shape of the nasal region and pterygoids, proportionate narrowing of the skull, length and arrangement of the tooth rows, degree of projection and form of the mandibular symphysis, height at various points along the dentary, and proportions of the radius, among others described. Clear differences in two well-preserved skulls of the new species are interpreted as representing sexual dimorphism, as occurs in other ground sloths such as <i>Paramylodon</i> and <i>Eremotherium</i>. Other notable features are described for osteoderms and for the ontogenetic developments of the mandible and dentition. The new species <i>G. phoenesis</i> appears to be one of the most derived Mylodontidae, sister taxon of <i>G. tropicorum</i>, and closely related to <i>Pleurolestodon</i>. http://zoobank.org/urn:lsid:zoobank.org:pub:3F1BAFDB-FC4A-442E-ADFD-692EB2DC7655