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Maastrichtian ammonites chiefly from the Prairie Bluff Chalk in Alabama and Mississippi

W. A. Cobban·W. J. Kennedy
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Abstract

The Prairie Bluff Chalk of Alabama and Mississippi yields a diverse ammonite fauna of Maastrichtian age. Twenty-eight species, of which three are new, are recorded herein: Pseudophyllites indra (Forbes, 1846), Hauericeras rembda (Forbes, 1846), Pachydiscus ( Pachydiscus ) maconensis n. sp., P. ( P. ) cf. gollevillensis (d'Orbigny, 1850), P. ( P. ) jacquoti (Seunes, 1890), P. ( P. ) egertoni (Forbes, 1846), Sphenodiscus lobatus (Tuomey, 1854), S. pleurisepta (Conrad, 1857), Coahuilites sheltoni Böse, 1928, Nostoceras ( Nostoceras ) alternatum (Tuomey, 1854), N. ( N. ) mendryki Cobban, 1974a, N. ( N. ) magdadiae Lefeld and Uberna, 1991, N. ( N. ) irregulare n. sp., Glyptoxoceras torquatum (Morton, 1834), Glyptoxoceras sp. A, Glyptoxoceras ? sp., Baculites lomaensis Anderson, 1958, Baculites spp. A–C, Eubaculites labyrinthicus (Morton, 1834), E. carinatus (Morton, 1834), Baculites ? trabeatus (Morton, 1834), Trachybaculites columna (Morton, 1834), Discoscaphites conradi (Morton, 1834), D. gulosus (Morton, 1834), Jeletzkytes criptonodosus Riccardi, 1983, Trachyscaphites alabamensis n. sp., and T. yorkensis (Stephenson, 1941). One genus, Trachybaculites , is new. The bulk of the fauna can be referred to a Discoscaphites conradi assemblage zone, but some elements in the fauna are significantly older.

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W. A. Cobban, W. J. Kennedy. 2017-08-11. Maastrichtian ammonites chiefly from the Prairie Bluff Chalk in Alabama and Mississippi. https://doi.org/10.1017/s0022336000061096

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