Biostratigraphic Indicators Research Articles

The Carboniferous spore genus Vestispora: New palynological insights from Gondwana

Palynological studies from Europe and North America have repeatedly considered the Carboniferous miospore genus Vestispora a useful biostratigraphic indicator, resulting in a detailed review and discussion of its variable morphotypes. This was not the case in Gondwana, where Vestispora has rarely been reported. However, a few studies from India and South America used the absence of this taxon as an argument for a Permian age.The present work introduces a well-preserved and diverse record of five species of Vestispora from the Pennsylvanian (Moscovian-Gzhelian) of the Dhiffah Formation, north Western Desert (NWD), Egypt. Moreover, a detailed review of previous records of Vestispora was introduced in a trial to understand its regional distribution in Gondwana. It turned out that Vestispora is restricted to the Tethyan realm or the vegetation belt stretching North of Gondwana. However, the genus seems to exhibit a wider stratigraphic range in the Tethyan realm of Gondwana than in the Euramerican Province, with the youngest occurrences up to the top of the Carboniferous.

Anthropogenic structure emplacement and sediment transport at King Herod's harbour, Israel: ED-μXRF (Itrax) data and foraminifer Pararotalia calcariformata as proxies of coastal development over millennia

The construction of harbours along high energy nearshore environments, which commonly include the emplacement of hard structures both as central features (e.g., piers, jetties) as well as protective measures (e.g., wave breakers, coastal armouring), can alter coastlines in a multitude of ways. These include reconfiguring the coast's morphology, introducing or redistributing exogenous and endogenous materials, and changing localized environmental substrate and structural conditions; and, as a result, impact the associated ecological communities. With growing coastal populations and associated coastal development, concerns over the long-term consequences of such projects are of global interest. Caesarea Maritima, a large-scale, artificially constructed ancient harbour built between 21 and 10 BCE, provides a rare opportunity to address these impacts and investigate its fingerprint on the landscape over 2000 years. To approach this, representative sediment samples were isolated and analyzed from two sediment cores (C1, C2), an excavated trench (W), and a sample of ancient harbour construction material (aeolianite sandstone and hydraulic concrete; COF). Geochemical (Itrax μXRF, magnetic susceptibility) and foraminifera analyses were conducted and results from both methods were statistically grouped into significantly similar clusters. Results demonstrated the increased presence of aeolianite-associated elemental contributions only after the construction of Caesarea as well as in particularly high concentrations following previously proposed tsunami events, during which shallower and deeper materials would have been transported and redeposited. The foraminifera data shows the appearance and eventual abundance dominance of Pararotalia calcariformata as an indicator of coastal hardening. Results suggest that they are an especially well-suited species to demonstrate changing environmental conditions existing today. In previous studies, this species was mistakenly presented as a recent Lessepsian arrival from the Red Sea, when in fact it has had a long history as an epiphyte living on hardgrounds in the Mediterranean and co-existencing with humans and their harbour-building habits. Specimens of P. calcariformata, therefore, are useful indicators for the timing of harbour construction at Caesarea and may be used as rapid and cost-effective biostratigraphic indicators on sandy nearshore coastline in future geoarchaeological studies. This has implications for future studies along the Israeli coast, including both paleoenvironmental and modern ecological assessments.

A new model for Early Paleozoic ichnostratigraphy based on trace fossil assemblages from Brazil

Trace fossils are not generally utilized as biostratigraphic indicators due to their long stratigraphic ranges. Despite the use of intricate behavioral traces in the absence of other indicators, existing models like the Precambrian–Cambrian boundary and Cruziana stratigraphy encounter limitations due to crucial data gaps and regional constraints. To surmount these challenges, in this paper, we critically assess established models and present a new framework for Early Paleozoic strata, drawing on trace fossils from the intracratonic basins of Brazil. Our ichnostratigraphic model is calibrated using ichnological data from the Parnaíba, Paraná, and Amazonas basins, including new data. The analysis focuses on trace fossils in strata that are independently dated using chitinozoan, miospore, and acritarch biozonation. Key ichnotaxa, such as Arthrophycus and Cruziana, are identified as prominent indicators of the Llandovery Stage in Brazil. Occurrences of Heimdallia and Musculopodus in the Tianguá Formation also may be used to suggest a Llandovery interval. Notably, Bifungites, found widely across Brazilian basins, emerges as a potential ichnomarker for the Early to mid-Paleozoic interval, with a global presence throughout Cambrian to Mississippian deposits. While current ichnostratigraphic models lack robust calibration with chronostratigraphic or biostratigraphic data, our new proposed model integrates key ichnotaxa, including Bifungites, Climactichnites, Heimdallia, Oldhamia, and Musculopodus, surpassing those pre-existing zonations based on Cruziana and arthrophycids. These ichnotaxa exhibit unique features and narrow temporal ranges, meeting essential biostratigraphic criteria. Although their spatial distribution is somewhat limited, our new model, which is continually evolving with new data, holds promise for enhancing global stratigraphic correlations, particularly where independent age information is available.

Conodont biostratigraphy of a Carboniferous–Permian boundary section in siliceous successions of pelagic Panthalassa revealed by X-ray computed microtomography

Pelagic deep-sea siliceous successions in accretionary complexes preserve precious records of a vast deep seafloor that is now lost due to plate subduction. Microfossils are the key means of age assignment of these successions, but poor preservation due to tectonic deformation and metamorphism at the subduction zone hamper biostratigraphic records. X-ray computed microtomography, while not widely used in biostratigraphic studies until now, allows us to visualize fossils that are impossible or difficult to extract from host rocks due to poor preservation. In this study, we applied this method on conodonts from a pelagic chert–claystone succession in Okoshizawa, Iwaizumi Town, Northeast Japan, using a laboratory-based X-ray microscope. This work is a first close look at conodont biostratigraphy across the Carboniferous–Permian boundary in pelagic deep Panthalassa. We identified conodonts including ten species that are used as zonal markers in intensely studied areas such as around the East European Platform and Midcontinent United States. Based on the occurrence of conodonts, the studied section in Okoshizawa was correlated to the lower Moscovian to middle Artinskian. Confirmation of Moscovian to Artinskian age diagnostic conodonts from pelagic Panthalassa strengthens their role as global biostratigraphic indicators. By identifying more numerous specimens compared to the conventional hydrofluoric acid dissolution method, we were able to obtain information about conodont faunal characteristics around the Carboniferous–Permian boundary in pelagic deep areas of Panthalassa. The dominant taxa changed from Streptognathodus to Mesogondolella in the middle Asselian, probably reflecting an ecological takeover by the latter in the deep waters.

The Lower - Middle Miocene transition (Karpatian – Badenian) in the Krems Embayment (Central Paratethys, Lower Austria): a multistrati-graphic approach and the role of the Diendorf-Boskovice Fault System.

Abstract The Krems Embayment contains the westernmost fully marine depositional environments of the Karpatian and Bade-nian transgressions in the Central Paratethys. Four drill cores were investigated to analyse the bio- and lithostratigraphic, and tectonic relations. The investigated core sections cover the Karpatian Laa Formation (bio-zones M4, NN4) and the Badenian Gaindorf Formation (M5b-M6, NN4-NN5). Important biostratigraphic indicators identified are Praeorbulina glomerosa glomerosa, Praeorbulina glomerosa circularis and Orbulina suturalis for the Gaindorf Formation. The Laa Formation is indicated by the absence of Praeorbulina, Orbulina and Globigerina falconensis, low numbers of Globorotalia bykovae, and a prominent peak in Helicosphaera ampliaperta abundance at the end of the Karpatian. Cibicidoides lopjanicus and Cassigerinella spp. occur with high percentages in Badenian samples and show much longer stratigraphic ranges than known from literature data. The depositional gap at the Karpatian-Badenian boundary has a minimum duration of 0.41 My in the Krems Embayment. The combination of bio- and lithostratigraphic data allows the correlation across major faults. The Diendorf-Boskovice Fault System played an important role during basin formation and was identified as very active during the early to middle Badenian Stage. The results of this study show the complex interaction of sedimentation, tectonic activity and paleobiological developments in this peripheral part of a marginal sea.

The Śnieżka peatland as a candidate Global boundary Stratotype Section and Point for the Anthropocene series

The subalpine, atmospherically fed Śnieżka peatland, located in the Polish part of the Sudetes, is one of the nominated candidates for the GSSP of the Anthropocene. Data from two profiles, Sn1 (2012) and Sn0 (2020), from this site are critical for distinguishing the proposed epoch, while an additional core Sn2 is presented to support main evidence. The Sn0 archive contains a wide array of critical markers such as plutonium (Pu), radiocarbon (F14C), fly ash particles, Hg and stable C and N isotopes which are consistent with the previously well documented 210Pb/14C dated Sn1 profile, which provides a high-resolution and comprehensive database of trace elements and rare earth elements (REE), Pb isotopes, Pu, Cs, pollen and testate amoebae. The 1952 worldwide appearance of Pu, owing to its global synchronicity and repeatability between the cores, is proposed here as a primary marker of the Anthropocene, supported by the prominent upturn of selected chemostratigraphic and biostratigraphic indicators as well as the appearance of technofossils and artificial radionuclides.

A Glyptagnostus reticulatus trilobite faunule from the Cambrian of the Northern Qilian Mountains, northwest China, and its paleogeographical implications

AbstractA Glyptagnostus reticulatus (Angelin, 1851)–bearing trilobite assemblage has been found from an unnamed Cambrian formation in the Northern Qilian Mountains area, of which geographical placement in the Cambrian is contested. Glyptagnostus reticulatus is a biostratigraphic indicator of the Furongian Series and Paibian Stage, and three agnostoid and six polymerid taxa from the Changgou section, Daliang area are described herein, along with conspecific forms from the nearby Chuancigou section. This well-preserved assemblage shows strong taxonomic affinity with northwestern Queensland, Australia, and western Hunan–eastern Guizhou, China, and likely comes from deep outer-shelf to slope setting associated with the Northern Qilian arc. It is consistent with other arguments that during the Cambrian, the Northern Qilian arc, along with the Hexi Corridor of the Alxa terrane, were more closely allied to South China than to North China.

Geochronological aspects of terminal Late Fort Ancient sites in the Little Miami-Ohio Rivers confluence area and their archeological significance

A geochronological approach is used to examine the temporal and spatial parameters of terminal Late Fort Ancient (∼1450 –1750 CE) habitation sites in the Little Miami-Ohio Rivers confluence area. We use a Bayesian analysis of radiocarbon dates, microtephrochronology, a biostratigraphic indicator ( Bison bison), and ethnohistorical records to examine terminal Late Fort Ancient sites in this region. Circular, stockaded villages (≤ 5 ha), consisting of single-family dwellings were replaced with large linear villages (≤ 8 ha), consisting of multifamily longhouses constructed parallel to the Little Miami and Ohio rivers. Smaller contemporary habitations and a plethora of underground maize silos suggest a seasonal pattern of population fission and fusion. At the time of Hernando de Soto's military conquests, ∼350 km to the south, terminal Late Fort Ancient villages in this region were increasing in number and size.

Carboniferous crinoids

Abstract During the Carboniferous, crinoids were commonly so abundant that their skeletal ossicles formed limestones termed encrinites. Major evolutionary changes occurred within the Camerata and Articuliformes, as the former were displaced by the latter as the dominant clade. Both the Mississippian and the Pennsylvanian subperiods started with high evolutionary rates and ended with low evolutionary rates associated with glaciation. Although not typically used for biostratigraphy, crown-based crinoid genera can be used as biostratigraphic indicators for Carboniferous stages. Paleozoic crinoid biodiversity reached its maximum during the Carboniferous, from which there are numerous well-documented localities with high biodiversity. Faunas from the palaeobiogeographical regions of Laurussia, Palaeo-Tethys and Gondwana are reviewed. For Mississippian crinoids, 37 genera are designated as biostratigraphically useful; and, for the Pennsylvanian, 44 genera are identified. Recognition of the utility of these genera for biostratigraphy is important for dating crinoid deposits, which may be devoid of other biostratigraphically useful fossils, and add to our overall ability to delineate the temporal resolution of life on Earth.

Utilization of Ostracods (Crustacea) as Bioindicator for Environmental Pollutants

Ecosystem undergoes drastic changes due to the anthropogenic activities. As a consequence of industrial development, increasing population growth and modernized agricultural practices water resources like limnetic zone and marine areas have undergone eutrophication. This resulted in the decline in population of phytoplankton and zooplankton. Hence, it is an urgent need to monitor the quality of the environment. Several organisms are used as biomonitors. Among them, Ostracodes (Seed Shrimps) which belong to Crustacean group are very sensitive to those changes in the environment and useful in predicting the paleo environmental conditions. Ostracodes are bivalve arthropods which are enclosed in a carapace made of low magnesium calcite. These species are occurring for about 450 million years dates back to ordovician which are known for their easier fossilization. The development of Ostracodes is influenced by the physic - chemical properties of waters such as Salinity, temperature, pH, Dissolved oxygen, bottom grain sizes and sedimentation rates. In addition to diversity and abundance of population, morphological and geochemical changes can also be detected in the Ostracod carapace (shell) which serves as a tracer of the water quality. These details are basis for utilizing Ostracods as paleoenvironmental (paleoclimatic, paleosalinity, paleooceanographic) reconstruction, ecotoxicity monitoring, biostratigraphic indicator. Moreover, these microcrustaceans showed similar or higher sensitivity to herbicides, pesticides, oil spills or heavy metals pollution other than traditional groups like copepods, protozoan, rotifers, cladocerans which are used to test the human impacts on ecosystem. These meiofaunas are highly adaptable to waters containing organic and inorganic contaminants generated by catastrophic activities by human beings in the surroundings.

Climate variability in early expansions of Homo sapiens in light of the new record of micromammals in Misliya Cave, Israel

In this study, we provide the first taphonomic and taxonomic descriptions of the micromammals from Misliya Cave, where recently a Homo sapiens hemimaxilla has been reported. This finding significantly extends the time frame for the out-of-Africa presence of anatomically modern humans. It also provides an opportunity to reassess variation in early modern human population responses to climate change in the Levantine sequence. Information on species ranking and diversity estimations (Shannon functions) is obtained from quantitative data across 31 Levantine assemblages and investigated in a broad comparative frame using multivariate analyses. Recent models of human-climate interactions in the late Early–Middle Paleolithic of the southern Levant have drawn heavily on on-site associations of human fossils with remains of micromammals. However, there has been little, if any, attempt to examine the long-term picture of how paleocommunities of micromammals responded qualitatively and quantitatively to climatic oscillations of the region by altering their compositional complexity. Consequently, our understanding is vastly limited in regard to the paleoecosystem functions that linked past precipitation shifts to changes in primary producers and consumers or as to the background climatic conditions that allowed for the development of highly nonanalog ancient communities in the region. Although previous studies argued for a correspondence between alternations in H. sapiens and Neanderthal occupations of the Levant and faunal shifts in key biostratigraphic indicator taxa (such as Euro-Siberian Ellobius versus Saharo-Arabian Mastomys and Arvicanthis), our data indicate the likelihood that early H. sapiens populations (Misliya and Qafzeh hominins) persisted through high amplitudes of paleoecological and climatic oscillations. It is unlikely, given these results, that climate functioned as a significant filter of early modern human persistence and genetic interactions with Neanderthals in the Levant.

Marine diatoms as a stratigraphic indicator for Quaternary sediments : Focusing on the potential biostratigraphic indicator for coastal shallow marine deposits

Marine diatoms as a stratigraphic indicator for Quaternary sediments : Focusing on the potential biostratigraphic indicator for coastal shallow marine deposits

A Neognathodus-based biozonation of the Desmoinesian Series (Pennsylvanian) in the Illinois Basin, USA

AbstractThe Neognathodus Index (NI) is developed as a primary biostratigraphic indicator for the Desmoinesian Series of the Illinois Basin in Indiana, Illinois, and Kentucky. It is based on the gradual evolutionary morphotypic variations of P1 elements of named species of Neognathodus Dunn, 1970. The NI analyses and zonations presented herein are constructed from 472 productive conodont samples from 105 different localities. NIs for the Illinois Basin show morphologic drift in Indiana from the Perth Limestone Member of the Staunton Formation (NI = 2.03) to the Velpen Limestone and Mecca Quarry Shale members of the Linton Formation (NI = 5.04) followed by stability through the Alum Cave (NI = 4.83). Further morphologic drift then occurred through the Providence Limestone Member of the Dugger Formation (NI = 5.43) and continued through the West Franklin Limestone Member of the Shelburn Formation (NI = 6.32) until the extinction of Neognathodus at the end of Desmoinesian. The patterns of drift and stability translate to Neognathodus biozones and are supported by Kolmogorov-Smirnov tests of standardized Neognathodus morphotype distributions. Localized NI variations are due to morphologic shifts and differential evolution in response to localized environmental conditions. Examination of the NI differences in the states of Illinois, Kentucky, and Indiana reflect similar morphologic simplification of the P1 element from Perth to Velpen and Mecca Quarry in Indiana (NI = 2.03–5.04) and from Seville to Brereton in Illinois and Kentucky (NI = 2.80–5.00). Post-Brereton in Illinois and Kentucky (NI = 5.00–5.65) and post-Providence in Indiana (NI = 5.43–6.32) saw progressive P1 simplification, but it was much more pronounced in Indiana.

Stratigraphic distribution and biostratigraphic utility of the fossil diatom Lancineis rectilatus in the central Kanto Plain, central Japan

The stratigraphic range of extinct shallow-marine diatom species Lancineis rectilatus Naya was investigated in upper Pliocene to Holocene marine strata from five sediment cores drilled on the central Kanto Plain, central Japan. The lowest occurrence of L. rectilatus in the five cores was in the marine strata between the Kd25 and Kd12-Type tephra layers, and was dated at ca 1.45 Ma. The uppermost occurrence of L. rectilatus was in marine strata deposited during marine isotope stage 17, which has an estimated age of ca 0.7 Ma. Occurrences of L. rectilatus can thus provide a useful biostratigraphic index for sediments deposited during ca 1.45–0.7 Ma in the Kanto Plain. This is the first report showing that diatom fossil is applicable as a biostratigraphic indicator for the Quaternary shallow marine strata.

Large rotaliid foraminifera as biostratigraphic and palaeoenvironmental indicators in northwest Borneo: An example from a late Miocene section in Brunei Darussalam

Palaeonvironmental interpretations and biostratigraphic zonations in northwest Borneo are still a matter of debate but are important for petroleum related applications. The outcrop of Ambug Hill, a late Miocene marine siliciclastic sequence in Brunei Darussalam, has been investigated for its foraminifera assemblage. From a 9.5 m clay-rich interval 50 taxa have been recognized and classified, whenever possible to species level. The studied fauna is characterized by mostly hyaline foraminifera, dominated by two rotaliid species: Cavarotalia annectens and Heterolepa dutemplei. Additionally, a number of miliolids, lageniids, bolivinids and also planktonic foraminifera are present but in much lower abundance. The dominance of the rotaliids points to a sea floor rich in organic carbon characterized by muddy substrates with very low light penetration and the possible growth of patchy sea grass or macroalgae in the system, as indicated by epiphytic foraminifera in the samples. The results obtained give additional insights on how the environmental conditions might have been during the deposition of the deltaic sequences very widespread in the region, and how the fauna coped with such settings. Throughout the investigated samples, the dominance of the assemblages clearly shows alternating stress conditions, typical of pro- deltaic environments.The large abundance of rotaliid foraminifera, points toward possible biostratigraphic applications as several taxa within this group have short biozones in the region even though have strong facies dependency. If their role as biostratigraphic indicators could be finally proven, they might be used to date the large depositional sequences occurring in the region, since planktonic index fossils are scarce due to the very proximal settings of the sediments.

The Bartonian unit stratotype (S. England): Assessment of its correlation problems and potential

The problems of correlation of strata belonging to the unit Bartonian Stage in its type area of the Hampshire Basin, UK, are reviewed. These problems involve not only correlation outside the Hampshire Basin, through biostratigraphy and magnetostratigraphy, but also within the basin in terms of understanding patterns of facies distributions and reliability of local biostratigraphy. On the basis of a combination of calcareous nannoplankton, dinoflagellate cyst and magnetostratigraphic evidence, the base of the type unit Bartonian lies within Chron C18r. However, no reliable biostratigraphic indicators have yet been found to allow a more precise correlation of the base. It is suggested that more detailed microfossil and palaeomagnetic sampling at key sites could resolve these problems in order to help further the quest for an appropriate Global Stratotype Section and Point (GSSP) for the Bartonian Stage.

The rodent succession in the Sifón de Librilla section (Fortuna Basin, SE Spain): implications for the Mio-Pliocene boundary in the Mediterranean terrestrial record

The long and continuous continental section of Sifón de Librilla (Fortuna Basin, southern Spain) provides a detailed biostratigraphic record distributed along eight localities, in which the magnetostratigraphy has been unambiguously established. This section therefore provides a unique opportunity to cross biostratigraphic information with magnetostratigraphic data to establish a reliable frame to date sites. This 800-m-thick sequence extends from the latest Miocene to the early Pliocene, recording more than 2 Myr. Here we provide a complete taxonomic survey of the recovered rodent remains, defining a new cricetid species named as Hispanomys romeroi. We also refine the phylogenetic relationships of the Apodemus, Stephanomys, Paraethomys, Ruscinomys and Apocricetus lineages. Considering the accurate age of the associations, we discuss the chronology of the first and last appearances of some species. In addition, this section clearly records the Mio-Pliocene boundary, allowing us to correlate between the marine and continental biostratigraphic scales. Taking advantage of this opportunity, we explore key biostratigraphic indicators for identifying the beginning of the Pliocene in the continental records, as well as for differentiating the MN13 and MN14 units, most specially the FOD of Occitanomys brailloni. According to this datum, we conclude that the Miocene-Pliocene boundary coincides with that of MN13-MN14 units. http://www.zoobank.org/urn:lsid:zoobank.org:act:BDA60E97-C23B-482D-AD0D-9C25FDF5FA05

Un nuevo Notungulado Hipsodonte (Hegetotheriidae, Pachyrukhinae) del Mioceno tardío de la Cordillera Oriental, provincia de Salta, Noroeste de Argentina.

Late Miocene fluvial strata of the Palo Pintado Formation are broadly exposed to the northwest of the town of Angastaco, Salta province, Northwest of Argentina. These strata accumulated in the extensional Angastaco Basin. Recent field work at the Palo Pintado Formation (late Miocene), Valle Calchaqui, Salta province, Argentina has provided fossil remains that greatly increased the knowledge of the faunal assemblage of this site. A number of notoungulates and rodents were collected. A partial left jaw was collected at Quebrada Penas Blancas along the west bank of the Rio Calchaqui. Morphological and morphometric comparisons permit referral of this specimen to a new species of hegetotheriid notoungulate Paedotherium kakai sp. nov. It represents the first report of Paedotherium for the Eastern Cordillera and one of the few well-documented occurrences of this genus outside of middle-high latitudes Argentina. The widespread geographic range of Paedotherium, combined with its restricted temporal range, suggest it may be one of the most useful biostratigraphic indicator taxa for Neogene faunas. Paedotherium kakai would have been a mixed feeder that lived in gallery forests, feeding close to water bodies of a system river and lagoons, in food plains developed under humid and subtropical climate.

Cricetodontini from the Calatayud–Daroca Basin (Spain): A taxonomical description and update of their stratigraphical distributions

The most updated stratigraphical distributions of the Cricetodontini from the Calatayud–Daroca Basin are presented. Cricetodon sansaniensis (local biozone F, MN6, middle Aragonian) and Cricetodon jotae (local biozone G1, G2 and G3, MN6-MN7/8, Middle–Upper Aragonian) from the middle Miocene are described and discussed. Generally, the genera of Cricetodontini were used to define large time intervals, whereas the species were neglected in the local biostratigraphical studies. The results presented herein show that, for the Calatayud–Daroca Basin, most of the stratigraphical distributions of the species of Cricetodontini are strongly linked with the local biozonation. That reveals that they could be used as good biostratigraphical indicators. Moreover, the unusually long local biozone G3 could be redefined and subdivided based on the distributions of the four species of Cricetodontini present in it. However, it is recommended to complete the study of the whole rodent fauna before proposing a new biozonation.

Environmental changes of the Mazovian (Holsteinian /~MIS 11) palaeolake near Szymanowo (eastern Poland) in the light of malacological analysis

Abstract The malacofauna of the palaeolake deposits at Szymanowo (eastern Poland) was investigated. It represents the younger part of the climatic optimum of the Mazovian (Holsteinian) Interglacial (~MIS 11) and possibly the postoptimal period. The mollusc assemblage is composed of both standing and running water species, mostly connected with temperate climate. The presence of biostratigraphical indicators of the Mazovian, Viviparus diluvianus (Kunth, 1865), Lithoglyphus jahni Urbański, 1975 and Pisidium clessini Neumayr, 1875, is noteworthy. Variability in the structure and composition of the assemblage enables palaeoecological reconstruction. Changes in the water-level, vegetation and energy conditions are inferred from the malacological succession. Three stages of the lake development were distinguished. The first one is connected with deeper conditions and predominance of V. diluvianus and L. jahni. The second one, dominated by Bithynia tentaculata (Linnaeus, 1758), records a fall of the water-level and the growth of aquatic plants, evidenced by high frequencies of Valvata cristata Muller, 1774 and Acroloxus lacustris (Linnaeus, 1758). The third stage corresponds to another rise of the water-level and an increase in V. diluvianus, L. jahni, Valvata piscinalis Muller, 1774 and Pisidium henslowanum (Sheppard, 1823), which evidence some higher energy conditions.