Saimiri fieldsi

Saimiri fieldsi Temporal range: Middle Miocene (Laventan) ~]
Conservation status
Extinct
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Primates
Suborder:	Haplorhini
Infraorder:	Simiiformes
Family:	Cebidae
Genus:	Saimiri
Species:	†S. fieldsi
Binomial name
†Saimiri fieldsi Stirton 1951
Synonyms
Neosaimiri fieldsi Stirton 1951

Saimiri fieldsi is an extinct species of New World monkey in the genus Saimiri (squirrel monkeys) from the Middle Miocene (Laventan in the South American land mammal ages; 13.8 to 11.8 Ma). Its remains have been found at the Konzentrat-Lagerstätte of La Venta in the Honda Group of Colombia.

Description

More than 200 fossil specimens of Saimiri fieldsi, formerly described as Neosaimiri fieldsi, were recovered from the Middle Miocene Villavieja Formation, that has been dated to the Laventan, about 13 to 12 Ma, during fieldwork in 1989 and 1990. The holotype of Saimiri which was recovered in 1949, is an incomplete mandible and dentition, while later materials include not only lower but also upper dentition and deciduous teeth.

The fossils were differentiated from Saimiri in the proportions of tooth series, with smaller incisors and larger molars; in the structure of the P4 hypocone; and in the morphology of M1-2, which shows strong polymorphism. Also the species has been described as more robust than the extant Saimiri. This led researchers to identify an independent genus, Neosaimiri, as a Middle Miocene ancestor of Saimiri. Laventiana annectens, which was recovered at the same location in 1988, has been concluded to be a junior synonym of Neosaimiri, placed later in the same genus as Saimiri annectens.

The lower molars of the fossil Saimiri resemble those of Dolichocebus, from Argentina. An estimated body mass of 768 to 840 grams (1.693 to 1.852 lb) has been suggested for Saimiri fieldsi.

Evolution

See also: Evolution of primates

The evolutionary split in New World monkeys between Cebus and Saimiri has been estimated at 16.7 Ma.

Habitat

See also: Honda Group, Colombia § Paleoclimate and vegetation

The La Venta Lagerstätte of the Honda Group, and more precisely the "Monkey Beds", are the richest site for fossil primates in South America. It has been argued that the monkeys of the Honda Group were living in habitat that was in contact with the Amazon and Orinoco Basins, and that La Venta itself was probably seasonally dry forest. Other fossil New World primates uncovered from the same locality are Aotus dindensis, Cebupithecia, Mohanamico and Stirtonia tatacoensis.

See also

• List of primates of Colombia
• Lagonimico

References

Bibliography

• Defler, Thomas (2004), Historia natural de los primates colombianos (PDF), Universidad Nacional de Colombia, pp. 1–613, retrieved 2017-09-24
• Luchterhand, Kubet; Kay, Richard F.; Madden, Richard H. (1986), "Mohanamico hershkovitzi, gen. et sp. nov., un primate du Miocene moyen d' Amerique du Sud", Comptes rendus de l'Académie des sciences, 303: 1753–1758, retrieved 2017-09-24
• Lynch Alfaro, Jessica W.; Cortés Ortiz, Liliana; Di Fiore, Anthony; Boubli, Jean P. (2015), "Special issue: Comparative biogeography of Neotropical primates" (PDF), Molecular Phylogenetics and Evolution, 82: 518–529, Bibcode:2015MolPE..82..518L, doi:10.1016/j.ympev.2014.09.027, PMID 25451803, retrieved 2017-09-24
• Pérez, S. Iván; Tejedor, Marcelo F.; Novo, Nelson M.; Aristide, Leandro (2013), "Divergence Times and the Evolutionary Radiation of New World Monkeys (Platyrrhini, Primates): An Analysis of Fossil and Molecular Data", PLOS One, 8 (6): 1–16, Bibcode:2013PLoSO...868029P, doi:10.1371/journal.pone.0068029, PMC 3694915, PMID 23826358
• Rosenberger, Alfred L.; Hartwig, Walter Carl (2001), "New World Monkeys" (PDF), Encyclopedia of Life Sciences: 1–4, retrieved 2017-09-24
• Rosenberger, A.L.; Hartwig, W.C.; Takai, M.; Setoguchi, T.; Shigehara, N. (1991), "Dental variability in Saimiri and the taxonomic status of Neosaimiri fieldsi, an early squirrel monkey from La Venta, Colombia" (PDF), International Journal of Primatology, 12 (3): 291–301, doi:10.1007/BF02547590, retrieved 2017-09-24
• Setoguchi, Takeshi; Shigehara, Nobuo; Rosenberger, Alfred L.; Cadena G, Alberto (1986), "Primate fauna from the Miocene La Venta, in the Tatacoa Desert, Department of Huila, Colombia" (PDF), Caldasia, XV: 761–773, retrieved 2017-09-24
• Setoguchi, Takeshi; Shigehara, Nobuo; Rosenberger, Alfred L.; Cadena G, Alberto (1986), "Primate fauna from the Miocene La Venta, in the Tatacoa Desert, Department of Huila, Colombia" (PDF), Caldasia, XV: 761–773, retrieved 2017-09-24
• Silvestro, Daniele; Tejedor, Marcelo F.; Serrano Serrano, Martha L.; Loiseau, Oriane; Rossier, Victor; Rolland, Jonathan; Zizka, Alexander; Antonelli, Alexandre; Salamin, Nicolas (2017), "Evolutionary history of New World monkeys revealed by molecular and fossil data" (PDF), BioRxiv: 1–32, retrieved 2017-09-24
• Takai, Masanaru; Anaya, Federico; Suzuki, Hisashi; Shigehara, Nobuo; Setoguchi, Takeshi (2001), "A New Platyrrhine from the Middle Miocene of La Venta, Colombia, and the Phyletic Position of Callicebinae", Anthropological Science, Tokyo, 109 (4): 289–307, doi:10.1537/ase.109.289, retrieved 2017-09-24
• Takai, Masanaru (1994), "New specimens of Neosaimiri fieldsi from La Venta, Colombia: a middle Miocene ancestor of the living squirrel monkeys", Journal of Human Evolution, 27 (4): 329–360, Bibcode:1994JHumE..27..329T, doi:10.1006/jhev.1994.1049
• Tejedor, Marcelo F (2013), "Sistemática, evolución y paleobiogeografía de los primates Platyrrhini" (PDF), Revista del Museo de La Plata, 20: 20–39, retrieved 2017-09-24
• Wheeler, Brandon (2010), "Community ecology of the Middle Miocene primates of La Venta, Colombia: the relationship between ecological diversity, divergence time, and phylogenetic richness", Primates, 51 (2): 131–138, doi:10.1007/s10329-009-0181-y, PMID 20037832, retrieved 2017-09-24

Further reading

• Fleagle, John G.; Rosenberger, Alfred L. (2013), The Platyrrhine Fossil Record, Elsevier, pp. 1–256, ISBN 9781483267074, retrieved 2017-10-21
• Hartwig, W.C.; Meldrum, D.J. (2002), The Primate Fossil Record - Miocene platyrrhines of the northern Neotropics, Cambridge University Press, pp. 175–188, ISBN 978-0-521-08141-2, retrieved 2017-09-24