Browsing by Author "Emry, Robert J."
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ItemMorphology and relationships of Apternodus and other extinct, zalambdodont, placental mammals. Bulletin of the AMNH ; no. 273(New York, NY : American Museum of Natural History, 2002) Asher, Robert J.; McKenna, Malcolm C.; Emry, Robert J.; Tabrum, Alan R.; Kron, Donald G.We describe and illustrate new, middle Cenozoic fossils of dentally zalambdodont, North American placentals, including six relatively complete crania of Apternodus and two of Oligoryctes, as well as many partial skulls, mandibles, and teeth of these and other taxa. Several of the new Apternodus specimens are also associated with postcrania. We recognize seven species of Apternodus, three of which are new, formally propose the combination Oligoryctes altitalonidus, and recognize two other genera of small, North American, anatomically zalambdodont placentals, Parapternodus and Koniaryctes. We regard two other taxa previously associated with North American fossil zalambdodonts, one Bridgerian and the other Tiffanian, as valid but do not name them in this paper. In addition, we argue that dental zalambdodonty entails a primary occlusal relationship between the paracone and the ectoflexid, and the reduction or absence of the metacone and talonid basin. A phylogenetic analysis of cranial, dental, and postcranial characters of 30 fossil and Recent taxa leads us to conclude that (1) the Apternodontidae as defined in previous literature is not monophyletic and should be restricted to seven species of Apternodus, (2) the genus Oligoryctes contains at least two species and has a considerably longer geologic record than Apternodus, (3) neither Micropternodus nor currently known Paleocene taxa are closely related to Apternodus or Oligoryctes, and (4) a case can be made for a close relationship among modern soricids, Parapternodus, Koniaryctes, Oligoryctes and Apternodus to the exclusion of other insectivoran-grade taxa. With the use of ordered, multistate character transformations, Solenodon comprises the sister taxon to a soricid-fossil zalambdodont clade. ItemA new brontothere (Brontotheriidae, Perissodactyla, Mammalia) from the Eocene of the Ily Basin of Kazakstan and a phylogeny of Asian "horned" brontotheres. American Museum novitates ; no. 3439(New York, NY : American Museum of Natural History, 2004) Mihlbachler, Matthew Christian, 1972-; Lucas, Spencer G.; Emry, Robert J.; Bayshashov, Bolat.A new genus and species of 'horned' brontothere, Aktautitan hippopotamopus, from the Ily Basin of Kazakstan is described from three skulls and nearly complete postcranial material. This material occurs in fluvio-lacustrine red beds of the upper part of the Eocene (Irdinmanhan) Kyzylbulak Formation at Aktau Mountain. Trackways occurring in the overlying layers are also attributed to this new brontothere. Additionally, several misleading problems in the taxonomy of Asian horned brontotheres are addressed. We conclude that Protitan khaitshinus Yanovskaya, 1980 is a junior objective synonym of Metatitan relictus Granger and Gregory, 1943. Protitan reshetovi Yanovskaya, 1980 is removed from the genus Protitan and possibly belongs within Metatitan. Brachydiastematherium transylvanicum Böckh and Maty, 1876, the only bona fide European brontothere, known from a single partial mandible, is morphologically consistent with Metatitan Granger and Gregory, 1943. Although B. transylvanicum is known from very fragmentary material, it is possible that Metatitan is a junior synonym of Brachydiastematherium. The first cladistic phylogeny of middle and late Eocene Asian horned brontotheres was constructed with 40 characters and 17 taxa. Aktautitan, Metatitan, Brachydiastematherium, and Embolotherium form a monophyletic clade, with Aktautitan hippopotamopus as the most basal member of this clade. Within this clade, there are two monophyletic trichotomies: a Metatitan relictus, M. primus, Brachydiastematherium transylvanicum clade and a 'Metatitan' progressus, Embolotherium andrewsi, E. grangeri clade. The cladogram topology suggests that the elevated frontonasal horns shared by Aktautitan and Metatitan represent the ancestral morphology of the bizarre 'battering-ram' of Embolotherium. We extend the subfamily name Embolotheriinae to include these taxa. The unusually shortened distal limb segments of A. hippopotamopus resemble those of a phylogenetically disparate group of large ungulates that have convergently evolved hippolike limb proportions. We conclude that these limb proportions probably do not indicate a semiaquatic lifestyle, as had been previously surmised. ItemNew material of the Oligocene muroid rodent Nonomys, and its bearing on muroid origins. American Museum novitates ; no. 2712(New York, N.Y. : American Museum of Natural History, 1981) Emry, Robert J."New material shows that Nonomys simplicidens has the dental formula, and some of the dental characters, of the Cricetidae. These are combined with an hystricomorphous zygomasseteric structure like that in Dipodoidea, i.e., the enlarged foramen for the medial masseter is separated by a lamina of bone from a smaller foramen which transmits the infraorbital nerve and blood vessels, and there is virtually no development of a zygomatic plate. This ambiguous combination of characters is seen also in late Eocene Simimys, which has been classified as a dipodoid and as a muroid. Nonomys and Simimys are interpreted as members of an early radiation of myodont rodents, with derived characters that place them in the Muroidea rather than Dipodoidea, but with a combination of characters that excludes them from any presently defined family"--P. . ItemA new species of Agnotocastor (Rodentia, Castoridae) from the early Oligocene of Wyoming. American Museum novitates ; no. 2485(New York, N.Y. : American Museum of Natural History, 1972) Emry, Robert J."Two specimens from early Oligocene deposits of the Flagstaff Rim area, Natrona County, Wyoming, represent a new species of beaver, Agnotocastor galushai. Although this is the oldest recorded form that can be definitely referred to the Castoridae, it is already similar to later species and sheds very little additional light on the ancestry of the family"--P. . ItemA North American Oligocene pangolin and other additions to the Pholidota. Bulletin of the AMNH ; v. 142, article 6(New York : [American Museum of Natural History], 1970) Emry, Robert J.; Skinner, Morris F.; American Museum of Natural History. Frick Laboratories. ItemTributes to Malcolm C. McKenna : his students, his legacy. Bulletin of the AMNH ; no. 285(New York, NY : American Museum of Natural History, 2004) Gould, Gina C.; Bell, Susan K.; Mellett, James Silvan, 1936-; Kellner, Alexander Wilhelm Armin.; Rich, Thomas H. V.; Rich, Pat Vickers.; Engelmann, George F.; Cifelli, Richard.; Flynn, John J. (John Joseph), 1955-; Wyss, André R.; Meng, Jin (Paleontologist); Van Valen, Leigh.; Carrasco, Marc A.; Emry, Robert J.; Hunt, Robert M., Jr., 1941-; Rothwell, Tom.; Geisler, Jonathan H.; Gabbert, Sherri L.; Coombs, Margery Chalifoux.; Evander, Robert Lane, 1948-; MacFadden, Bruce J.; Prothero, Donald R. ItemA unique cricetid (Rodentia, Mammalia) from the early Oligocene of Natrona County, Wyoming. American Museum novitates ; no. 2508(New York, N.Y. : American Museum of Natural History, 1972) Emry, Robert J.; Dawson, Mary R.; Skinner, Morris F.; Galusha, Ted."Two specimens, a partial right mandibular ramus with M[subscript 1]-M[subscript 3] and an isolated left M[subscript 2], represent a new genus and species of rodent, Nanomys simplicidens. The teeth of this rodent are so lacking in special characters that its phylogenetic position is difficult to interpret, but it seems best referred to the Cricetidae"--P. . ItemVertebrate fossils and their context : contributions in honor of Richard H. Tedford. Bulletin of the AMNH ; no. 279(New York, NY : American Museum of Natural History, 2003) Flynn, Lawrence J. (Lawrence John), 1932-; Tedford, Richard H.; Novacek, Michael J.; Woodburne, Michael O.; Hunt, Robert M., Jr., 1941-; Gould, Gina C.; Gaffney, Eugene S.; Qiu, Zhanxiang.; Demere, Thomas A.; Berta, Annalisa.; Adam, Peter J.; Wang, Banyue.; Baskin, Jon A.; Van Valkenburgh, Blaire.; Sacco, Tyson.; Wang, Xiaoming, 1957-; Stevens, Margaret Skeels.; Stevens, James Bowie.; Lindsay, Everett H.; Whistler, David P.; Lander, E. Bruce.; Morgan, Gary S.; Lucas, Spencer G.; Ferrusquia-Villafranca, Ismael.; Webb, S. David (Sawney David), 1936-; Beatty, Brian Lee.; Poinar, George.; MacFadden, Bruce J.; Repenning, Charles A.; Turnbull, William D.; Lundelius, Ernest L.; Archer, Michael, 1945-; Pledge, Neville S.; Rich, Thomas H. V.; Darragh, Thomas A.; Rich, Pat Vickers.; Ye, Jie.; Meng, Jin (Paleontologist); Wu, Wenyu.; Qiu, Zhuding.; Li, Chuan-Kuei.; Winkler, Alisa J.; Downs, Will.; Holec, Peter.; Emry, Robert J.; McKenna, Malcolm C.; Lofgren, Donald L.; Tong, Haiyan.