In the Dinarides, a series of long-lived lakes, known as the Dinarides Lake System (DLS) developed during the Miocene. The Sinj Basin, situated in southern Croatia, is one of the best studied among them, providing valuable insights into the paleogeographic evolution of the region. Previous research established a chronostratigraphic framework in the NW part of the basin using paleomagnetic data calibrated by 40Ar/39Ar dating. Subsequent studies demonstrated that lacustrine flooding was diachronous. However, the influence of the Miocene Climatic Optimum (MCO) or the regional Miocene extensional tectonics is still debated. This study provides new constraints on the evolution of the Sinj Basin by integrating previous dating results with new LA–ICP–MS U–Pb–zircon dating of volcaniclastic and residual deposits from the NW, central, and SE parts of the basin. The obtained U-Pb ages range between 17.7 and 15.3 Ma and provide new constraints on the timing of initial lacustrine flooding. Correlation with the MCO suggests a close relationship between climate change and lacustrine development. Lake-level falls reflected by conglomerates and coals deposited in marginal and more distal parts of the basin, respectively, suggest environmental instability after 15.3 Ma, towards the end of the MCO. Detrital zircon grains reveal a wide spectrum of ages from the Neoproterozoic to the Early Miocene, suggesting multiple redeposition cycles, starting with the Cadomian and Variscan orogenies, followed by Cretaceous–Oligocene uplift of the Dinarides, and the recycling of foreland basin deposits into the Miocene Sinj Basin. Finally, this study demonstrates the usefulness of LA–ICP–MS U–Pb dating for the reconstruction and correlation of isolated intramontane basins.
Coastal systems, such as those of the Eastern Adriatic Coast, are complex archives where marine and terrestrial influences can hinder paleoclimate reconstruction. Here, we present a new lake sediment record from coastal karst Lake Velo Blato and use stable isotopes and compositional analysis of ostracod assemblages to reconstruct Holocene paleoclimate and paleoenvironmental changes. Ostracod assemblages revealed three ecological groups: brackish (Cyprideis torosa), freshwater (Cypridopsis vidua), and wetland (Limnocythere inopinata, Darwinula stevensoni), indicating that salinity is the main ecological driver, while processes related to lake succession are secondary. Stable isotope composition of calcite suggests the wettest climate conditions between 8100 and 7500 cal yr BP, coinciding with the development of a freshwater lake. Marine influence is evidenced between 7500 and 6300 cal yr BP, marked by a transition from freshwater (Candona neglecta, Cypridopsis vidua, Paralimnocythere psammophila) to brackish (Cyprideis torosa, Candona angulata, Heterocypris salina) ostracod assemblages, which persisted throughout the Middle to Late Holocene. However, shifts in carbon isotopes around 2100 cal yr BP indicate a significant environmental change, coinciding with a transition from a brackish lake to a shallow wetland. Climatically, warm and dry conditions prevailed during the Roman and Medieval Warm Periods, while wetter conditions have dominated since the Little Ice Age. This study provides a high-resolution record of Holocene paleoclimate and paleoenvironmental change, offering a valuable contribution to understanding coastal systems of the Eastern Adriatic region.
Lake sediments from the Dinaric karst region (Central Mediterranean) hold valuable paleoenvironmental records, yet remain underexplored compared to other Mediterranean areas. This study presents a multiproxy analysis of Holocene paleolake sediments from Prolosko Blato karst wetland in Dalmatia (Croatia), using geochemistry, ostracods, and radiocarbon dating to reconstruct past hydroclimate variability. Proxy records indicate intermittent lake conditions during the wetter Early Holocene, contrasting with other lake level records, probably due to high surface and subsurface connectivity in the karst. The Middle to Late Holocene is characterized by lake deepening and lacustrine carbonate sedimentation, decreased run-off and increased ostracod abundances, indicating the development of permanent lake conditions. The oxygen and carbon isotope data suggest progressive aridification towards the Late Holocene, in line with other Mediterranean records. However, a pronounced shift to lower isotope values between 2100 and 500 cal yr BP indicates wetter conditions in the lake, in contrast to the lower lake levels and more arid conditions reported for the Roman and Medieval Warm Periods in other Mediterranean records. The sudden shift was linked to the opening of a sinkhole in the paleolake's marginal part, which caused hydrological disturbance and the formation of a modern, seasonally flooded wetland. This research provides a new Holocene hydroclimate record for the Dinarides, while highlighting the influence of geomorphological processes in karst on paleoclimate interpretation.
The cockroach Praeblattella VR & Scaron;ANSK & Yacute;, 2003 is a cosmopolitan genus recorded from the Mesozoic localities of Japan, Mongolia, the Russian Federation, South Korea, Thailand, Myanmar, Kazakhstan, Mongolia, India and USA, ranging in age from the Oxfordian to the Campanian (Late Jurassic to Late Cretaceous). Until now, two species were described from the amber of Cretaceous age, from North Myanmar Praeblattella patrickmuelleri & Scaron;M & Iacute;DOV & Aacute; in & Scaron;M & Iacute;DOV & Aacute;, BRUTHANSOV & Aacute; & HAIN, 2024 and Praeblattella continuosa & Scaron;M & Iacute;DOV & Aacute; in & Scaron;M & Iacute;DOV & Aacute;, BRUTHANSOV & Aacute; & HAIN, 2024. A new species from Myanmar amber, Praeblattella aliciae sp. nov. is described here, with characteristic pale forewing longitudinal colouration (including distinct dark maculae) and a venation scheme typical for the genus. The geographic distribution of Praeblattella fossil specimens is also given. Due to its high level of preservation in amber, this new species expands the fossil record and contributes to a better understanding of the morphology of this cockroach genus. It is unique in revealing characteristics transitional to its descendant family, the Ectobiidae.
