''Loxolophus'' is a genus of large arctocyonid from the early Palaeocene of North America. Two species are currently recognised: the type species, ''Loxolophus hyattianus'', and ''L. priscus''.

Taxonomy

Early history

The holotype of ''Loxolophus'' (AMNH 3121), a fragment of the left

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

, was formally described by

Edward Drinker Cope Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American zoologist, paleontology, paleontologist, comparative anatomy, comparative anatomist, herpetology, herpetologist, and ichthyology, ichthyologist. Born to a wealthy Quaker fam ...

in 1885. Cope initially assigned it to '' Chriacus'', and gave it the binomial name ''C. hyattianus''. In the same paper, a single page later, he described ''Loxolophus adapinus.'' Subsequently, they turned out to represent the same taxon, which at some point thereafter was recombined as ''Loxolophus hyattianus''. A second species, ''L. priscus'', was named three years after the initial paper, also by Cope, who similarly assigned it to ''Chriacus''. Subsequently, it was reassigned to ''Protochriacus'' by

William Berryman Scott William Berryman Scott (February 12, 1858 – March 29, 1947) was an American vertebrate paleontologist, authority on mammals, and principal author of the White River Oligocene monographs. He was a professor of geology and paleontology at Pr ...

in 1892, then synonymised with ''Chriacus pugnax'' by

George Gaylord Simpson George Gaylord Simpson (June 16, 1902 – October 6, 1984) was an American paleontologist. Simpson was perhaps the most influential paleontologist of the twentieth century, and a major participant in the modern synthesis, contributing '' Tempo ...

in 1935, and finally was assigned to ''Loxolophus'' by

William Diller Matthew William Diller Matthew FRS (February 19, 1871 – September 24, 1930) was a vertebrate paleontologist who worked primarily on mammal fossils, although he also published a few early papers on mineralogy, petrological geology, one on botany, one on ...

in 1937.

Classification

A phylogenetic analysis by Peter E. Kondrashov and Spencer G. Lucas in 2015 recovered Arctocyonidae as a paraphyletic lineage of archaic ungulates, wherein ''Loxolophus'' forms a sister taxon to a clade consisting of ''

Arctocyon ''Arctocyon'' (from Greek ''arktos'' and ''kyôn'', "bear/dog-like") is an extinct genus of large placental mammals, part of the possibly polyphyletic family Arctocyonidae. The type species is ''A. primaevus'', though up to five other species may ...

'', '' Desmatoclaenus'', '' Protogonodon'', '' Deuterogonodon'' and '' Tricentes''. Another analysis published that year, published by Thomas J. D. Halliday, Paul Upchurch and Anjali Goswami, recovered ''Loxolophus'' as part of a clade also including '' Anacodon,'' '' Oxyclaenus'', and several other traditional arctocyonid genera, distantly related to

pangolins Pangolins, sometimes known as scaly anteaters, are mammals of the order Pholidota (). The one extant family, the Manidae, has three genera: ''Manis'', '' Phataginus'', and '' Smutsia''. ''Manis'' comprises four species found in Asia, while ''P ...

References

{{Taxonbar, from=Q56328084 Arctocyonia Condylarths Paleocene genus extinctions Paleocene mammals of North America Fossil taxa described in 1885 Taxa named by Edward Drinker Cope Prehistoric placental genera