Taeniolabis

Description

Taeniolabis is a member of the Taeniolabidoidea, a superfamily of multituberculates that are known for their highly derived teeth, and a short wide snout with a blocky head. The teeth modifications were likely an adaptation for herbivory that may have resulted from rapid diversification of angiosperms at the very end of the Cretaceous, which would thus have created opportunities for novel specialization in herbivores. T. taoensis possessed an elongate, gently curved cochlear canal and an enlarged vestibule. It is the largest known multituberculate, as well as the largest allotherian mammal, with T. taoensis weighing up to 34 kg. Species under this genus have been known under other names. Taeniolabis taoensis is found frequently enough and in a very limited time range that it can be used as an index fossil for the Puercan faunal stage within Danian aged fossil deposits.

Taxonomy

History

It is within the suborder of Cimolodonta and is a member of the superfamily Taeniolabidoidea. The genus was named by Edward Drinker Cope in 1882. Species have also been placed with the genera Catopsalis and Polymastodon.

Species

• Taeniolabis lamberti was named by Nancy Simmons in 1987. It has been found in the Danian aged Tullock Formation of Montana. It is not quite as large as T. taoensis, but still a hefty size for a multituberculate, weighing around 11 kg.

• Taeniolabis taoensis was originally named Taeniolabis sulcatus by Cope in 1882 as the type species of the genus. It was later renamed as T. taoensis. Known fossils date to approximately 64 million years of age. They are found in Danian aged deposits of the Nacimiento Formation of New Mexico, the Ravenscrag Formation of Saskatchewan and the Denver Formation of Colorado. This species likely had a roughly16 cm long skull and had an average body mass of 22.7 kg, which is approximately the size of a modern beaver. The species was once considered to have had a body mass of up to 100 kg and sized like a sheep or larger by extrapolating body size on the basis of their huge teeth. However, improved analyses and the realization that the teeth were extraordinarily robust due to herbivory rather has generally disproved that.

Notes

References

• {{cite journal |last1=Cope | first1=E.D. | title=Geology and Paleontology, A new genus of Taeniodonta| date=1882|journal=American Naturalist

• {{cite web |last1=Dykes |first1=Trevor |title=Mesozoic Mammals; Eucosmodontidae, Microcosmodontidae and Taeniolabidoidea, an internet directory | url-status=dead|archive-url=https://web.archive.org/web/20120716204423/http://home.arcor.de/ktdykes/taenio.htm |archive-date=16 July 2012 |url=http://home.arcor.de/ktdykes/taenio.htm}}

• {{cite journal|last1=Simmons|first1=Nancy B. | title= A Revision of Taeniolabis (Mammalia: Multituberculata), with a New Species from the Puercan of Eastern Montana Journal of Paleontology|volume=61|issue=4|date= 1987|pages=794–808|doi=10.1017/S0022336000029140 |bibcode=1987JPal...61..794S |s2cid=133216712 }}

• {{cite journal |last1=Wilson | first1=Gregory P. |last2=Evans | first2=Alistair R.| last3=Corfe| first3=Ian J.|last4=Smits|first4=Peter D.|last5=Fortelius|first5=Mikael|last6=Jernvall|first6=Jukka

References

1. Simmons 1987, pp 802-804
2. Palmer 1904, p 659. From Greek
3. Kielan-Jawoworska and Hurum, 2001
4. Wilson et al, 2012, pp 458-459
5. (13 December 2021). "New Skull Material of Taeniolabis taoensis (Multituberculata, Taeniolabididae) from the Early Paleocene (Danian) of the Denver Basin, Colorado". [[Journal of Mammalian Evolution]].
6. Rose 2006, p 60
7. Krause et al 2021, p 1085
8. (October 2019). "Exceptional continental record of biotic recovery after the Cretaceous–Paleogene mass extinction". Science.
9. Palebiology Database
10. Simmons 1987
11. Krause et al 2021, p 1085
12. Cope 1882, pg 604-605
13. Simmons 1987, pp 802-804
14. Wilson, G. P.. (2013). "Mammals across the K/Pg boundary in northeastern Montana, U.S.A.: Dental morphology and body-size patterns reveal extinction selectivity and immigrant-fueled ecospace filling". Paleobiology.
15. Cope 1882, pg 604-605
16. Wilson et al, 2012 Supplemental Table 5
17. Krause et al 2021, p 1086
18. Cope 1882, p 605
19. Krause et al 2021, p 1085 with lengthy discussion about estimates of size
20. Wilson et al, 2012 Supplemental Table 5