A new taeniolabidoid multituberculate (Mammalia) from the middle Puercan of the Nacimiento Formation, New Mexico, and a revision of taeniolabidoid systematics and phylogeny. (5th October 2015)

• Record Type: Journal Article
• Authors: Williamson, Thomas E.; Brusatte, Stephen L.; Secord, Ross; Shelley, Sarah
• Is Part Of: Zoological journal of the Linnean Society. Volume 177:Number 1(2016:May)
• Page Start: 183
• Page End: 208
• Publication Date: 2015-10-05
• Subjects: body size -- dispersal -- ecological recovery -- mammalian radiation -- multituberculata -- palaeobiogeography -- Palaeocene -- San Juan Basin -- Taeniolabididae -- Taeniolabidoidea; Zoology -- Periodicals; 590
• DOI: 10.1111/zoj.12336
• Languages: English
• ISSNs: 0024-4082

Abstract

Abstract : Multituberculates were amongst the most abundant and taxonomically diverse mammals of the late Mesozoic and the Palaeocene, reaching their zenith in diversity and body size in the Palaeocene. Taeniolabidoidea, the topic of this paper, includes the largest known multituberculates, which possess highly complex cheek teeth adapted for herbivory. A new specimen from the early Palaeocene (middle Puercan; biochron Pu2) of the Nacimiento Formation, New Mexico represents a new large‐bodied taeniolabidoid genus and species, K imbetopsalis simmonsae . A phylogenetic analysis to examine the relationships within Taeniolabidoidea that includes new information from K imbetopsalis gen. et sp. nov. and gen. nov. and from new specimens of C atopsalis fissidens, first described here, and data from all other described North American and Asian taeniolabidoids. This analysis indicates that C atopsalis is nonmonophyletic and justifies our transfer of the basal‐most taeniolabidoid ' C atopsalis ' joyneri to a new genus, V alenopsalis . K imbetopsalis and T aeniolabis form a clade (Taeniolabididae), as do the Asian L ambdopsalis, S phenopsalis, and possibly also P rionessus (Lambdopsalidae). Taeniolabidoids underwent a modest taxonomic radiation during the early Palaeocene of North America and underwent a dramatic increase in body size, with T aeniolabis taoensis possibly exceeding 100 kg. Taeniolabidoids appear to have gone extinct in North America by the late Palaeocene but the appearance of lambdopsalids in the late Palaeocene of Asia suggests that they dispersed from North America in the early to middle Palaeocene.