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Sample records for arcoscalpellum michelottianum seguenza

  1. NUCINELLA ALIBRANDI (CONTI, 1864 AND N. SEGUENZAE (DALL, 1898,THE LAST EUROPEAN NUCINELLIDS (BIVALVIA, PROTOBRANCHIA

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    RAFAEL LA PERNA

    2004-07-01

    Full Text Available The revision of the genus Nucinella Wood, 1851 from the Italian Pleistocene led to the identification of two species, Nucinella alibrandi (Conti, 1864 and N. seguenzae (Dall, 1898. The former is from the continental shelf deposit of Monte Mario (Rome, the latter from upper slope deposits in Southern Italy (Calabria and Messina. The two species are very similar to each other and differ mainly in the anterior features of hinge. The peculiar hinge of Nucinella is examined in detail and its ontogenetic changes are reported. The Tertiary to Quaternary palaeobiogeographic history of Nucinella in the European area proves the Tethyan origins of this genus. Since the closure of the seaway to the Indo-Pacific in the Early Miocene, Nucinella survived in the European waters as a Tethyan relict until the Plio-Pleistocene, when cooling caused its definitive disappearance. N. alibrandi and N. seguenzae are the last representatives of the genus in the European waters.

  2. PLEISTOCENE BATHYAL MOLLUSCAN ASSEMBLAGES FROM SOUTHERN ITALY

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    ITALO DI GERONIMO

    1997-11-01

    Full Text Available Four Pleistocene bathyal molluscan assemblages from southern Italy (Calabria and Messina area were studied. One hundred and thirty-six species were recorded. Twenty-four were classified and described in detail and thirty-five were illustrated. The following new combinations are pro posed: Solariella marginulata (Philippi, 1844, Iphitus tenuisculptus (Seguenza, 1876, Benthomangelia tenuicostata (Seguenza, 1879, Chrysallida microscalaria (Seguenza, 1876, Ennucula corbuloides (Seguenza, 1877, Ennucula rotundata (Seguenza, 1877, Thestyleda cuspidata (Philippi, 1844, Katadesmia confusa (Seguenza, 1877, Austrotindaria pusio (Philippi, 1844, Austrotindaria salicensis (Seguenza, 1877. Comments concerning the taxonomy of Fissurisepta Seguenza, 1862, Solariella Wood, 1842, Ennucula Iredale, 1931, Thestyleda Iredale, 1929, Ledella Verrill & Bush, 1897, Yoldiella Verrill & Bush, 1897, Bathyspinula Filatova, 1958, Katadesmia Dall, 1908, Austrotindaria Fleming, 1948 and Cadulus Philippi, 1844 are included. The assemblages are dominated by nuculoids and fit the general compositional pattern of the deep-sea molluscan communities. A paleodepth of 500-600 m is inferred for two assemblages, whereas a greater depth, pro bably not exceeding 1,000 m, is suggested for the other two. Taxonomic affinities with northeast Atlantic and more generally with World Ocean deep-sea molluscan faunas are remarkable. The Plio-Quaternary evolution of the deep Mediterranean benthos is discussed.    

  3. PROPOTAMOCHOERUS SP. (SUIDAE, MAMMALIA FROM THE LATE MIOCENE OF GRAVITELLI (MESSINA, SICILY, ITALY REDISCOVERED

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    GIANNI GALLAI

    2006-07-01

    Full Text Available This paper describes two casts of a suid from the Late Miocene of Gravitelli (Messina, Sicily, originally described by Seguenza in 1902. The entire Gravitelli faunal collection was lost in the early 1900¡¦s. The recent rediscovery of two casts in the collections of the Museo di Storia Naturale of the University of Florence represent the only available material from this locality (in addition to the original description and illustration by Seguenza. The study of these casts allow a revision of the Gravitelli suid and its attribution to the genus Propotamochoerus. Although a specific determination is not possible, we suggest probable affinities with the species P. hysudricus or P. provincialis.

  4. Mg/Ca temperature calibration for the benthic foraminifers Bulimina inflata and Bulimina mexicana

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    Grunert, Patrick; Rosenthal, Yair; Jorissen, Frans; Holbourn, Ann

    2016-04-01

    Bulimina inflata Seguenza 1862 and Bulimina mexicana Cushman 1922 are cosmopolitan, shallow infaunal benthic foraminifers which are common in the fossil record throughout the Neogene and Quaternary. The closely related species share a similar costate shell morphology that differs in the presence or absence of an apical spine. In the present study, we evaluate the temperature dependency of Mg/Ca ratios of these species from an extensive set of core-top samples from the Atlantic and Pacific oceans. The results show no significant offset in Mg/Ca values between B. inflata, B. mexicana, and two other costate morphospecies when present in the same sample. The apparent lack of significant inter-specific/inter-morphotype differences amongst the analysed costate buliminds allows for the combined use of their data-sets for our core-top calibration. Over a bottom-water temperature range of 3-14°C, the Bulimina inflata/mexicana group shows a sensitivity of ˜0.12 mmol/mol/°C which is comparable to the epifaunal Cibicidoides pachyderma and higher than for the shallow infaunal Uvigerina spp., the most commonly used taxa in Mg/Ca-based palaeotemperature reconstruction. B. inflata and B. mexicana might thus be a valuable alternative in mesotrophic settings where many of the commonly used species are diminished or absent, and particularly useful in hypoxic settings where costate buliminds may dominate foraminiferal assemblages. This study was financially supported by the Max-Kade-Foundation and contributes to project P25831-N29 of the Austrian Science Fund (FWF).