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A shell bed in the upper part of the Anaipadi Formation of the Trichiopoly Group near the villages of Pilimisai and Koothur in the Cauvery Basin, Tamil Nadu, south India yielded an abundant ammonite fauna assigned to the lower part of the Kossmaticeras (Kossmaticeras) theobaldianum Zone and to the lower Coniacian. The ammonite association of this interval in the Cauvery Basin is dominated by Mesopuzosia , Damesites , and Kossmaticeras (Kossmaticeras) species. The fauna is: Phylloceras (Hypophylloceras) masiaposensis (Collignon, 1956), Phyllopachyceras sp. , Tetragonites epigonus Kossmat, 1895, Gaudryceras (Gaudryceras) mite (Hauer, 1866), Mesopuzosia gaudama (Forbes, 1846), Damesites sugata (Forbes, 1846), Kossmaticeras (Kossmaticeras) theobaldianum (Stoliczka, 1865), K. (K.) recurrens (Kossmat, 1897, K. (K.) jonesi Collignon, 1965, Menabonites anapadensis (Kossmat, 1898), Lewesiceras sp., Placenticeras cf. kaffrarium Etheridge, 1904, Glyptoxoceras sp., and Scalarites sp. [ABSTRACT FROM AUTHOR]

Abstract: An integrated study of the ammonites, inoceramid bivalves, planktonic foraminifera, calcareous nannofossils, geochemistry, stable carbon isotopes, and cyclostratigraphy is provided for the upper Middle to upper Upper Albian sucession exposed in the Col de Palluel section east of Rosans in Hautes-Alpes, France. The Albian-Cenomanian boundary interval described by Gale et al. at Mont Risou is re-examined, a total thickness of 370 m of the Marnes Bleues Formation. Zonal schemes based on ammonites, inoceramid bivalves, planktonic foraminifera, and calcareous nannofossils are integrated with the stable carbon isotope curve and key lithostratigraphic markers to provide a sequence of more than 70 events in the uppermost Middle Albian to basal Cenomanian interval. Time series analysis of the Al2O3 content of the 500 m Albian sequence present in the Col de Palluel and Risou sections reveals the presence of the 20 kyr precession, 40 kyr tilt, 100 kyr short eccentricity, and 406 kyr long eccentricity cycles. Correlation using planktonic foraminiferan and nannofossil data provide a link between the Col de Palluel and Risou sections and the Italian sequence at Gubbio, and in the Piobbico core. This provides a basis for the extension of the orbital time scale of Grippo et al. to the sequence. It reveals a major break in the Col de Palluel succession at the top of the distinctive marker bed known as the Petite Vérole that may represent as much as 2 Ma. It also provides a basis for the estimation of the length of the Albian Stage at 4.12Ma, 0.8 Ma for the early Albian, 2.84 Ma for the Middle Albian, and 3.68 Ma for the late Albian substages. [Copyright &y& Elsevier]

Abstract: Ammonites of the Albian genera Brancoceras, Dipoloceras, Mortoniceratoides and Neophlycticeras are described and illustrated for the first time from Ecuador. Precise stratigraphic distribution in the Rio Misahuali field section allows delineation of the Middle/Upper Albian boundary in the Oriente of Ecuador through the recognition of the Dipoloceras cristatum Zone. [Copyright &y& Elsevier]

Abstract: The ammonite faunas of the Main Street Limestone, Grayson Marl and Del Rio Clay form the basis for a revised upper Upper Albian to lower Lower Cenomanian zonal sequence in northeast Texas. A Mortoniceras (Subschloenbachia) rostratum Zone, previously known to be well-represented in the Denton Clay, Weno Limestone, and Pawpaw Shale, extends into the lower Main Street Limestone. A M. (S.) perinflatum Zone is also recognised in the Main Street on the basis of the occurrence of the index species, although precise stratigraphic relations of the scattered records of the two index species are not known. The succeeding Mariella (Wintonia) brazoensis Zone is an Acme Zone, yielding a monospecific assemblage of the zonal index that is abundant in the Main Street Limestone, although the index species ranges both lower and higher in the sequence. The base of the Cenomanian, in ammonite terms, is drawn at the base of the succeeding Graysonites adkinsi Zone, on the basis of the first occurrence of Mantelliceratinae with inner and outer ventrolateral tubercles. The index species of the succeeding G. wacoensis Zone is the senior synonym of Graysonites lozoi Young, 1958, and G. wooldridgei Young, 1958. The Lower Cenomanian sequence is generally truncated by the erosive base of the terrigenous-clastic Woodbine Formation in the study area, but relics of Buda Limestone, and of Grayson Marl with ammonites of the upper Lower Cenomanian Budaiceras hyatti Zone are present locally in Denton and Grayson Counties. A total of 30 ammonite species are described, of which Moremanoceras flexuosum, Stoliczkaia (Stoliczkaia) conlini, and Neophlycticeras (Neophlycticeras) fascicostatum are new. [Copyright &y& Elsevier]

Abstract: The lower part of the Pawpaw Shale in northeast Texas yields an abundance of diminutive limonitic ammonites, the assemblage being: Tetragonites sp. juv., Engonoceras serpentinum (Cragin, 1900), Conlinites wrighti gen. et sp. nov., Cantabrigites wenoensis (Adkins, 1920), Neophlycticeras (Neophlycticeras) sp., Neophlycticeras (Paradolphia) occidentalis sp. nov., Stoliczkaia (Stoliczkaia) clavigera Neumayr, 1875, Stoliczkaia (Lamnayella) worthense (Adkins, 1920), Stoliczkaia (Shumarinaia) asiatica Matsumoto and Inoma, 1975, Enigmaticeras riceae gen. et sp. nov., Flickia simplex Pervinquière, 1907, Ficheuria pernoni Dubourdieu, 1953, Ficheuria americana sp. nov., Anisoceras armatum (J. Sowerby, 1817), Hamites venetzianus Pictet, 1847, Mariella (Mariella) worthensis (Adkins and Winton, 1920), Mariella (Mariella) asper sp. nov., Lechites (Lechites) comanchensis (Adkins, 1920), Worthoceras worthense (Adkins, 1920), and Scaphites hilli Adkins and Winton, 1920. This assemblage is correlated with the Mortoniceras (Subschloenbachia) rostratum Subzone of the European sequence on the basis of the occurrence of that species in the underlying Weno Limestone, in the passage beds between the Pawpaw Shale and the succeeding Main Street Limestone, and the lower part of the Main Street. Some previous authors have interpreted the diminutive limonitic ammonites of the Pawpaw as being “dwarf” or “stunted”. The overwhelming majority of individuals are nuclei of much larger ammonites, with smaller numbers of adults of small species that occur in other facies and geographic locations, together with a smaller number still of paedomorphic dwarfs. The fauna is interpreted as a preservational one, where diagenetic pyrite formed in relatively small voids, either the early phragmocone chambers of larger ammonites, or the phragmocone and body chambers of genuinely diminutive species which oxidised to limonite during the weathering process. [Copyright &y& Elsevier]

A specimen of the Late Turonian marker ammonite Prionocyclus germari (Reuss, 1845) is recorded from the upper Nodular Limestone of the Bagh Beds sequence of the Hatni River section near Kukshi, Madhya Pradesh Province, India. A reappraisal of previous ammonite and inoceramid records from the sequence shows that these are all compatible with a Late Turonian date for the upper Nodular Limestone. The higher parts of the Bagh Beds are thus securely dated as Late Turonian to Coniacian on ammonite and inoceramid evidence. [Copyright &y& Elsevier]