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New cyriacotheriid pantodonts (Mammalia, Pantodonta) from the Paleocene of Alberta, Canada, and the relationships of Cyriacotheriidae

Published online by Cambridge University Press:  14 July 2015

Craig S. Scott
Craig S. Scott*
Affiliation:
Royal Tyrrell Museum of Palaeontology, P. O. Box 7500, Drumheller, Alberta, Canada T0J 0Y0
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Abstract

Cyriacotheriidae are a family of unusual small-bodied pantodonts known from the Paleocene of the Western Interior of North America. Cyriacotheriids possess a suite of dental characters similar to that of pantodonts (e.g., molar dilambdodonty, lingual molar hypoconulids), as well as several divergent features (e.g., molarized premolars, strong molar conules) that have been interpreted as “dermopteran-like.” the unusual combination of pantodont and dermopteran-like characters, combined with a limited fossil record, has made attempts at understanding the broader relationships of Cyriacotheriidae difficult. This paper reports on a new genus and two new species of cyriacotheriids from the Paleocene of Alberta, Canada, with both species significantly older than those of the only previously described cyriacotheriid, Cyriacotherium. Collectively, the dentitions of these new taxa exhibit derived characters seen in Cyriacotherium (e.g., robust molar conules, strong molar dilambdodonty) in addition to a number of plesiomorphies seen in more basal pantodonts (e.g., conspicuous molar entoconids, deep premolar ectoflexus) and, importantly, posterior premolars that are weakly molariform and non-dilambdodont. A phylogenetic analysis of the new cyriacotheriid, basal pantodonts, dermopterans, and dermopteran-like eutherians resulted in Cyriacotheriidae nesting within a monophyletic Pantodonta. the results strengthen previous hypotheses regarding the pantodont affinities of the family, and suggest that the dermopteran-like features seen in the more derived Cyriacotherium were acquired convergently. Although the discovery of new cyriacotheriids sheds light on the evolutionary history of the family, it cannot resolve the ongoing questions of pantodont origins; nonetheless, their discovery in strata of early Paleocene age indicates that significant parts of the evolutionary history of Cyriacotheriidae, and North American pantodonts more generally, have yet to be discovered.

Type
Research Article
Information
Journal of Paleontology , Volume 84 , Issue 2 , March 2010 , pp. 197 - 215
Copyright
Copyright © The Paleontological Society 

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References

Literature Cited

Archibald, J. D. and Averianov, A. O.. 2006. Late Cretaceous asioryctitherian eutherian mammals from Uzbekistan and phylogenetic analysis of Asioryctitheria. Acta Palaeontologica Polonica, 51:351–376.Google Scholar
Beard, K. C. 1998. East of Eden: Asia as an important center of taxonomic origination in mammalian evolution, p. 5–39. In Beard, K. C. and Dawson, M. R. (eds.), Dawn of the Age of Mammals in Asia. Bulletin of Carnegie Museum of Natural History, 34.Google Scholar
Boddaërt, P. 1768. Cynocephalus. Dierkundig Mengelwerk, 2:8(footnote 1).Google Scholar
Bown, T. M. and Rose, K. D.. 1979. Mimoperadectes, a new marsupial, and Worlandia, a new dermopteran, from the lower part of the Willwood Formation (early Eocene), Bighorn Basin, Wyoming. Contributions from the Museum of Paleontology, The University of Michigan, 25:89–104.Google Scholar
Bremer, K. 1988. The limits of amino acid sequence data in angiosperm phylogenetic reconstruction. Evolution, 42:795–803.CrossRefGoogle ScholarPubMed
Bremer, K. 1994. Branch support and tree stability. Cladistics, 10:295–304.CrossRefGoogle Scholar
Carpenter, J. M. 1996. Uninformative bootstrapping. Cladistics, 12:177–181.Google ScholarPubMed
Chow, M. and Wang, B.. 1979. Relationship between the pantodonts and tillodonts and a classification of the order Pantodonta. Vertebrata PalAsiatica, 17:37–48. [in Chinese with English abstract]Google Scholar
Chow, M., Chang, Y., Wang, B., and Ting, S.. 1973. New mammalian genera and species from the Paleocene of Nanhsiung, N. Kwangtung. Vertebrata PalAsiatica, 9:286–291. [in Chinese with English summary]Google Scholar
Chow, M., Chang, Y., Wang, B., and Ting, S.. 1977. Paleocene mammalian fauna from the Nanxiong Basin, Guangdong. Paleontologica Sinica, New Series C, 20:1–100. [in Chinese with English summary]Google Scholar
Clemens, W. A. 1966. Fossil mammals of the type Lance Formation, Wyoming. Part II. Marsupialia. University of California Publications in Geological Sciences, 62:1–122.Google Scholar
Clemens, W. A. and Russell, L. S.. 1965. Mammalian fossils from the Upper Edmonton Formation. University of Alberta Bulletin (Geology Series), 2:32–40.Google Scholar
Clyde, W. C., Yongsheng, T., Snell, K. E., Bowen, G. J., Ting, S., Koch, P. L., Li, Q., Wang, Y., and Meng, J.. 2008. An integrated stratigraphic record from the Paleocene of the Chijiang Basin, Jiangxi Province (China): Implications for mammalian turnover and Asian block rotations. Earth and Planetary Science Letters, 269:554–564.CrossRefGoogle Scholar
Cope, E. D. 1873. On the short-footed Ungulata of the Eocene of Wyoming. Proceedings of the American Philosophical Society, 13:38–74.Google Scholar
Cope, E. D. 1875. Systematic catalogue of Vertebrata of the Eocene of New Mexico by parties of the expedition of 1874, Chapter 12: Fossils of the Eocene period. Geographical Surveys west of the 100th Meridian, G. M. Wheeler, Corps of Engineers, U. S. Army, Washington, 4:37–282.Google Scholar
Cope, E. D. 1881. Mammalia of the Lower Eocene beds. American Naturalist, 15:337–338.Google Scholar
Cope, E. D. 1882a. Two new genera of the Puerco Eocene. American Naturalist, 16:417–418.Google Scholar
Cope, E. D. 1882b. Notes on Eocene Mammalia. American Naturalist, 16:522.Google Scholar
Cope, E. D. 1883a. The ancestor of Coryphodon. American Naturalist, 17:406–407.Google Scholar
Cope, E. D. 1883b. On the mutual relationships of the bunotherian Mammalia. Proceedings of the Academy of Natural Sciences Philadelphia, 35:77–83.Google Scholar
Demchuk, T. D. 1990. Palynostratigraphic zonation of Paleocene strata in the central and south-central Alberta Plains. Canadian Journal of Earth Sciences, 27:1263–1269.CrossRefGoogle Scholar
Demchuk, T. D. and Hills, L. V.. 1991. A re-examination of the Paskapoo Formation in the central Alberta Plains: the designation of three new members. Bulletin of Canadian Petroleum Geology, 39:270–282.Google Scholar
Ducrocq, S., Buffetaut, E., Buffetaut-Tong, H., Jaeger, J. J., Jongkanjanasoontorn, Y., and Suteethorn, V.. 1992. First fossil flying lemur; a dermopteran from the late Eocene of Thailand. Palaeontology, 35:373–380.Google Scholar
Efron, B., Halloran, E., and Holmes, S.. 1996. Bootstrap confidence levels for phylogenetic trees. Proceedings of the National Academy of Science U.S.A., 93:13,429–13,434.CrossRefGoogle ScholarPubMed
Felsenstein, J. 1985. Confidence limits on phylogenies: An approach using the bootstrap. Evolution, 39:783–791.CrossRefGoogle ScholarPubMed
Fox, R. C. 1990. The succession of Paleocene mammals in western Canada, p. 51–70. In Bown, T. M. and Rose, K. D. (eds.), Dawn of the Age of Mammals in the Northern Part of the Rocky Mountain Interior. Geological Society of America Special Paper 243.Google Scholar
Fox, R. C. and Youzwyshyn, G. P.. 1994. New primitive carnivorans (Mammalia) from the Paleocene of western Canada, and their bearing on relationships of the order. Journal of Vertebrate Paleontology, 14:382–404.CrossRefGoogle Scholar
Gelfo, J. N., Goin, F. J., Woodburne, M. O., and de Muizon, C.. 2009. Biochronological relationships of the earliest South American Paleogene mammalian faunas. Palaeontology, 52:251–269.CrossRefGoogle Scholar
Gidley, J. M. 1917. Notice of a new Paleocene mammal, a possible relative of the titanotheres. Proceedings of the U. S. National Museum, 52:431–435.CrossRefGoogle Scholar
Gill, T. 1872. Arrangement of the families of mammals with analytical tables. Smithsonian Miscellaneous Collections, 11:1–98.Google Scholar
Gingerich, P. D. and Childress, C. G. Jr. 1983. Barylambda churchilli, a new species of Pantolambdidae (Mammalia, Pantodonta) from the late Paleocene of western North America. Contributions from the Museum of Paleontology, The University of Michigan, 26:141–155.Google Scholar
Gregory, W. K. 1910. The orders of mammals. Bulletin of the American Museum of Natural History, 27:1–254.Google Scholar
Gunnell, G. F. 1989. Evolutionary history of Microsyopoidea (Mammalia, ?Primates) and the relationship between Plesiadapiformes and Primates. The University of Michigan, Papers on Paleontology, 27:1–157.Google Scholar
Hillis, D. M. and Bull, J. J.. 1993. An empirical test of bootstrapping as a method for assessing confidence in phylogenetic analysis. Systematic Biology, 42:182–192.CrossRefGoogle Scholar
Holtzman, R. C. 1978. Late Paleocene mammals of the Tongue River Formation, western North Dakota. Report of Investigation, North Dakota Geological Survey, 65:1–88.Google Scholar
Hunter, J. P. and Janis, C. M.. 2006. Spiny Norman in the Garden of Eden? Dispersal and early biogeography of Placentalia. Journal of Mammalian Evolution, 13:89–123.CrossRefGoogle Scholar
Jepsen, G. L. 1930. Stratigraphy and paleontology of the Paleocene of northeastern Park County, Wyoming. Proceedings of the American Philosophical Society, 69:463–528.Google Scholar
Jerzykiewicz, T. 1997. Stratigraphic framework of the uppermost Cretaceous to Paleocene strata of the Alberta Basin. Geological Survey of Canada Bulletin, 510:1–20.Google Scholar
Kielan-Jaworowska, Z. 1975. Preliminary description of two new eutherian genera from the Late Cretaceous of Mongolia, p. 5–16. In Kielan-Jaworowska, Z. (ed.), Results of the Polish-Mongolian Palaeontological Expeditions, Part VI. Palaeontologica Polonica, 33.Google Scholar
Kielan-Jaworowska, Z., Cifelli, R. L., and Luo, Z.-X.. 2004. Mammals from the Age of Dinosaurs. Columbia University Press, New York, 630 p.CrossRefGoogle Scholar
Kluge, A. G. and Wolf, A. J.. 1993. Cladistics: what's in a word? Cladistics, 9:183–199.CrossRefGoogle ScholarPubMed
Krause, D. W. and Maas, M. C.. 1990. The biogeographic origins of late Paleocene-early Eocene mammalian immigrants to the Western Interior of North America, p. 71–105. 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.CrossRefGoogle Scholar
Lillegraven, J. A. 1969. Latest Cretaceous mammals of upper part of Edmonton Formation of Alberta, Canada, and review of marsupialplacental dichotomy in mammalian evolution. The University of Kansas Paleontological Contributions, 50 (Vertebrata 12):1–122.Google Scholar
Linnaeus, C. 1758. Systema naturae per regna tria naturae, secundum classes, ordines, genera, species cum characteribus, differentiis, synonymis, locis (editio decima, reformata). Laurenti Salvii, Stockholm.Google Scholar
Lofgren, D. L., Lillegraven, J. A., Clemens, W. A., Gingerich, P. D., and Williamson, T. E.. 2004. Paleocene biochronology: The Puercan through Clarkforkian Land Mammal Ages, p. 43–105. In Woodburne, M. O. (ed.), Late Cretaceous and Cenozoic mammals of North America: Geochronology and Biostratigraphy. Columbia University Press, New York.CrossRefGoogle Scholar
Lucas, S. G. 1982. The phylogeny and composition of the order Pantodonta (Mammalia, Eutheria). Proceedings of the Third North American Paleontological Convention, 2:337–342.Google Scholar
Lucas, S. G. 1986. Systematics, biostratigraphy and evolution of early Cenozoic Coryphodon (Mammalia, Pantodonta). Unpublished Ph. D. dissertation, Yale University, New Haven, 673 p.Google Scholar
Lucas, S. G. 1993. Pantodonts, tillodonts, uintatheres, and pyrotheres are not ungulates, p. 182–194. In Szalay, F. S., Novacek, M. J., and McKenna, M. C. (eds.), Mammal Phylogeny: Placentals. Springer-Verlag, New York.CrossRefGoogle Scholar
Lucas, S. G. 1998. Pantodonta, p. 274–283. In Janis, C. M., Scott, K. M., and Jacobs, L. L. (eds.), Evolution of Tertiary Mammals of North America, volume 1: Terrestrial Carnivores, Ungulates, and Ungulatelike Mammals. Cambridge University Press, Cambridge.Google Scholar
MacPhee, R. D. E., Cartmill, M., and Rose, K. D.. 1989. Craniodental morphology and relationships of the supposed Eocene dermopteran Plagiomene (Mammalia). Journal of Vertebrate Paleontology, 9:329–349.CrossRefGoogle Scholar
Marsh, O. C. 1889. Discovery of Cretaceous Mammalia. American Journal of Science, series 3, 38:81–92.CrossRefGoogle Scholar
Marivaux, L., Bocat, L., Chaimanee, Y., Jaeger, J.-J., Marandat, B., Srisuk, P., Tafforeau, P., Yamee, C., and Welcomme, J.-L.. 2006. Cynocephalid dermopterans from the Paleogene of South Asia (Thailand, Myanmar and Pakistan): systematic, evolutionary and palaeobiogeographic implications. Zoologica Scripta, 35:395–420.CrossRefGoogle Scholar
Marshall, L. G., Sempere, T., and Butler, R. F.. 1997. Chronostratigraphy of the mammal-bearing Paleocene of South America. Journal of the South American Earth Sciences, 10:49–70.CrossRefGoogle Scholar
Matthew, W. D. 1918. A revision of the Lower Eocene Wasatch and Wind River faunas. Part V: Insectivora (continued), Glires, Edentata. Bulletin of the American Museum of Natural History, 38:565–657.Google Scholar
Matthew, W. D. 1937. Paleocene faunas of the San Juan Basin, New Mexico. Transactions of the American Philosophical Society, New Series, 30:1–510.CrossRefGoogle Scholar
McKenna, M. C. 1972. Vertebrate paleontology of the Togwotee Pass area, northwestern Wyoming, p. 80–101. In West, R. M. (ed.), Guidebook, Field Conference on Tertiary Biostratigraphy of Southern and Western Wyoming. Privately printed.Google Scholar
McKenna, M. C. 1975. Toward a phylogenetic classification of the Mammalia, p. 21–46. In Luckett, W. P. and Szalay, F. S. (eds.), Phylogeny of the Primates: A Multidisciplinary Approach. Plenum Press, New York.CrossRefGoogle Scholar
McKenna, M. C. 1990. Plagiomenids (Mammalia: ?Dermoptera) from the Oligocene of Oregon, Montana, and South Dakota, and middle Eocene of northwestern Wyoming, p. 211–234. In Bown, T. M. and Rose, K. D. (eds.), Dawn of the Age of Mammals in the Northern Part of the Rocky Mountain Interior. Geological Society of America Special Paper, 243.Google Scholar
McKenna, M. C. and Bell, S. K.. 1997. Classification of Mammals Above the Species Level. Columbia University Press, New York, xii+631 p.Google Scholar
Muizon, C. de and Cifelli, R. L.. 2000. The “condylarths” (archaic Ungulata, Mammalia) from the early Palaeocene of Tiupampa (Bolivia): implications on the origin of the South American ungulates. Geodiversitas, 22:47–150.Google Scholar
Muizon, C. de and Marshall, L. G.. 1992. Alcidedorbignya opinata (Mammalia: Pantodonta) from the early Paleocene of Bolivia: phylogenetic and paleobiogeographic implications. Journal of Paleontology, 66:499–520.CrossRefGoogle Scholar
Nessov, L.A.Nesov, L.A. 1985. New mammals from the Cretaceous of Kyzylkum [in Russian]. Vestnik Leningradskogo Universiteta, Seriâ 7, 17:8–18.Google Scholar
Nessov, L.A.Nesov, L.A., and Trofimov, B. A.. 1979. The oldest insectivore of the Cretaceous of the Uzbek SSR [in Russian]. Doklady Akademii Nauk SSSR, 247:952–954.Google Scholar
Osborn, H. F. 1898. Evolution of the Amblypoda. Part I. Taligrada and Pantodonta. Bulletin of the American Museum of Natural History, 10:269–218.Google Scholar
Parker, T. J. and Haswell, W. A.. 1897. A Text-book of Zoology. Vol. 2. Macmillan Press, London, 301 pp.Google Scholar
Patterson, B. 1933. A new species of the amblypod Titanoides from western Colorado. American Journal of Science, 25:415–425.CrossRefGoogle Scholar
Patterson, B. 1939. New Pantodonta and Dinocerata from the upper Paleocene of western Colorado. Geological Series of Field Museum of Natural History, 6:351–384.Google Scholar
Rose, K. D. 1973. The mandibular dentition of Plagiomene (Dermoptera, Plagiomenidae). Breviora, 411:1–17.Google Scholar
Rose, K. D. 1975. Elpidophorus, the earliest dermopteran (Dermoptera, Plagiomenidae). Journal of Mammalogy, 56:676–679.CrossRefGoogle Scholar
Rose, K. D. 1981. The Clarkforkian Land-Mammal Age and mammalian faunal composition across the Paleocene-Eocene boundary. University of Michigan Papers in Paleontology, 26:1–197.Google Scholar
Rose, K. D. 2006. The Beginning of the Age of Mammals. The Johns Hopkins University Press, Baltimore, 448 p.CrossRefGoogle Scholar
Rose, K. D. 2008. Plagiomenidae and Mixodectidae, p. 198–206. In Janis, C. M., Gunnell, G. F., and Uhen, M. D. (eds.), Evolution of Tertiary Mammals of North America Volume 2: Small Mammals, Xenarthrans, and Marine Mammals. Cambridge University Press, Cambridge.CrossRefGoogle Scholar
Rose, K. D. and Simons, E. L.. 1977. Dental function in the Plagiomenidae: Origin and relationships of the mammalian order Dermoptera. Contributions from the Museum of Paleontology, The University of Michigan, 24:221–236.Google Scholar
Rose, K. D. and Krause, D. W.. 1982. Cyriacotheriidae, a new family of early Tertiary pantodonts from western North America. Proceedings of the American Philosophical Society, 126:26–50.Google Scholar
Russell, L. S. 1948. A middle Paleocene mammal tooth from the Foothills of Alberta. American Journal of Science, 246:152–156.CrossRefGoogle Scholar
Sanderson, M. J. 1989. Confidence limits on phylogenies: The bootstrap revisited. Cladistics, 5:113–129.CrossRefGoogle ScholarPubMed
Scott, C. S. 1997. A new Palaeocene mammal site from Calgary, Alberta. Journal of Vertebrate Paleontology 17 supplement to no. 3:74A.Google Scholar
Scott, C. S. 2003. Late Torrejonian (middle Paleocene) mammals from south central Alberta, Canada. Journal of Paleontology, 77:745–768.2.0.CO;2>CrossRefGoogle Scholar
Scott, C. S. 2004. A new species of the ptilodontid multituberculate Prochetodon (Mammalia, Allotheria) from the Paleocene Paskapoo Formation of Alberta, Canada. Canadian Journal of Earth Sciences, 41:237–246.CrossRefGoogle Scholar
Scott, C. S. 2005. New species of Cyriacotherium (Mammalia: Pantodonta) from the Paleocene of Alberta, Canada. Journal of Vertebrate Paleontology 25 supplement to no. 3:112A.Google Scholar
Scott, C. S. 2008. Late Paleocene mammals from near Red Deer, Alberta, and a phylogenetic analysis of the earliest Lipotyphla (Mammalia, Insectivora). Unpublished Ph.D. dissertation, University of Alberta, Edmonton, Alberta, Canada, 1340 p.Google Scholar
Scott, C. S., Webb, M. W., and Fox, R. C.. 2006. Horolodectes sunae, an enigmatic mammal from the late Paleocene of Alberta, Canada. Journal of Paleontology, 80:1009–1025.CrossRefGoogle Scholar
Secord, R. 2008. The Tiffanian Land-Mammal Age (middle and late Paleocene) in the northern Bighorn Basin, Wyoming. University of Michigan Papers on Paleontology, 35:1–192.Google Scholar
Sempere, T., Butler, R. F., Richards, D. R., Marshall, L. G., Sharp, W., and Swisher, C. C. III. 1997. Stratigraphy and chronology of Upper Cretaceous-lower Paleogene strata in Bolivia and northwest Argentina. Geological Society of America Bulletin, 109:709–727.2.3.CO;2>CrossRefGoogle Scholar
Silcox, M. T., Bloch, J. I., Sargis, E. J., and Boyer, D. M.. 2005. Euarchonta, p. 127–144. In Rose, K. D. and Archibald, J. D. (eds.), The Rise of Placental Mammals. The Johns Hopkins University Press, Baltimore.Google Scholar
Simons, E. L. 1960. The Paleocene Pantodonta. Transactions of the American Philosophical Society, new series, 50:1–99.CrossRefGoogle Scholar
Simpson, G. G. 1927. Mammalian fauna and correlation of the Paskapoo Formation of Alberta. American Museum Novitates, 268:1–10.Google Scholar
Simpson, G. G. 1935. New Paleocene mammals from the Fort Union of Montana. Proceedings of the United States National Museum, 83:221–244.CrossRefGoogle Scholar
Simpson, G. G. 1937. Additions to the upper Paleocene fauna of the Crazy Mountain field. American Museum Novitates, 940:1–15.Google Scholar
Simpson, G. G. 1945. The principles of classification and a classification of mammals. Bulletin of the American Museum of Natural History, 85:1–350.Google Scholar
Soltis, P. S. and Soltis, D. E.. 2003. Applying the bootstrap in phylogeny reconstruction. Statistical Science, 18:256–267.CrossRefGoogle Scholar
Stafford, B. J. and Szalay, F. S.. 2000. Cranio-dental functional morphology and the taxonomy of flying lemurs (Dermoptera, Cynocephalidae). Journal of Mammalogy, 81:360–385.2.0.CO;2>CrossRefGoogle Scholar
Swofford, D. L. 2003. PAUP*4.0 β10. Phylogenetic Analysis Using Parsimony (*and Other Methods). Version 4. Sinauer Associates, Sunderland, Massachusetts.Google Scholar
Szalay, F. S. 1969. Mixodectidae, Microsyopidae, and the insectivore-primate transition. Bulletin of the American Museum of Natural History, 140:193–330.Google Scholar
Szalay, F. S. 1977. Phylogenetic relationships and a classification of the eutherian Mammalia, p. 315–374. In Hecht, M. K., Goody, P. C., and Hecht, B. M. (eds.), Major Patterns in Vertebrate Evolution. Plenum Press, New York.CrossRefGoogle Scholar
Thomas, O. 1908. The nomenclature of the flying-lemurs. The Annals and Magazine of Natural History, Series 8, 1:252–255.CrossRefGoogle Scholar
Ting, S. 1998. Paleocene and Early Eocene Land Mammal Ages of Asia, p. 124–147. In Beard, K. C. and Dawson, M. R. (eds.), Dawn of the Age of Mammals in Asia. Bulletin of Carnegie Museum of Natural History 34.Google Scholar
Van Valen, L. 1966. Deltatheridia, a new order of mammals. Bulletin of the American Museum of Natural History, 132:1–126.Google Scholar
Van Valen, L. 1967. New Paleocene insectivores and insectivore classification. Bulletin of the American Museum of Natural History, 132:1–126.Google Scholar
Van Valen, L. 1988. Paleocene dinosaurs or Cretaceous ungulates in South America? Evolutionary Monographs, 10:1–79.Google Scholar
Wang, B. 1975. Paleocene mammals of Chaling Basin, Hunan. Vertebrata PalAsiatica, 13:154–162. [in Chinese]Google Scholar
Wang, Y., Hu, Y., Chow, M., and Li, C.. 1998. Chinese Paleocene mammal faunas and their correlation, pp. 89–123. In Beard, K. C. and Dawson, M. R. (eds.), Dawn of the Age of Mammals in Asia, Bulletin of Carnegie Museum of Natural History 34.Google Scholar
Webb, M. W. 1996. Late Paleocene mammals from near Drayton Valley, Alberta. Unpublished , , Edmonton, 258 p.Google Scholar
Williamson, T. E. 1996. The beginning of the age of mammals in the San Juan Basin, New Mexico: biostratigraphy and evolution of Paleocene mammals of the Nacimiento Formation. Bulletin of the New Mexico Museum of Natural History, 8:1–141.Google Scholar
Williamson, T. E. and Lucas, S. G.. 1993. Paleocene vertebrate paleontology of the San Juan Basin, New Mexico. Bulletin of the New Mexico Museum of Natural History and Science, 2:105–135.Google Scholar
Xue, X., Yue, L., and Zhang, Y.. 1994. Magnetostratigraphical, biostratigraphical and lithostratigraphical correlation of the red beds in Shanyang Basin, Shaanxi Province. Science in China (Series B), 24:413–417. [in Chinese]Google Scholar
Xue, X., Zhang, Y., Bi, Y., Yue, L., and Chen, D.. 1996. The development and environmental changes of the intermontane basins in the eastern part of Qinling Mountains. Geological Publishing House, Beijing, People's Republic of China.Google Scholar