The Tiffanian North American Stage on the geologic timescale, is a North American faunal stage within the North American Land Mammal Ages chronology (NALMA). It occupies part of the Paleocene epoch, spanning an interval from about 60,900,000 to 57,500,000 years Before Present, lasting .[1][2]

The Tiffanian overlaps with part of the Selandian (Middle Paleocene) and Thanetian (Late Paleocene), which are stages on the global timescale. In regards to NALMA, the Tiffanian is preceded by the Torrejonian and followed by the Clarkforkian NALMA stages.[3]

Substages

The Tiffanian is considered to contain the following six substages, defined by a succession of species within Plesiadapis, a genus of plesiadapiforms (primate relatives):[3]

  • Tiffanian 1 (Ti1): The oldest substage, starting at the first appearance of P. praecursor and ending at the first appearance of P. anceps.
  • Tiffanian 2 (Ti2): Starting at the first appearance of P. anceps and ending at the first appearance of P. rex.
  • Tiffanian 3 (Ti3): Starting at the first appearance of P. rex and ending at the first appearance of P. churchilli.
  • Tiffanian 4 (Ti4): Starting at the first appearance of P. churchilli and ending at the first appearance of P. simonsi.
  • Tiffanian 5 (Ti5): Starting at the first appearance of P. simonsi and ending at the first appearance of P. gingerichi.
  • Tiffanian 6 (Ti6): Starting at the first appearance of P. gingerichi and ending at the first appearance of rodents in North America.

Mammal fauna

Early dinoceratans (large herbivores) and arctostylopids (small herbivores) immigrated from Asia to North America in the later part of the Tiffanian. Eulipotyphlans (shrew relatives) and plesiadapiforms (primate relatives) diversify, with Plesiadapis, Chiromyoides, microsyopids, and micromomyids joining the primate-like fauna. Carnivorous oxyaenids appear in the Tiffanian, though they were rare compared to later stages. Among bulky herbivores, new species of phenacodonts and pantodonts reached far larger sizes than their predecessors.[3]

Some archaic ungulates of the early-middle Paleocene, such as periptychids and mioclaenids, diminish and make their last appearance in North America during the Tiffanian.[3]

Notable mammals

Sources:[3][4][5][6]

Multituberculata - an extinct group of rodent-like non-therian mammals

Metatheria - marsupial-like mammals

Primatomorpha - primates and relatives, most of which are considered plesiadapiforms.

Eulipotyphla - insectivorous mammals, relatives of moles and shrews

Pantodonta - an extinct group of herbivorous mammals

Ferae - carnivorans (the group containing most living carnivorous mammals) and their relatives

"Condylarthra" - a broad category of archaic herbivorous or omnivorous mammals, including possible ancestors to various ungulates (hoofed mammals)

Dinocerata / Uintatheria - an extinct group of large, herbivorous hoofed mammals with tusks and horns

Mesonychia - an extinct group of carnivorous hoofed mammals

Other mammals - extinct groups with unclear relationships to modern mammals

Formations

The Tiffanian is named after the "Tiffany beds" near Tiffany, Colorado. These layers are now known as the Animas Formation.[3]

References

  1. ^ Barnosky, A. D.; Holmes, M.; Kircholtes, R.; Lindsey, E.; Maguire, K. C.; Poust, A. W.; Stegner, M. A.; Sunseri, J.; Swartz, B.; Swift, J.; Villavicencio, N. A. (2014). "Prelude to the Anthropocene: Two new North American land mammal ages (NALMAs)". The Anthropocene Review. 1 (3): 225–242. doi:10.1177/2053019614547433. S2CID 128697655
  2. ^ Anemone, Robert L.; Jones, Matthew F.; Van Regenmorter, John; Beard, K. Christopher (2024-05-03). "A latest Paleocene mammal fauna from the Great Divide Basin in southern Wyoming and a revised biozonation of the Clarkforkian land mammal age". Journal of Vertebrate Paleontology. 44 (3). doi:10.1080/02724634.2024.2424139. ISSN 0272-4634
  3. ^ Lofgren, Donald L.; Lillegraven, Jason A.; Clemens, William A.; Gingerich, Philip D.; Williamson, Thomas E. (2004), "3. Paleocene Biochronology: The Puercan Through Clarkforkian Land Mammal Ages", Late Cretaceous and Cenozoic Mammals of North America, Woodburne, Michael O. (ed.), Columbia University Press, pp. 43–105, doi:10.7312/wood13040-005. ISBN 978-0-231-13040-0. JSTOR 10.7312/wood13040.9, retrieved 2026-04-07
  4. ^ Secord, Ross (2008). "The Tiffanian Land-Mammal Age (Middle and Late Paleocene) In The Northern Bighorn Basin, Wyoming". Papers on Paleontology. No. 35. hdl:2027.42/61362
  5. ^ Gunnell, Gregg F. (1994-03-31). "Paleocene mammals and faunal analysis of the Chappo Type Locality (Tiffanian), Green River Basin, Wyoming". Journal of Vertebrate Paleontology. 14 (1): 81–104. doi:10.1080/02724634.1994.10011540. ISSN 0272-4634
  6. ^ Gazin, Charles Lewis (1956). "Paleocene mammalian faunas of the Bison Basin in south-central Wyoming". Smithsonian Miscellaneous Collections. 131: 1–57.
  7. ^ Burger, Benjamin John (2007). "A New Late Paleocene Vertebrate Fauna from the Ohio Creek Formation of Western Colorado". The Mountain Geologist. 44 (3): 141-150.
  8. ^ Sweedler, Rory E.; Rust, Kathleen L.; Beard, K. Christopher (2025-12-31). "Late Paleocene (Tiffanian) Mammalia from the Titanoides Locality, Bison Basin, Wyoming: Revised Biostratigraphic Age and Paleobiogeographic Implications". Annals of Carnegie Museum. 91 (3). doi:10.2992/007.091.0303. ISSN 0097-4463