Abstract
Five new species of marsupials are described from the middle Eocene La Meseta Formation of Seymour Island, Antarctic Peninsula. Three are derorhynchid didelphimorphians; one species is a prepidolopid polydolopimorphian, and the last is a microbiotheriid australidelphian. Additionally, fragmentary specimens representing an indetermined derorhynchid and a possible marsupial are also described. The prepidolopid and one of the derorhynchids are sufficiently derived as to preclude any close relationship to other members of that family, but the remaining taxa show the closest affinity with species otherwise known only from Itaboraian and older faunas in Patagonia. This differs from the affinity to early Eocene (Casamayoran) taxa shown by the polydolopid marsupials and placental mammals previously known from the La Meseta Formation. The newly described marsupials indicate that the relict La Meseta Fauna is composed of forms that must have dispersed to Antarctica no later than about early late Paleocene, whereas the previously known taxa apparently arrived in the early Eocene. Ecologically, the La Meseta Fauna is composed mostly of small-sized marsupials of likely insectivorous to frugivorous habits and larger-sized placental herbivores. Whereas the ratite bird of the La Meseta Fauna was probably also herbivorous, the phorusrhachoid and falconid birds comprised a large and smaller carnivorous to possibly scavenging component, respectively. Compared to contemporary faunas of Patagonia, the medium- to large-sized marsupial carnivores are lacking in the Antarctic Peninsula. Nevertheless, the La Meseta Fauna is Patagonian in origin and affinity. In conjunction with new faunas of Itaboraian age (early late Paleocene) in Patagonia, the evidence available indicates that from at least Itaboraian time onward the land mammal fauna of Patagonia and northern South America, as well, is a self-contained unit, developing the diversity characteristic of the Paleogene in that continent, including the australidelphian (but South American) microbiotheres. This, in combination with the apparent separation of Australia from Antarctica at ca. 64 Ma, reinforces interpretations that the precursors of the Australian marsupial fauna most likely dispersed from South America to Australia in the late Cretaceous–early Paleocene.
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LITERATURE CITED
Askin, R. A. (1995). Eocene terrestrial palinology of Seymour Island, Antarctica. In: VII International Symposium on Antarctic Earth Science, p. 14, Sienna.
Bond, M., Pascual, R., Reguero, M. A., Santillana, S. H., and Marenssi, S. A. (1990). Los primeros ungulados extinguidos sudamericanos de la Antártida. Ameghiniana 26: 240.
Bond, M., Carlini, A. A., Goin, F. J., Legarreta, L., Ortiz-Jaureguizar, E., Pascual, R., and Uliana, M. A. (1995). Episodes in South American land mammal evolution and sedimentation: Testing their apparent concurrence in a Paleocene succession from central Patagonia. In: IV Congr. Arg. Paleontol. Bioestrat., pp. 47–58, Asoc. Paleont. Argentina, Trelew.
Bown, T. M., and Kraus, M. J. (1979). Origin of the tribosphenic molar and metatherian and cutherian dental formulae. In: Mesozoic Mammals. The First Two-Thirds of Mammalian History, J. A. Lillegraven, Z. Kielan-Jaworowska, and W. A. Clemens, eds., pp. 172–181, University of California Press, Berkeley.
Brea, M., and Zucol, A. F. (1996). Estructura reproductiva femenina de una conífera de la Formación La Meseta, Isla Seymour, Antártida. In: Congr. Paleógeno Am. Sur, p. 28, Santa Rosa.
Candela, A. M., and Goin, F. J. (1994). Revisión de las especies antárticas de marsupiales polidolopinos (Polydolopimorphia, Polydolopidae). In: III Jornadas de Comunicaciones Sobre Investigaciones Antárticas, pp. 55–56, Instituto Antártico Argentino, Buenos Aires.
Candela, A. M., Goin, F. J., and Pascual, R. (1998). Los Polydolopimorphia (Mammalia, Marsupialia) de la Formación Las Flores (Paleoceno medio, Patagonia central, Argentina). Acta Zool. Lilloana 18: 158.
Case, J. A., Woodburne, M. O., and Chaney, D. S. (1988). A new genus and species of polydolopid marsupial from the La Meseta Formation, late Eocene, Seymour Island, Antarctic Peninsula. In: Geology and Paleontology of Seymour Island, R. M. Feldmann and M. O. Woodburne, eds., pp. 505–521, Geol. Soc. Am. Mem. 169, Boulder, CO.
Case, J. A., Goin, F. J., and Woodburne, M. O. (1996). Eocene Antarctic ameridelphian marsupials with tribosphenic molars: Implications upon marsupial biogeography. J. Vert. Paleontol. 16: 26A.
Elliot, D. H., and Trautman, T. (1982). Lower Tertiary strata on Seymour Island. In: Antarctic Geoscience, C. Craddock, ed., pp. 46–55, Madison, New York.
Gandolfo, M. A. (1994). Evolución del género Nothofagus Blune basada en su morfología foliar comparada, Unpublished thesis, University of Buenos Aires, Buenos Aires.
Gandolfo, M. A., Santillana, S. N., and Marenssi, S. A. (1999). Flora y paleoclima de la Formación La Meseta (Eoceno-Oligoceno inferior?), Isla Marambio. In: Paleógeno de América del Sur y de la Península Antártica, Spec. Publ. 5, Asociación Paleontológica Argentina, Buenos Aires (in press).
Goin, F. J., and Candela, A. M. (1995). Una nueva especie de Epidolops Paula Couto, 1952 (Marsupialia, Polydolopimorphia, Polydolopidae). Consideraciones sobre el patrón molar inferior de los Epidolopidae. In: VI Congreso Argentino de Paleontología y Bioestratigrafía, pp. 143–148, Asoc. Paleont. Argentina, Trelew.
Goin, F. J., and Candela, A. M. (1996). A new early Eocene polydolopimorphian (Mammalia, Marsupialia) from Patagonia. J. Vert. Paleontol. 16: 292–296.
Goin, F. J., and Carlini, A. A. (1995). An early Tertiary microbiotheriid marsupial from Antarctica. J. Vert. Paleontol. 15: 205–207.
Goin, F. J., and Reguero, M. A. (1993). Un enigmático insectívoro del Eoceno de Antártida. Ameghiniana 30: 108.
Goin, F. J., Reguero, M. A., and Vizcaíno, S. F. (1994). Novedosos hallazgos de “comadrejas” (Marsupialia) del Eoceno Medio de Antártida. In: III Jornadas de Comunicaciones Sobre Investigaciones Antárticas, pp. 59–61, Instituto Antártico Argentino, Buenos Aires.
Goin, F. J., Candela, A. M., and Forasiepi, A. (1997). New, middle Paleocene marsupials from Central Patagonia. 57 Annual Meeting of the Society of Vertebrate Paleontology, Chicago, Abstracts, 49A.
Goin, F. J., Candela, A. M., and López, G. (1998). New, Middle Eocene marsupials from Antofagasta de la Sierra, Northwestern Argentina. Geobios 31: 75–85.
Hershkovitz, P. (1982). The staggered marsupial lower third incisor (13). Géobios Mem. Spec. 6: 191–200.
Hershkovitz, P. (1995). The staggered marsupial lower third incisor: Hallmark of cohort Didelphimorphia, and description of a new genus and species with staggered 13 from the Albian (Lower Cretaceous) of Texas. Bonn. Zool. Beitr. 45: 153–169.
Lusky, J. C., Reguero, M. A., and Vizcaíno, S. F. (1994). Geographical position applying Global Position System (GPS) in the Eocene land-vertebrate bearing localities from Seymour (Marambio) Island, Antarctic Peninsula. In: III Jornadas de Comunicaciones Sobre Investigaciones Antárticas, pp. 53–54, Instituto Antártico Argentino, Buenos Aires.
Marenssi, S. A., and Santillana, S. N. (1994). Unconformity bounded units within La Meseta Formation, Seymour Island, Antarctica: A preliminary approach. In: XXI Polar Symposium, M. Zalewski (ed.), pp. 33–37, Warsaw.
Marenssi, S. A., Reguero, M. A., Santillana, S. N., and Vizcaíno, S. F. (1994). Eocene land mammals from Seymour Island, Antarctica: Paleobiological implications. Antarctic Sci. 6: 3–15.
Marshall, L. G. (1978). Evolution of the Borhyaenidae, extinct South American predaceous marsupials. Univ. Calif. Publ. Geol. Sci. 177: 1–89.
Marshall, L. G. (1982). Systematics of the extinct South American marsupial family Polydolopidae. Fieldiana Geol. (n.s) 12: 1–109.
Marshall, L. G. (1987). Systematics of Itaboraian (middle Paleocene) age “opossum-like” marsupials from the limestone quarry at Sao José de Itaborai, Brasil. In: Possums and Opossums: Studies in Evolution, M. Archer, ed., pp. 61–160, Surrey Beatty and Sons, Chipping Norton, NSW.
Marshall, L. G., and Muizon, C. de (1988). The dawn of the Age of Mammals in South America. Natl. Geogr. Res. 4(1): 23–55.
Marshall, L. G., Case, J. A., and Woodburne, M. O. (1990). Phylogenetic relationships of the families of marsupials. In: Current Mammalogy, Vol. 2, H. H. Genoways, ed., pp. 433–505, Plenum Press, New York.
Massoia, E., and Chebez, J. C. (1993). Mamíferos Silvestres del Archipiélago Fueguino, LOLA, Literature of Latin America, Buenos Aires.
Muizon, C. de (1991). La fauna de mamíferos de Tiupampa (Paleoceno inferior, Formación Santa Lucía), Bolivia. In: Fósiles y Fácies de Bolivia, Vol. I. Vertebrados, R. Suarez-Soruco, ed., pp. 575–624, Revista Técnica de YPFB 12, Santa Cruz de la Sierra.
Muizon, C. de, and Brito, I. M. (1993). Le bassin calcaire de São José de Itaboraí (Rio de Janeiro, Brésil): Ses relations fauniques avec le site de Tiupampa (Cochabamba, Bolivie). Ann. Paléontol. 79(3): 233–269.
Oliveira, E. V. (1998). Taxonomia, Filogenia e Paleobiogeografia de marsupiais “Poliprotodontes” do Mesopaleoceno da Bacia de Itaboraí, Rio de Janeiro, Brasil, Unpublished thesis, University of Rio Grande do Sul, Porto Alegre.
Paula Couto, C., de (1952). Fossil mammals from the beginning of the Cenozoic in Brazil. Marsupialia: Polydolopidae and Borhyacnidae. Am. Mus. Novitates 1559: 1–27.
Paula Couto, C. de (1962). Didelfideos fósiles del Paleoceno de Brasil. Rev. Mus. Argentino Cien. Nat. B. Rivadavia Zool. 112: 135–166.
Richter, L. L., and Frangi, J. L. (1992). Bases ecológicas para el manejo del bosque de Nothofagus pumilio. Rev. Fac. Agron. Buenos Aires 68: 35–52.
Sadler, P. M. (1988). Geometry and stratification of uppermost Cretaceous and Paleogene units on Seymour Island, northern Antarctic Peninsula. In: Geology and Paleontology of Seymour Island, Antarctic Peninsula, R. M. Feldmann and M. O. Woodburne, eds., pp. 303–320, Geol. Soc. Am. Mem. 169, Boulder, CO.
Simpson, G. G. (1948). The beginning of the Age of Mammals in South America. Part 1. Introduction. Systematics: Marsupialia, Edentata, Condylarthra, Litopterna, and Notioprogonia. Bull. Am. Mus. Nat. Hist. 91: 1–232.
Vizcaíno, S. F., and Scillato-Yané, G. J. (1995). An Eocene tardigrade (Mammalia, Xenarthra) from Seymour Island, West Antarctica. Antarctic Sci. 7(4): 407–408.
Vizcaíno, S. F., Carlini, A. A., and Reguero, M. A. (1988). Primer registro de un marsupial didelphimorphia en Antártida. Su implicancia biogeográfica. In: V J. Arg. Paleontol. Vertebra., pp. 30–31, La Plata.
Vizcaíno, S. F., Reguero, M. A., Marenssi, S. A., and Santillana, S. N. (1994). The fossil record of land mammals in Antarctica. In: XXI Polar Symposium, M. Zalewski (ed.), pp. 49–54, Warsaw.
Vizcaíno, S. F., Reguero, M. A., Goin, F. J., Tambussi, C. P., and Noriega, J. I. (1999a). Community structure of Eocene terrestrial vertebrates from Antarctic Peninsula. In: Paleógeno de América del Sur y de la Península Antártica, pp. 177–183, Asociación Paleontológica Argentina, Spec. Publ. 5, Buenos Aires.
Vizcaíno, S. F., Pascual, R., Reguero, M. A., and Goin, F. J. (1999b). Antarctica as background for mammalian evolution. In: Paleógeno de América del Sur y de la Península Antártica, pp. 199–209, Asociación Paleontológica Argentina, Spec. Publ. 5, Buenos Aires.
Woodburne, M. O., and Case, J. A. (1996). Dispersal, vicariance and the Late Cretaceous to early Tertiary land mammal biogeography from South America to Australia. J. Mammal. Evol. 3: 121–161.
Woodburne, M. O., and Zinsmeister, W. J. (1982). Fossil land mammal from Antarctica. Science 218: 284–286.
Woodburne, M. O., and Zinsmeister, W. J. (1984). The first land mammal from Antarctica and its biogeographic implications. J. Paleontol. 58: 913–948.
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Goin, F.J., Case, J.A., Woodburne, M.O. et al. New Discoveries of “Opposum-Like” Marsupials from Antarctica (Seymour Island, Medial Eocene). Journal of Mammalian Evolution 6, 335–365 (1999). https://doi.org/10.1023/A:1027357927460
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DOI: https://doi.org/10.1023/A:1027357927460