Browsing by Author "Rich, Pat Vickers."
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Item Brachyerix, a Miocene hedgehog from western North America, with a description of the tympanic regions of Paraechinus and Podogymnura. American Museum novitates ; no. 2477(New York, N.Y. : American Museum of Natural History, 1971) Rich, Thomas H. V.; Rich, Pat Vickers."Although living hedgehogs have long been regarded [as] the archetypes of the primitive placental mammal, they have nonetheless had a complex Cenozoic history that is reflected in the recognition of three extinct and two living erinaceid subfamilies. Members of one extinct subfamily, the Brachyericinae, underwent a remarkable shortening of the skull and a reduction in the number of teeth during the Oligocene, Miocene, and early Pliocene. This trend culminated in the two North American genera, Brachyerix and Metechinus, in which only three teeth were retained anterior to P[subscript]4. Dimylechinus, a European form from the early Miocene, and Exallerix from the medial Oligocene of Asia both retained at least four teeth anterior to P[subscript]4. None of the four genera had an M[subscript]3. Brachyerix and Metechinus occur from the Great Plains to the Pacific coast of North America. Brachyerix is temporally restricted to the Miocene; Metechinus occurs in late Miocene and early Pliocene sediments. Although both genera are known from several localities, they are never found together, which may reflect an ecological separation of these two forms during temporal overlap. Both are known only from cranial osteology. During the past 40 years, the differences between these two North American genera have not been well defined, and only now with the availability of several specimens of each can the generic boundaries be adequately reviewed. Two species of Brachyerix are recognized in the present paper. Brachyerix macrotis, restricted to the early and medial Miocene, is the larger of the two and differs from B. incertis, new combination (late Miocene), in having a stronger lingual cingulum on P[superscript]3 and in entirely lacking a P[superscript]3 protocone. Metechinus marslandensis can now be synonymized with B. macrotis, whereas Talpa incerta and Metechinus fergusoni are both junior synonyms of B. incertis. Only Metechinus nevadensis still requires generic separation owing to its unique basicranium, small auditory bullae, nature of the sagittal crest, and relatively anteroposteriorly compressed M[subscript]1 trigonid. Dimylechinus bernoullii is an adequate structural ancestor for Brachyerix macrotis and its descendents. However, as both Dimylechinus and Exallerix are known only from single specimens, their relationship to the North American brachyericines as well as to one another is not well understood and will not be until further specimens are found. An appendix describing the ear regions of two living hedgehog genera, Paraechinus and Podogymnura, is included to supplement Butler's (1948) paper on the erinaceid ear region. Paraechinus is the only living erinaceid that has bony tubes covering part of the blood vessels contained in the tympanic cavity, a condition developed to the extreme in the Miocene Brachyerix"--P. [1]-2.Item Chubutemys, a new eucryptodiran turtle from the early Cretaceous of Argentina, and the relationships of the Meiolaniidae ; American Museum novitates, no. 3599(New York, NY : American Museum of Natural History, 2007) Gaffney, Eugene S.; Rich, Thomas H. V.; Rich, Pat Vickers.; Constantine, Andrew Eric, 1965-; Vacca, Raul.; Kool, Lesley.Chubutemys copelloi is the oldest nonmarine cryptodire from South America represented by a skull. The skull and associated postcranial fragments are from the Aptian Cerro CostaŠno Member of the Cerro Barcino Formation of Chubut, Argentina. Chubutemys has a processus trochlearis oticum, showing that it is a cryptodire, and an enclosed canalis caroticus internus extending to the posterior margin of the pterygoid, showing that it is a eucryptodire. The skull of Chubutemys is similar to that of other primitive eucryptodires, particularly Dracochelys, but also to Hangaiemys, Judithemys, Sinemys, and Ordosemys. Chubutemys differs from all these, however, in possessing a solidly roofed skull, formed by long, wide parietals, rather than a posterior emargination. Chubutemys also differs from these taxa in having no cheek emargination. A phylogenetic analysis using PAUP* analyzed 104 parsimony-informative characters resolving into one most parsimonious cladogram of 224 steps, a consistency index of 0.55, and a retention index of 0.74. The phylogenetic analysis weakly joins Chubutemys and meiolaniids on the basis of the prefrontal-postorbital contact. Chubutemys also has a fully roofed skull and slitlike posterior opening of the foramen caroticum laterale (foramen posterius canalis caroticus laterale), features to be expected in a meiolaniid sister taxon. Chubutemys provides further evidence that meiolaniids are related to 'basal' eucryptodires ('sinemydids/macrobaenids'), that is, eucryptodires outside the living Cryptodira, the Polycryptodira. The basicranial morphology of meiolaniids, with an intrapterygoid slit, rather than being a unique feature of the group is instead a modified state of the primitive eucryptodire condition, as seen in such forms as Chubutemys, Dracochelys, Ordosemys, and Sinemys. The intrapterygoid slit of meiolaniids is homologous with the pterygoid flange associated with the foramen caroticum laterale (foramen posterius canalis caroticus laterale of Sukhanov) in non-Polycryptodiran eucryptodires like Ordosemys. Chubutemys shows that nonmarine eucryptodires were present in South America in the Cretaceous, as they were in North America, central Asia, and Australia.Item Early Pleistocene pre-glacial and glacial rocks and faunas of north-central Nebraska. Bulletin of the AMNH ; v. 148, article 1(New York : [American Museum of Natural History], 1972) Skinner, Morris F.; Hibbard, Claude William, 1905-1973.; Gutentag, Edwin D., 1931-; Smith, G. R.; Lundberg, John G.; Holman, J. Alan.; Feduccia, Alan.; Rich, Pat Vickers."A study of the early Pleistocene rocks of the non-glaciated region of north-central Nebraska shows that a paleovalley fill (Keim Formation, new name) that contained the Sand Draw local fauna was preglacial. The stratigraphic position of the overlying Long Pine Formation, new name, is significant because it is the first evidence of a fluvioglacial outwash in the area. Two later sets of deposits overlie the Long Pine formation: Duffy and Pettijohn formations, new names. The source of the gravel in the Long Pine Formation has been a matter of conjecture, some geologists believing it to be the Black Hills, and others the Rocky Mountains. Supporting evidence for either provenience is lacking. Devonian fossils in the Long Pine Gravel indicate that the source was to the north-northeast near Lake Winnepegosis in Manitoba. The Sand Draw local fauna, previously considered Nebraskan (first continental glacier) or Aftonian (first interstadial), correlates with other Blancan faunas, and is the most diverse and northern known of Blancan time. The following groups comprise the fauna: 42 taxa of molluscs, 14 taxa of ostracodes, 10 taxa of fishes (Chaenobryttus serratus, new species), four taxa of amphibians, 14 taxa of reptiles (Geochelone oelrichi, new species), at least 10 taxa of birds, and 35 taxa of mammals. The mammalian fauna has these new forms: a shrew, Planisorex dixonensis, new genus; four rodents, Spermophilus boothi, new species; Spermophilus meltoni, new species; Ophiomys magilli, new species; Ophiomys fricki, new species; and a mustelid, Buisnictis burrowsi, new species. Some of these fossils indicate that the early Pleistocene climate was warmer than the present one, sub-humid, with evapo-transpiration about equal to average annual precipitation. Presence of the large land tortoise, Geochelone, is evidence that the temperature seldom, if ever, dropped below 0°C. Pollen from the Keim Formation is definaitely not of glacial type"--P. 11.Item Otwayemys, a new cryptodiran turtle from the early Cretaceous of Australia. American Museum novitates ; no. 3233(New York, NY : American Museum of Natural History, 1998) Gaffney, Eugene S.; Kool, Lesley.; Brinkman, Donald B.; Rich, Thomas H. V.; Rich, Pat Vickers."The Early Cretaceous Eumeralla Formation, Otway Group, of Cape Otway, Victoria, Australia, has yielded remains of a new genus of eucryptodiran turtle, Otwayemys cunicularius, n. gen., n. sp. Otwayemys is based primarily on shell material, but unassociated skull elements, cervical and caudal vertebrae, and limb elements from the type locality are attributed to this taxon. Otwayemys cunicularius is characterized by a carapace with an emarginate nuchal area, wide vertebral scales, and a smooth shell texture; and by a plastron with wide epiplastra, small extragular scales (scale set 2), gular scales (scale set 1) extending onto entoplastron, a small and narrow entoplastron, a large hyoplastron/hypoplastron fontanelle, and an inguinal buttress terminating on the sixth peripheral. The shell of Otwayemys is most similar to Xinjiangchelys from the Jurassic of China; both have broad epiplastra, plastral buttresses not extending onto costals, a long first thoracic rib, no inclination to the first thoracic centrum, and no mesoplastra; all these characters are primitive for the Eucryptodira. Otwayemys is advanced over Xinjiangchelys in having formed vertebral articulations in the neck. Biconvex eighth and biconcave fifth (?) cervicals in Otwayemys are characters found in the Early Cretaceous Ordosemys of central Asia. Otwayemys differs from Chelycarapookus, also from the Early Cretaceous of Victoria, in being 20% larger and having a large plastral fontanelle, a smooth surface texture, and a wide posterior plastral lobe. Otwayemys belongs in the Centrocryptodira, eucryptodires with formed vertebral articulations. A parsimony analysis of 18 taxa using 40 characters (of which only 20 are known for Otwayemys) produces 12 equally parsimonious trees. A consensus tree shows Otwayemys and Meiolaniidae in an unresolved trichotomy with Polycryptodira (consisting primarily of the living cryptodires) plus Sinemydidae"--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.Item Vertebrate 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.