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Hesperolemur
''Hesperolemur'' is a genus of Adapiformes, adapiform primate that lived in the middle Eocene (49-37 million years ago) of southern California. It is an immigrant taxa which appears to be most closely related to the earlier European forms of ''Cantius''. It was approximately in weight and was the last surviving notharctine species, probably because of its position in the refugium (population biology), refugia that existed in southern California during the climate deterioration at the end of the middle Eocene. There are no later taxa that appear to have derived from ''Hesperolemur''. The weak but present development of mesostyles and hypocone, pseudohypocone link ''Hesperolemur'' to ''Cantius''. Morphologically, ''Hesperolemur'' is distinct from other notharctine taxa in having a partially fused ectotympanic anulus (anatomy), anulus in the auditory bulla, no stapedial artery, and no lower molar (tooth), molar paraconids. As the specimen used to make these analyses was badly dama ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notharctine
Notharctinae is an extinct subfamily of primates that were common in North America during the early and middle Eocene (55-34 million years ago). The six genera that make up the group (''Cantius'', ''Pelycodus'', ''Copelemur'', ''Hesperolemur'', ''Notharctus'', and ''Smilodectes'') contain species that are among the most primitive of the Adapiformes, adapiform group, which is one of the most primitive groups of primates. The evolutionary history of this subfamily has been comparatively well documented and has been used to argue for evolutionary gradualism. Though it is generally accepted that adapiforms gave rise to modern day lemurs and lorises, it is not currently known which branch of Adapiformes these living species are most closely related to. Notharctines became extinct in the middle Eocene, most likely because of a combination of factors including climatic change and competition with other North American primates. Taxonomic diversity Notharctinae is one of the two subfamili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |