Paulchoffatia, Ignacius, Niptomomys and Carpolestes

Paulchoffatia delgadoi (aka: Paulchoffia; Kühne 1961; Latest Jurassic, 160 mya; 2.5 cm skull length) was originally and is here considered an early member of the Multituberculata. Carpolestes, an arboral rodent cousin is basal.

Paulchoffatia had a massive jaw with similar sized teeth other than the elongate incisors. Five specimens are known, all mandibles.

Below are taxa tested in the LRT that are in the lineage of multituberculates.

Niptomomys doreenae (McKenna 1960, White et al 2023, Late Paleocene, USNM 530198) was originally considered a primate, but here nests with Microsyops far from the primates, somewhat close to Tupaia and other tree shrews.

Carpolestes snigridens (Simpson 1928; late Paleocene, 58 mya; ~20cm in length) was traditionally considered an outgroup to the Primates, but here nests as a primate-like rodent between Ignacius and multituberculates like Paulchoffatia.

Like Notharctus, Carpolestes had a thumb-like pollex and hallux and was a long-limbed arboreal herbivore. Note the large last lower premolar, a precursor to the otherwise unique multituberculate tooth (see below) which oddly does not appear in Paulchoffatia.

Ignacius frugivorus (formerly Phenacolemur; Matthew and Granger 1921; Paleocene) was originally based on upper jaw with teeth. It is traditionally and here considered a plesiadapiform, close to Plesiadapis, but traditionally both were considered basal primates. Here both nest within Glires, between the mouse/squirrel clade and the multituberculate clade.

Bloch JI, Fishe DC, Rose KD and Gingerich PD 2001. Stratocladistic analysis of Paleocene Carpolestidae (Mammalia, Plesiadapiformes) with description of a new late Tiffanian genus. Journal of Vertebrate Paleontology. 21 (1): 119–131.

Boyer DM and Bloch JI 2008. Evaluating the Mitten-Gliding Hypothesis for Paromomyidae and Micromomyidae (Mammalia, “Plesiadapiformes”) Using Comparative Functional Morphology of New Paleogene Skeletons. Chapter 11 in Sargis EJ and Dagosto M (eds.), Mammalian Evolutionary Morphology: A Tribute to Frederick S. Szalay, 233–284.
Springer Science + Business Media BV

Cope ED 1882. A new genus of Taeniodonta. American Naturalist XVI, p. 604-605.

Kühne WB 1961. Eine Mammaliafauna aus dem Kimmeridge Portugals. Neues Jahrbuch für Geologie und Paläontologie, Monatshefte 1961:374-381.

Matthew WD and Grange W 1921. New genera of Paleocene mammals. American Museum Novitates 13:1-7

McKenna MC 1960. Fossil Mammalia from the early Wasatchian Foru Mile fauna, Eocene of northwest Colorado. U of California Publications geological sciences 37:1–130.

Simpson G G 1928. A new mammalian fauna from the Fort Union of southern Montana. American Museum Novitates 297:1-15.

White CL, Bloch JI, Morse PE and Silcox MT 2021. Virtual endocast of late Paleocene Niptomomys (Microsyopidae, Euarchonta) and early primate brain evolution. Journal of Human Evolution 175: 103303

wik/Paulchoffatia
wiki/Carpolestes
wiki/Niptomomys - not yet posted
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