University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Bulletin of the University of Nebraska State Museum Museum, University of Nebraska State 1975 Middle and Late Cenozoic Tapirs from Nebraska C. Bertrand Schultz Larry D. Martin R. George Corner Follow this and additional works at: https://digitalcommons.unl.edu/museumbulletin Part of the Entomology Commons, Geology Commons, Geomorphology Commons, Other Ecology and Evolutionary Biology Commons, Paleobiology Commons, Paleontology Commons, and the Sedimentology Commons This Article is brought to you for free and open access by the Museum, University of Nebraska State at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Bulletin of the University of Nebraska State Museum by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. BULLETIN OF VOLUME 10, NUMBER 1, PART 1 The University of Nebraska State Museum FEBRUARY, 1975 C. Bertrand Schultz Larry D. Martin R. George Corner Middle and Late Cenozoic Tapirs from Nebraska Frontispiece-Two views of U.N. S.M. Coil. Loc. Ft-40, the locality of the holotypes of ?Tapirus simpsoni, Aphe/ops kimba/lensis, Amebe/odon fricki, Barbourofelis fricki, and new forms of Te/eoceras, Prosthennops, and /ndarctos described in Parts 2, 3, and 4 of the present Bulletin. The upper photograph shows the face of the quarry as it was developed at the time of the discovery of the holotype of ?T. simpsoni in 1947. The "cap rock," which is typical of the upper part of the Kimball Formation in western Nebraska, was being blasted away (when the photograph was taken) in order to expose the fossil-bearing sediments below. The lower photograph shows the cross-bedded channel sands and silts, where so many of the Kimballian fossils are found at Coli. Loc. Ft-40. Some of the "cap rock" is exposed above the channel deposits. Photographs by Schultz. C. Bertrand Schultz Larry D. Martin R. George Corner CENOZOIC MAMMALS FROM THE CENTRAL GREAT PLAINS Part 1 Middle and Late Cenozoic Tapirs from Nebraska BULLETIN OF The University of Nebraska State Museum VOLUME 10, NUMBER 1, PART 1 FEBRUARY, 1975 BULLETIN OF VOLUME 10, NUMBER 1, PART 1 THE UNIVERSITY OF NEBRASKA STATE MUSEUM February, 1975 Pp. 1-21, Tables 1-3 Frontispiece, Figs. 1-13 ABSTRACT Part 1. Middle and Late Cenozoic Tapirs from Nebraska C. Bertrand Schultz Larry D. Martin R. George Corner The distribution and evolution of Late Cenozoic tapirs are discussed and the forms present in Nebraska are reported. Two new species are described from the Ogallala Pliocene of Nebraska, ?Tapirus johnsoni and ?T. simpsoni. Tapirs are known in Nebraska from the Early Oligocene through the Middle Pleistocene. The northern limit of the distribution of the tapirs contracts gradually southward in North America throughout the Tertiary, and even during the Pleistocene interglacials Nebraska must have been near the northern limit of their range. CONTRIBUTION OF The Department of Geology, College of Arts and Sciences, and the Division of Vertebrate Paleontology of the Museum. Copyright © 1975 by the Board of Regents of the University of Nebraska Library of Congress Catalog Card Number ISSN 0093-6812 Manufactured in the United States of America Schultz1 Martin2 Corner3 Middle and Late Cenozoic Tapirs from Nebraska INTRODUCTION contrast with that from South Dakota. This is in part a reflection of the more extensive and more Nebraska has the most complete sequence of productive Early Oligocene (Chadronian) beds late Cenozoic Continental sediments in North present in the latter state. The later Oligocene America, but almost no records of tapirs have beds (Brule Formation) seem to have been de­ been reported from these sediments. Radinsky posited in a less humid environment and tapirs (1963, p. 65) mentions a Nebraska speci men are less abundant in these sediments. Two gen­ housed in the Frick Laboratory of the American era of Oligocene tapirs, C%don and Protapirus, Museum of Natural History, which he identified are known to occur in North America. Only as C%don occidenta/is. He did not give further C%don is known from Nebraska. C%don locality information, identify the elements pres­ belongs to the extinct family Helaletidae which ent, give the stratigraphic horizon, or include the may have given rise to the Tapiridae (Radinsky, occurrence on his map showing the distribution 1963, pp. 94-96.) of Late Eocene and Oligocene tapirs (Radinsky, The earliest tapirid is Protapirus, which may 1963, Fig. 17). Nor was this occurrence plotted have been ancestral to Miotapirus, a genus on Bjork's (1968, Fig. 2) map giving the distribu­ known from the early Miocene of Wyoming, tion of C%don in North America. No additional South Dakota, and Nebraska (Schlaikjer, 1937; published Nebraska records have come to our Macdonald, 1970; Marti n, 1973). Protapirus attention. The scarcity of tapirs in Late Cenozoic robustus has been described from sediments deposits seems to be general in North America, considered to be early Miocene from the John and may be due to lack of extensive subtropical Day Region of Oregon (Sinclair, 1901). The skull forests during this time. of Miotapirus is much more modern than that of The present paper records the distribution of Protapirus. The nasals of Miotapirus are more tapirs in Nebraska from Oligocene to Pleis­ retracted, the diastema is longer, and the palate tocene. The Oligocene record is quite poor in does not extend as far posteriorly. The skull of Miotapirus resembles that of the later genus Tapiravus in having a relatively deep maxilla with a very shallow sulcus on the ascending part of lCurator of Vertebrate Paleontology, University of Nebraska State Museum; and Professor of Geology, Department of the maxillary. No certain records of Hemingfor­ Geology. dian tapirs have been reported, although 2Assistant Curator of Vertebrate Paleontology, University Tapiravus va/idus Marsh may be late Miocene. of Kansas Museum of Natural History; Assistant Professor of Systematics and Ecology, University of Kansas; and Re­ Tapiravus va/idus is known from the type speci­ search Affiliate, Division of Vertebrate Paleontology, Univer­ men from New Jersey and from the Calvert For­ sity of Nebraska State Museum. mation along Chesapeake Bay in Maryland 3Highway Salvage Paleontologist, State of Nebraska De­ partment of Roads; and Division of Vertebrate Paleontology, (Gazin and Collins, 1950, pp. 11-13). The University of Nebraska State Museum. holotype of T. rarus Marsh has never been illus- 2 I BULLETIN OF THE UNIVERSITY OF NEBRASKA STATE MUSEUM trated. It is from "the Lower Pliocene east of the Referred Specimens.-Partial Palate with Rocky Mountains" (Marsh, 1877, p. 252). Thus ILP3 and partial mandible with P:z-M2, U.N.S.M. the precise geological and geographical prove­ 45113 (Fig. 1B, Tables 1 and 2). nience of the holotype is virtually unknown. Locality of Referred Specimens.-U.N.S.M.5 Tapiravus has also been reported from the Late Coli. Loc. Sx-120, secs. 27-28, T. 34N., R. 57W., Miocene or Early Pliocene of the Bone Valley Sioux County, Nebraska. gravels in Florida, and is recorded in this paper from Nebraska. Tapiravus seems to be restricted Stratigraphic Occurrence.-From a channel to the Late Miocene or Early Pliocene (Valenti­ fill probably equivalent to the Toadstool Channel nian Provincial Age).4 We have referred all the in the Orella Member of the Brule Formation, Clarendon ian and later North American Tertiary White River Group, Oligocene (See Schultz and tapirs discussed in this paper to ?Tapirus. Stout, 1955). Pleistocene records of Tapirus are rare in Ne­ Description.-Upper diastema short; rostrum braska (Fig. 12), suggesting that even during in­ broad; incisive foramina broad but compara­ terglacials this area was near the northern limit tively short; palate narrow anteriorly; incisors of its range (Fig. 13). large, spatulate, and decreasing in size pos­ teriorly; pl small, triangular, with a small antero­ SYSTEMATIC DESCRIPTIONS lingualloph; p2·3 molariform with protocone and hypocone separated, protoloph and metaloph Class: MAMMALIA subparallel, small but distinct parastyle, Order: PERISSODACTYLA metacone elongated posteriorly, trace of a labial cingulum present posteriorly; posterior cing­ Superfamily: TAPIROIDEA ulum well-developed on p2; anterior and pos­ Family HELALETIDAE terior cingula well developed on p3; mandible Genus: C%don Marsh, 1890 relatively short, deep and robust with broad symphysis, roughened and slightly excavated Colodon occidentalis (Leidy), 1868 behind Ia (pathologic?), three small mental foramina present; three incisors present; canine Holotype.-M3, presumably at Academy of abserit; base of crown of p2 indicating small Natural Sciences of Philadelphia (see Radinsky, triangular tooth; p3 subtriangular with promi­ 1968, p. 63, for a detailed account of the occur­ nent paralophid across anterior end and con­ rence of the type of C. occidenta/is). necting with protoconid, metaconid largest Type Locality.-Bad Lands of either South cusp; entoconid large and isolated from Dakota or Nebraska. hypolophid on P3-4 nearly square with re­ duced paralophid and large protoconid; anterior Stratigraphic Occurrence.-? Chadronian. and posterior cingula present on P3-M3 but nearly removed by interstitial wear; lingual and 4Because of the lack of consistency in the use of the term labial cingula only faintly developed on M2-3; mo­ "Pliocene" by various workers, the present writers are con­ lars elongate and increasing in size posteriorly;