Browsing by Author "Cifelli, Richard."
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Item Biostratigraphy of the Casamayoran, Early Eocene of Patagonia. American Museum novitates ; no. 2820(New York, N.Y. : American Museum of Natural History, 1985) Cifelli, Richard.; Simpson, George Gaylord, 1902-; Scarritt Patagonian Expedition 1930-1931)"The Casamayoran, presumed to pertain to the early Eocene, is the most diverse and best known of South America's early to middle Tertiary land mammal ages. Because the composition of local faunas and the stratigraphic position of assemblages at any given locality have not been evaluated, however, the Casamyoran has remained a dimensionless age, despite its seminal importance to understanding the early radiations of mammals on the South American continent. Preliminary analysis of field data and collections obtained by G.G. Simpson in 1930-1931 suggests a faunal succession in the Casamayoran of Patagonia. Large, well documented samples are available from two localities with relatively wide stratigraphic distributions of Casamayoran mammals: Cañadón Vaca and the Gran Barranca south of Lago Colhué Huapí, central Chubut. The compositions of these two local faunas differ markedly, and lithostratigraphic, biostratigraphic, and paleontologic evidence suggests that these differences are temporal and not ecological in nature. Faunal composition of the two localities is compared qualitatively and statistically with respect to the magnitude of difference seen in preceding and succeeding South American land mammal ages and to roughly equivalent North American land mammal ages. Two new subdivisions of the Casamayoran, the Barrancan and the Vacan, are defined on this basis. In addition, a composite stratigraphic plot of taxa from the younger of the two localities (the Gran Barranca) produced a number of non-overlapping range zones within the Barrancan; statistical analysis indicates that the probability these observations are due to sampling error is small in most, but not all, cases. The other Patagonian local faunas are briefly considered with respect to this scheme, and an hypothesis of their relative ages is presented"--P. [1].Item Eutherian tarsals from the late Paleocene of Brazil. American Museum novitates ; no. 2761(New York, N.Y. : American Museum of Natural History, 1983) Cifelli, Richard."Disassociated eutherian proximal tarsals (astragalus, calcaneum) from Riochican (late Paleocene) fissure fills near São José de Itaboraí, Rio de Janeiro, Brazil, are described and, where feasible, are assigned to dental species from that locality, based on predicted morphology, relative size, and relative abundance. Two cingulate xenarthrans are present; one is probably a dasypodid, whereas the other may pertain to the Glyptodontidae. Ankle specializations of Carodnia vierai are unlike those of astrapotheres and Dinocerata, but similar to those of Pyrotherium and suggest reference to the Pyrotheria; Tetragonostylops apthomasi is pedally a primitive astrapothere. Notoungulate tarsals from Itaboraí, referred to Camargomendesia pristina (Henricosborniidae) and Colbertia magellanica (?Oldfieldthomasiidae), are of generalized aspect within the order, and represent a primitive morphotype from which later notoungulate families diverged. Litoptern tarsals are assigned to three species, Anisolambda prodromus, Ernestokokenia parayirunhor, and a new form; astragali and calcanea of 'condylarth' aspect are referred to Lamegoia conodonta, Victorlemoinea prototypica, and Ernestokokenia protocenica. The fact that some dentally primitive taxa (including a supposed congener of a dental and tarsal condylarth) bear the diagnostic litoptern ankle specializations, whereas others, including an advanced and dentally litoptern-like form do not, heightens the problem of distinguishing the two groups as currently recognized, and indicates that the fundamental specializations of the Litopterna are postcranial, not dental. Victorlemoinea, heretofore considered a macraucheniid litoptern but probably pertaining to the new family, Sparnotheriodontidae, shares derived pedal characters with the didolodonts; among the didolodonts, Ernestokokenia protocenica, Lamegoia conodonta, and ?Didolodus sp. seem to form a natural (monophyletic) group definable by tarsal features"--P. [1].Item The origin and affinities of the South American Condylarthra and early Tertiary Litopterna (Mammalia). American Museum novitates ; no. 2772(New York, N.Y. : American Museum of Natural History, 1983) Cifelli, Richard."A previously unknown genus and species of a primitive litoptern from the late Paleocene (Riochican) of Itaboraí, Brazil, is described, and three previously described didolodontid and litoptern species from Itaboraí are referred to new genera. Comparative analysis of the dentition of didolodontids and primitive Litopterna suggests a number of revisions in their taxonomy. The two Itaboraí didolodonts appear to be more closely related to each other than to Patagonian forms; Protolipterna, new genus, Miguelsoria, new genus, ?and Asmithwoodwardia are placed in the Litopterna in a new family, Protolipternidae. Anisolambda (including Ricardolydekkeria and Josepholeidya) and allies seem to be related to true proterotheriids, and are placed in the Proterotheriidae in a new subfamily, Anisolambdinae, whereas the Polymorphinae (including only the type genus) appears to be related to the Macraucheniidae. Proectocion (including Oxybunotherium), previously referred to the Didolodontidae, is placed in the advanced litoptern family Adianthidae. An ancestral morphotype for the Litopterna and Didolodontidae is constructed on the basis of their known morphology and by comparison with primitive oxyclaenine arctocyonids such as Protungulatum. Relevant North American ungulate families (Arctocyonidae, Hyopsodontidae, Phenacodontidae, Periptychidae) are briefly reviewed and their members compared with this hypothetical ancestor. The primitive litoptern/didolodont morphotype is closely comparable to and shares derived conditions with Torrejonian mioclaenine hyopsodonts such as Litaletes. Such an exclusive relationship implies that the indigenous South American ungulate orders may not represent a strictly monophyletic unit with respect to other Eutheria"--P. [1].Item Systematics of the Adianthidae (Litopterna, Mammalia). American Museum novitates ; no. 2771(New York, N.Y. : American Museum of Natural History, 1983) Cifelli, Richard.; Soria, Miguel F. (Miguel Fernando)"The genera and species of previously known Adianthidae are revised, with descriptions of original and more recently collected specimens. Proectocion, usually placed in the Didolodontidae, is in known morphology an appropriate primitive morphotype for the family. Adiantoides and the recently described Indalecia are placed in the subfamily Indaleciinae, which includes somewhat aberrant Eocene ?adianthids. Tricoelodus, usually considered of doubtful validity and affinities, is the best known genus and is represented by a new species from the Deseadan of Bolivia in addition to the type. Tricoelodus, Proadiantus, and Thadanius (a new monotypic genus from the Deseadan of Bolivia) form a monophyletic subgroup of Adianthidae, Thadanius being the most primitive; Adianthus may be most closely related to Proheptaconus"--P. [1].Item Tributes 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.