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Windows on the evolution of Picrodus (Plesiadapiformes: Primates): Morphology and relationships of a species complex from the Paleocene of Alberta

Published online by Cambridge University Press:  11 August 2017

Craig S. Scott
Affiliation:
Laboratory for Vertebrate Paleontology, Department of Biological Sciences, University of Alberta, Edmonton T6G 2E9, Canada,
Richard C. Fox
Affiliation:
Laboratory for Vertebrate Paleontology, Department of Biological Sciences, University of Alberta, Edmonton T6G 2E9, Canada,

Abstract

Since 1908, the peculiar North American primate Picrodus Douglass, 1908 (Picrodontidae; Plesiadapiformes) has been thought to contain only a single species, P. silberlingi Douglass, 1908, of late Paleocene age. However, new collections from the Paskapoo Formation, Alberta, Canada, reveal that instead a rich complex of Picrodus species lived during the Paleocene. Three of these, Picrodus calgariensis, P. canpacius, and P. lepidus, are described herein as new. Others, represented by more fragmentary specimens from Canada and the United States, are included in this paper, but are not named. P. calgariensis, from Who Nose? (late Torrejonian), Calgary, is the most primitive known species of Picrodus, having molars with little crenulation of the enamel. P. canpacius, from Cochrane 2 (earliest Tiffanian), northwest of Calgary, most resembles P. silberlingi sensu stricto, but differs in P4 structure, denser enamel crenulation, and weaker molar cusps. P. lepidus, from DW-2 (middle Tiffanian), near Red Deer, is the most advanced, having, for example, a two-rooted P4, tiny p3, and single-rooted p4. At least two of these species also occur in the United States, documented by fossils referred to P. silberlingi by previous workers. Dental evolution within Picrodus seems marked by several trends, including increase in size of i1, simplification of P4, reduction of molar cusps and crests, enlargement of the horizontal occlusal surfaces of the molars, and greater crenulation of enamel. From present knowledge, Zanycteris paleocenus Matthew, 1917 is dentally more primitive than Picrodus, Draconodus Tomida, 1982 is a valid genus, and picrodontids probably originated from “purgatoriid-grade” plesiadapiforms in earliest Paleocene time.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

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References

Archibald, J. D., Gingerich, P. D., Lindsay, E. H., Clemens, W. A., Krause, D. W., and Rose, K. D. 1987. First North American land mammal ages of the Cenozoic Era, p. 2476. In Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkeley.Google Scholar
Beard, K. C. 1993. Phylogenetic systematics of the Primatomorpha, with special reference to Dermoptera, p. 129150. In Szalay, F. S., Novacek, M. J., and McKenna, M. C. (eds.), Mammal Phylogeny: Placentals. Springer-Verlag, New York.CrossRefGoogle Scholar
Beard, K. C., and Wang, J. 1995. The first Asian plesiadapoids (Mammalia: Primatomorpha). Annals of Carnegie Museum, 64:133.CrossRefGoogle Scholar
Bloch, J. I., and Boyer, D. M. 2002. Grasping primate origins. Science, 298:16061610.CrossRefGoogle ScholarPubMed
Douglass, E. 1908. Vertebrate fossils from the Fort Union beds. Annals of Carnegie Museum, 5:1126.CrossRefGoogle Scholar
Fox, R. C. 1990. The succession of Paleocene mammals in western Canada, p. 5170. In Bown, T. M. and Rose, K. D. (eds.), Dawn of the Age of Mammals in the Northern Part of the Rocky Mountain Interior, North America. Geological Society of America Special Paper, 243.Google Scholar
Fox, R. C. 1994. The primitive dental formula of the Carpolestidae (Plesiadapiformes, Mammalia) and its phylogenetic implications. Journal of Vertebrate Paleontology, 13 (for 1993):516524.CrossRefGoogle Scholar
Gervais, P. 1877. Enumeration du quelques ossements d'animaux vertebres recueillis aux environs de Reims par M. Lemoine. Journal de Zoologie (Paris), 6:7479.Google Scholar
Gingerich, P. D. 1982. Paleocene “Meniscotherium semicingulatum“ and the first appearance of Meniscotheriidae (Condylarthra) in North America. Journal of Mammalogy, 58:488491.CrossRefGoogle Scholar
Gingerich, P. D., Houde, P., and Krause, D. W. 1983. A new earliest Tiffanian (late Paleocene) mammalian fauna from the Bangtail Plateau, western Crazy Mountain Basin, Montana. Journal of Paleontology, 57:957970.Google Scholar
Gunnell, G. F. 1989. Evolutionary history of Microsyopoidea (Mammalia, ?Primates) and the relationship between Plesiadapiformes and Primates. University of Michigan Papers on Paleontology, 27:1157.Google Scholar
Gunnell, G. F. 1994. Paleocene mammals and faunal analysis of the Chappo Type Locality (Tiffanian), Green River Basin, Wyoming. Journal of Vertebrate Paleontology, 14:81104.CrossRefGoogle Scholar
Hartman, J. E. 1986. Paleontology and biostratigraphy of lower part of Polecat Bench Formation, southern Bighorn Basin, Wyoming. Contributions to Geology, University of Wyoming, 24:1163.Google Scholar
Johnson, G. D., Murry, P. A., and Storer, J. E. 1994. Recovery of vertebrate microfossils. Proceedings of the South Dakota Academy of Science, 73:211230.Google Scholar
Krause, D. W. 1978. Paleocene primates from western Canada. Canadian Journal of Earth Sciences, 15:12501271.CrossRefGoogle Scholar
Lerbekmo, J. F., and Sweet, A. R. 2000. Magnetostratigraphy and biostratigraphy of the continental Paleocene of the Calgary area, southwestern Alberta. Bulletin of Canadian Petroleum Geology, 48:285306.CrossRefGoogle Scholar
Linnaeus, C. 1758. Systema naturae per regna tria naturae, secundum classes, ordines, genera, species cum characteribus, differentiis, synonymis locis (editio decima, reformata). Volume 1. Laurentii Salvii, Stockholm, 824 p.Google Scholar
Luckett, W. P. 1993. An ontogenetic assessment of dental homologies in therian mammals, p. 182204. In Szalay, F. S., Novacek, M. J., and McKenna, M. C. (eds.), Mammal Phylogeny: Mesozoic Differentiation, Multituberculates, Monotremes, Early Therians, and Marsupials. Springer-Verlag, New York.CrossRefGoogle Scholar
Macdonald, T. E. 1996. Late Paleocene (Tiffanian) mammal-bearing localities in superposition, from near Drumheller, Alberta. Unpublished , , 248 p.Google Scholar
Matthew, W. D. 1915. Pt. IV.—Entelonychia, Primates, Insectivora (part), p. 429483. In Matthew, W. D. and Granger, W. (eds.), A revision of the lower Eocene Wasatch and Wind River faunas. Bulletin of the American Museum of Natural History, 34.Google Scholar
Matthew, W. D. 1917. A Paleocene bat. Bulletin of the American Museum of Natural History, 37:569571.Google Scholar
Mcgrew, P. O., and Patterson, B. 1962. A picrodontid insectivore(?) from the Paleocene of Wyoming. Breviora, 175:19.Google Scholar
McKenna, M. C. 1980. Late Cretaceous and Early Tertiary vertebrate paleontological reconnaissance, Togwotee Pass area, northwestern Wyoming, p. 321343. In Jacobs, L. L. (ed.), Aspects of Vertebrate History. Museum of Northern Arizona Press, Flagstaff.Google Scholar
Novacek, M. J. 1986. The skull of leptictid insectivorans and the higher-level classification of eutherian mammals. Bulletin of the American Museum of Natural History, 183:1111.Google Scholar
Romer, A. S. 1966. Vertebrate Paleontology (third edition). University of Chicago Press, Chicago, 468 p.Google Scholar
Russell, D. E. 1964. Les mammifères Paléocène d'Europe. Mémoires du Muséum National d'Histoire Naturelle, n. s., 13:1324.Google Scholar
Schiebout, J. A. 1974. Vertebrate paleontology and paleoecology of Paleocene Black Peaks Formation, Big Bend National Park, Texas. Bulletin of the Texas Memorial Museum, 24:188.Google Scholar
Schwartz, J. H., and Krishtalka, L. 1977. Revision of Picrodontidae (Primates, Plesiadapiformes): Dental homologies and relationships. Annals of Carnegie Museum, 46:5570.CrossRefGoogle Scholar
Scott, C. S. 2003. Late Torrejonian (middle Paleocene) mammals from south central Alberta. Journal of Paleontology, 77:745768.2.0.CO;2>CrossRefGoogle Scholar
Scott, C. S., Fox, R. C., and Youzwyshyn, G. P. 2002. New earliest Tiffanian (late Paleocene) mammals from Cochrane 2, southwestern Alberta, Canada. Acta Palaeontologica Polonica, 47:691704.Google Scholar
Silcox, M. T. 2001. A phylogenetic analysis of Plesiadapiformes and their relationship to Euprimates and other archontans. Unpublished Ph.D. dissertation, The Johns Hopkins University, Baltimore, Maryland, 728 p.Google Scholar
Silcox, M. T. 2003. New discoveries on the middle ear anatomy of Ignacius graybullianus (Paromomyidae, Primates) from ultra high resolution X-ray computed tomography. Journal of Human Evolution, 44:7386.CrossRefGoogle ScholarPubMed
Silcox, M. T., and Gunnell, G. F. In press. Plesiadapiformes. In Janis, C. M., Gunnell, G. F., and Uhen, M. D. (eds.), Evolution of Tertiary Mammals of North America. Volume 2. Marine Mammals and Smaller Terrestrial Mammals. Cambridge University Press.Google Scholar
Simons, E. L. 1972. Primate Evolution: An Introduction to Man's Place in Nature. Macmillan, New York, 322 p.Google Scholar
Simpson, G. G. 1935. The Tiffany fauna, upper Paleocene. I.—Multituberculata, Marsupialia, Insectivora, and ?Chiroptera. American Museum Novitates, 795:119.Google Scholar
Simpson, G. G. 1937. The Fort Union of the Crazy Mountain Field, Montana, and its mammalian faunas. Bulletin of the United States National Museum, 169:1287.CrossRefGoogle Scholar
Simpson, G. G. 1940. Studies on the earliest primates. Bulletin of the American Museum of Natural History, 77:185212.Google Scholar
Szalay, F. S. 1968. The Picrodontidae, a family of early primates. American Museum Novitates, 2329:155.Google Scholar
Szalay, F. S., and Delson, E. 1979. Evolutionary History of the Primates. Academic Press, New York, 580 p.Google Scholar
Szalay, F. S., Rosenberger, A. L., and Dagosto, M. 1987. Diagnosis and differentiation of the order Primates. Yearbook of Physical Anthropology, 30:75105.CrossRefGoogle Scholar
Tomida, Y. 1982. A new genus of picrodontid primate from the Paleocene of Utah. Folia Primatologica, 37:3743.CrossRefGoogle ScholarPubMed
Tomida, Y. 1994. Phylogenetic reconstruction of mammals based on cheek tooth morphology. Honyuri Kagaku, 34:1929.Google Scholar
Van Valen, L. 1994. The origin of the plesiadapid primates and the nature of Purgatorius . Evolutionary Monographs, 15:179.Google Scholar
Van Valen, L., and Sloan, R. E. 1965. The earliest primates. Science, 150:743745.CrossRefGoogle ScholarPubMed
Williams, J. A. 1985. Morphology and variation in the posterior dentition of Picrodus silberlingi (Picrodontidae). Folia Primatologica, 45:4858.CrossRefGoogle ScholarPubMed
Youzwyshyn, G. P. 1988. Paleocene mammals from near Cochrane, Alberta. Unpublished , , 484 p.Google Scholar