Machaeroides, Palaeogale, Onychodectes and Conoryctella

Machaeroides eothen (Matthew 1909; Eocene, 56mya) has been difficult to nest, with some experts labeling this genus close to Oxyaena, a marsupial creodont. Here Machaeroides nests with Protictitherium and Daphoenus based on nmnhpaleobiology_338172 in the collection of the Smithsonian.

Palaeogale minuta (aka Bunaelurus, von Meyer 1846, Cope 1873, Matthew 1902, Late Eocene to Early Miocene) was considered a small mustelid (mink). Wikipedia reports 'the ancestry of Palaeogale remains enigmatic.' Here Palaeogale nests with Machaeroides, perhaps as a juvenile based on size, proprotions and only 2 molars.

Onychodectes tisonensis (Cope 1888, earliest Paleocene, 64mya) was considered a taeniodont, but here nests basal to Carpolestes and the Rodentia + Multituberculata, all derived from the tree shrews, and Ptilocercus, as well as Microysops.

Conoryctella dragonensis (Gazin 1939; Paleocene; holotype USNM 15704) is a traditional taeniodont, but here nests with Onychodectes, sharing most of its traits. Traditionally this genus is identified by its teeth, which tend to converge in Mammalia, rather than in a cladogram which tests all available traits. Note the flat to cup-shaped molars and the long premaxilla.

Cope ED 1876. On the Taeniodonta, a new group of Eocene Mammalia. Proceedings of the Academy of Natural Science. Philadelphia 28:39.

Cope ED 1888. The vertebrate fauna of the Puerco epoch. Am. Nat. 22:161-63.

Cope ED 1888. Synopsis of the vertebrate fauna of the Puerco series. Trans. Am. Philos. Soc. n.s., 16:298-361.

Gazin CL 1939. A further contribution to the Dragon Paleocene fauna of central Utah. Journal of Washington Academy of Sciences 29(7):273-286.

Matthew WD 1902. On the skull of Bunaelurus, a musteline from the White River Oligocene. Bulletin of the AMNH 16. [Palaeogale]

Matthew WD 1909. The Carnivora and Insectivora of the Bridger Basin, middle Eocene. Memoirs of the American Museum of Natural History 9:289-567.

Schoch RM and Lucas SG 1981. A new species of Conoryctella (Mammalia: Taeniodonta) from the Paleocene of the San Juan Basin, New Mexico, and a revision of the genus. Postilla 185: 23pp.

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wiki/Palaeogale
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