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RESEARCH PRODUCT

Taxonomic revision of two Mesozoic ammonites collections housed at the "G.G. Gemmellaro" Museum (Palermo, Sicily).

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Two historical collections of Mesozoic ammonites from the Tardàra Mountain (SO Sicily), housed in the “Gaetano Giorgio Gemmellaro” Museum of the University of Palermo, have been revised in this paper. The former and the older collection, studied by Mariano Gemmellaro in the 1919, it is composed of 27 specimens, attributed to 5 genera. All the taxa studied by the Author were referred to the Middle Jurassic, Macrocephalites macrocephalus Zone (early Callovian stage). The second collection, studied by Francesco Bruno in the 1954, consists of 46 specimens attributed to 13 genera. The species identified by Bruno were referred to a chronostratigraphic range spanning from Callovian to Tithonian (Middle-Upper Jurassic). The taxonomic analysis of both historical collections has led to extend, for some taxa, the chronostratigraphic range known from literature and to identify the presence of taxa rarely reported in Sicily until now, including Spiticeras pseudogroteanum Djanélidzé, 1922 and Fauriella gr. boissieri (Pictet, 1867) classically referred to the Lower Cretaceous (Berriasian). Also the determination, in the Bruno Collection, of specimens such as Neolissoceras cf. grasianum (d’Orbigny, 1841), Jabronella sp. and Kilianella sp. clearly indicates the presence of a register referable to the Early Cretaceous, rarely represented in Sicily. In conclusion, the study of the collections already mentioned has shown, for the Mariano Gemmellaro Collection, a prevalence of species and genera stratigraphically attributable to the Middle Jurassic (Bajocian-Callovian) while in the Bruno Collection genera and species are more related to the Upper Jurassic-Lower Cretaceous interval.