Lower Pliocene molluscs from southern Tuscany (Italy)
Dominici, S.; Forli, M. (2021). Lower Pliocene molluscs from southern Tuscany (Italy). Boll. Soc. Paleont. Ital. 60(1): 69-98
In: Bollettino della Societa Paleontologica Italiana. Società Paleontologica Italiana: Modena. ISSN 0375-7633, meer
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| Trefwoorden |
Muricidae Rafinesque, 1815 [WoRMS]
Marien/Kust |
| Author keywords |
Biodiversity, facies analysis, Mediterranean benthos, Zanclean, Muricidae |
| Abstract |
Benthic mollusc assemblages of shallow marine successions host a large part of known biodiversity of past marine ecosystems. Important as they are to understand community assembly of the Mediterranean benthos after the Messinian Salinity Crisis and during the late Pliocene and Quaternary climatic change, onshore facies are little represented in an otherwise thick lower Pliocene record. Strata outcropping in the Val d’Orcia and Cinigiano-Baccinello Basins, in southern Tuscany, are instead rich with shell beds from brackish water and other shallow marine environments, offering a means to approach the study of the biodiversity of coastal settings and a base level to understand the macroevolutionary response of the Mediterranean biota to ennvironmental and climate change. These Zanclean-lower Piacenzian successions are here correlated based on available biostratigraphic data and on the study of the stacking pattern of nearshore and open shelf sedimentary facies. New quantitative data and the review of available literature allow to explore the composition and structure of six recurring assemblages of benthic molluscs, aligned on an ideal onshore-offshore gradient. A review of the distribution of the six facies types in different Zanclean and early Piacenzian basins across the Mediterranean, collected in the literature data and with the uncertainty deriving from the fragmentary nature of the available choronostratiphic framework, confirms that there are gaps of the record. A taxonomic review of some Gastropoda, including rare species and species never reported before in southern Tuscany, is proposed. New species Prososthenia esuegirottii and new subspecies Chicoreus (Triplex) michelottii pliotrivaricosus are described, the second compared to conspecific material from the Spanish Pliocene and other strictly allied forms. The significance of Helminthia triplicata (Brocchi, 1814) and Hexaplex (Trunculariopsis) trunculus neomagensis (Fontannes, 1882) is discussed. |
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