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The endorheic nature of Lake Trasimeno in combination with its position in central Italy makes it a relevant site to better constrain spatial differences in Holocene climatic variability in the Mediterranean area. Herein, we present a high-resolution ostracod record from the Holocene section of an 8.59-m-long sedimentary core, which is compared with historical data to distinguish anthropogenic and climatic signals. The occurrence, abundance and vanishing of ostracod species are directly controlled by lake-level variations, which are in turn related to global and regional climatic changes (i.e. moisture variations). The total organic carbon content as well as observed lithological changes provide additional information about Lake Trasimeno's hydrological and trophic conditions in the past. Most important variations have been identified at ca. 10,000 cal. yr BP, when the lacustrine basin changed from a temporary to a permanent waterbody (from Sarsicypridopsis aculeata to Candona angulata association). The highest lake level and the total absence of ostracods occur at around 9000 cal. yr BP. The recorded humid phase persisted up to ca. 4200 cal yr BP since when a lake-level decreasing trend started and continued until the present day (Candona angulata, Cyprideis torosa and Darvinula stevensoni associations). The frequency of changes in the relative abundance of the main species shows centennial variations (i.e. C. angulata, C. torosa and Darvinula stevensoni). As historical evidences yield that human interventions to control the lake level remained unsuccessful in the past, Lake Trasimeno records an almost pristine climatic signal during most of the Holocene, which is quite unusual in the highly populated Mediterranean area. [ABSTRACT FROM AUTHOR]

The Tiberino Basin is a wide Plio-Pleistocene intermountain basin located in central Apennine (central Italy). Its sedimentary infill is made of a thick succession of Pliocene-early Quaternary continental deposits, the oldest of which can be referred to the Fosso Bianco Formation, composed of grey clays deposited in a huge (at least 500 km²) and relatively deep (not less than 50 m) lake, the Palaeolake Tiberino. We analyse the lacustrine ostracod assemblages from the Fosso Bianco Formation and provide descriptions of five new species included in the subfamily Candoninae (Caspiocypris basilicii sp. nov., Caspiocypris perusia sp. nov., Caspiocypris posteroacuta sp. nov., Caspiocypris tiberina sp. nov. and Caspiocypris tuderis sp. nov.)) and one new species included in the subfamily Limnocytherinae (Paralimnocythere umbra sp. nov.)). The five species of Caspiocypris seem to represent a species flock, i.e. Caspiocypris includes a group of closely related species characterized by monophyly, endemism and speciosity, confirming the 'ancient lake' nature of the Palaeolake Tiberino during the Piacenzian-Gelasian. The ostracod assemblage points to a relatively deep-water and low energy lacustrine environment marked by a high level of endemism. [ABSTRACT FROM AUTHOR]

Work on thermal pools at Poggetti Vecchi in Grosseto, Italy, exposed an up to 3-meter-thick succession of seven sedimentary units. Unit 2 in the lower portion of the succession contained vertebrate bones, mostly of the straight-tusked elephant, Palaeoloxodon antiquus, commingled with stone, bone, and wooden tools. Thermal carbonates overlying Unit 2 are radiometrically dated to the latter part of the middle Pleistocene. This time span indicates that early Neanderthals produced the human artifacts from Poggetti Vecchi. The elephant bones belong to seven individuals of different ages. Sedimentary facies analysis and paleoecological evidence suggest a narrow lacustrine-palustrine embayment affected by water-level fluctuations and, at times, by hydrothermal water. Cyclic lake-level variations were predominantly forced by the rapid climatic fluctuations that occurred at Marine Isotope Stage (MIS) 6–7 transition and throughout the MIS 6. Possibly an abrupt, intense, and protracted cold episode during the onset of MIS 6 led to the sudden death of the elephants, which formed an unexpected food resource for the humans of the area. The Poggetti Vecchi site adds new information on the behavioral plasticity and food procurement strategies that early Neanderthals were able to develop in Italy during the middle to the late Pleistocene transition. [ABSTRACT FROM PUBLISHER]

A multiproxy approach in a sediment core from Lake Trasimeno has been used to reconstruct the climate history of central Italy during the Late Pleistocene to Early Holocene period (ca. 47,000–9,000 cal yr B.P.). Ostracod assemblages and sedimentological data (lithology and carbonate content) have been used to infer past hydrological changes in the area. Ostracods were analyzed throughout the core using diversity indexes and multivariate statistic analyses (Cluster and PCA). Three main associations linked to lake level and salinity variations were recognized: 1) the C. torosa association, indicating permanent lacustrine conditions with high lake levels and low salinities; 2) the S. aculeata association, linked to very shallow/temporary waters with higher salinity conditions; and 3) the S. aculeata - E. mareotica association pointing to temporary water conditions and the highest salinities. Furthermore, the presence of C. fuscata and L. blankenbergensis during wide parts of the Late Pleistocene indicates temperatures lower than present days. Alternations of these three ostracod associations compares well with the oxygen isotope curve from Greenland (NGRIP) and are thus interpreted as climatically driven. At the Holocene transition (Termination 1), the ostracod associations indicate a delay in the increasing warming and humidity with respect to the NGRIP temperature record. [ABSTRACT FROM AUTHOR]

Biochronology is the most widely used method for organizing the successions of continental vertebrate faunas in geological time and for allowing the correlation of continental deposits. However, due to the fragmentary nature of the paleontological record and the diachronicity of first and last occurrences of vertebrate taxa in different areas (i.e., bioevents), it is difficult to precisely define the temporal boundaries between biochronological units. That is why it is crucial to calibrate biochronological data with independent proxies wherever possible. Here, thanks to an interdisciplinary approach that combines sedimentology and stratigraphy, vertebrate paleontology, micropaleontology (ostracods), palynology, and geochronology, we provide a chronological framework and a paleoenvironmental reconstruction of the paleontological site of Pantalla (Central Italy). The combination between biochronological/biostratigraphic and geochronological (U-series/ESR dating and paleomagnetism) data allows us to refer the site to c. 2.2 Ma, i.e., in the transition phase between the Middle and Late Villafranchian in the European biochronological scheme. We reconstruct the environment as a fluvial area with a frequently flooded wet floodplain and marked (probably seasonal) variations of the water level of the channel river. The depositional system was surrounded by a conifer-dominated forest, which is suggestive of a glacial phase. • Pantalla is a paleontological site yielding well-preserved terrestrial mammals. • Geological and paleontological data are combined in an interdisciplinary approach. • A chronological and paleoenvironmental framework of Pantalla is provided. • Age of the site (c. 2.2 Ma) is close to the Middle-Late Villafranchian transition. • The environment was a fluvial area with a frequently flooded wet floodplain. [ABSTRACT FROM AUTHOR]