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La Sous-Famille des Taramelliceratinae (Ammonitina, Haploceratoidea, Oppeliidae) de l'Oxfordien moyen et supérieur (Zone à Plicatilis, Sous-Zone à Vertebrale - Zone à Bimammatum, Sous-Zone à Berrense) du Nord de la Vienne, France (Province subméditerranéenne) [Subfamily Taramelliceratinae (Ammonitina, Haploceratoidea, Oppeliidae) from Middle and Upper Oxfordian strata (Plicatilis Zone, Vertebrale Subzone - Bimammatum Zone, Berrense Subzone) of N Vienne, France (submediterranean province)]

Keywords: Ammonitina , Taramelliceratinae , Taramelliceras , Creniceras , Proscaphites , Richeiceras , Metahaploceras , distribution stratigraphique , Oxfordien moyen et supérieur , domaine téthysien , Poitou , France

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Abstract:

In the area of northern Poitou studied Taramelliceratinae are present at every level except in the Schilli Subzone, itself possibly absent, and the Stenocycloides Subzone in which only Perisphinctidae and Trimarginites sp. occur. Although some species are known and cited in the literature often, they are figured infrequently or not at all: Taramelliceras (Taramelliceras) dentostriatum (Quenstedt), T. (T.) callicerum (Oppel), T. (Proscaphites) anar (Oppel). Here, the ranges of these species in the stratigraphic succession were determined through their association with other faunas in the same collections, using the presence or absence of known precise stratigraphic markers (for example: Neomorphoceras chapuisi (Oppel) = Transversarium Zone, Luciaeformis Subzone ; Taramelliceras (? Taramelliceras) colleti (Lee) = Rotoides Subzone ; "Epipeltoceras semimammatum" (Quenstedt) = Bimammatum Zone, "Berrense" Subzone, Semimammatum horizon) and/or the disappearance of species with longer ranges (for example: the disappearance of Neoprionoceras lautlingensis (Rollier) which is present in the Parandieri Subzone, but absent in the overlying Luciaeformis Subzone). The ranges of certain species that had been incorrectly located stratigraphically : T. (T.) dentostriatum (Quenstedt), T. (T.) callicerum (Oppel), T. (T.) externnodosum Dorn, have been restored to their true location as determined from their occurrences in the author's collections and in those of other collectors who had noted their stratigraphic relationships to other taxa.It is recommended that the date of creation of the Luciaeformis Subzone and the Nectobrigensis, Luciaeformis and Subschilli horizons (Middle Oxfordian, Transversarium Zone) should be rectified. Currently, these are indicated as having been created in 1984. However, if the author's name, G. Melendez, is correct the date of their creation cannot have been 1984, the year in which the G. Melendez thesis was defended, for the manuscript was published only in 1989. It is also proposed that the Duongi horizon Melendez, 1989, be renamed as the Duongae horizon Melendez, 1989, because the index form, Perisphinctes (Dichotomoceras) duongi Melendez, 1989, is an ammonite species named to honor of A.N. Duong, a woman.The study involved more than fifteen hundred individuals, all collected in the zone investigated. Only the most representative are figured here. The poor state of preservation of the ammonites (encrusted, often worn on one face, with the umbilicus not accessible) did not permit measurement (hence no table) except that of the diameter and so

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