Ectoganus, Schowalteria, Stylinodon, Wortmania and Psittacotherium

Vertebrata

Fish

Tetrapoda

Reptilia/Amniota

Archosauromorpha

Basal Archosauromorpha

Mammalia

Terrestrial Younginiformes

Marine Younginiformes

Lepidosauromorpha

Cephalerpeton clade

Captorhinidae

Milleretta Limnoscelis clade

Bolosaurus Diadectes clade

Turtle Pareiasaur clade

Fenestrasauria • Pterosauria

Protosquamata

Squamata

Psittacotherium manus pes compared to Elephas

Palaeomastdon and Psittacotherium skulls to scale

Psittacotherium (Cope 1882; Paleocene) preserves post-crania and was originally considered a tillodont, then a taeniodont. Here it nests with Stylinodon and kin basal to elephants.

Ectoganus copei (Schoch 1981; USNM 12714; early Eocene) is a sister to Stylinodon with a longer, lower skull, two upper incisors and a kinked maxilla.

Stylinodon mirus (Marsh 1874; middle Eocene, 45 mya) was originally considered a taeniodont, perhaps derived from the basal phenacodont, Onychodectes. Here it nests with Mustela the living mink, Gulo the living wolverine and Ursus the living polar bear among the Carnivora.

The largest anterior teeth were canines. The peg-like molars also continued growing throughout life. There were twice as many molars (4), each with a single root, as in the two double rooted molars of the mink. The teeth continued growing throughout life, as in edentates like Glyptodon. Large claws indicate that digging remained part of its lifestyle.

Schowalteria clemensi (Fox and Naylor 2003; Maastrichtian, Cretaceous, 68mya) was considered a stylinodont, taeniodont eutherian.

Wortmania (Hay 1899, Williamson and Brusatte 2013) and Psittacotherium (Cope 1882; below) are related taxa.

Cope ED 1882. A new genus of Tillodonta. The American Naturalist, 16: 156–157.

Fox RC and Naylor BG 2003. A Late Cretaceous taeniodont (Eutheria, Mammalia) from Alberta, Canada. Neues Jahrbuch für Geologie und Paläontologie. 229 (3):393–420.

Hay OP 1899. On the names of certain North American fossil vertebrates. Science 9: 593-594. doi:10.1126/science.9.225.593. PubMed: 17772698.

Linneaus C von 1761. Fauna Suecica sistens Animalia Sueciae Regni: Mammalia, Aves, Amphibia, Pisces, Insecta, Vermes. Distributa per Classes, Ordines, Genera, Species, cum Differentiis Specierum, Synonymis Auctorum, Nominibus Incolarum, Locis Natalium, Descriptionibus insectorum. Editio altera, auctior. Stockholmiae: L. Salvii, 48 + 578 pp

Marsh OC 1874. Notice of new Tertiary mammals 3. American Journal of Science. (3) 7i: 531-534.

Rook DL and Hunter JP 2013. Rooting around the eutherian family tree: the origin and relations of the Taeniodonta. Journal of Mammal Evolution. DOI 10.1007/s10914-013-9230-9

Schoch RM 1981. Revision of the middle Paleocene (Torrejonian) taeniodont (Mammalia)
Psittachotherium Cope, 1882, p. 177-85. In Lucas SG, Rigby JK, Jr., and Kues BS [eds.]. Advances in San Juan Basin paleontology. University of New Mexico Press, Albuquerque.

Schoch RM and Lucas SG 1981. The systematics of Stylinodon, an Eocene Taeniodont (Mammalia) from western North America. Journal of Vertebrate Paleontology 1(2):175-183.

Schoch RM 1983. Systematics, functional morphology and macroevolution of the extinct mammalian order Taeniodonta. Peabody Museum of Natural History Bulletin 42: 307pp. 60 figs. 65 pls.

Schoch RM 1986. Systematics, functional morphology and macroevolution of the extinct mammalian order Taeniodonta. Bulletin of the Peabody Museum of Natural History, Yale University, New Haven. 307pp.

Williamson TE and Brusatte SL 2013. New specimens of the rare Taeniodont Wortmania (Mammalia: Eutheria) from the San Juan Basin of New Mexico and comments on the phylogeny and functional morphology of “archaic” mammals. PLoS ONE 8(9): e75886. doi:10.1371/journal.pone.0075886

Wortman JL 1896. Psittacotherium, a member of a new and primitive suborder of the Edentata. Bulletin of the American Museum of Natural History 8(16):259–262.

wiki/Stylinodon
wiki/Psittacotherium
wiki/Wortmania
wiki/Schowalteria