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During the Cenozoic, the constant northward movement of the African plate led to the division of the Tethys Ocean into two: the Palaeomediterranean and the Paratethyan branches. The latter was represented by a huge epicontinental sea and brackish to freshwater lakes that extended across central Europe and western Asia. Neogene and Quaternary ostracods from the Paratethys originated through major adaptive radiations, which gave rise to endemic brackish taxa. Unfortunately, much confusion surrounds their taxonomy, due to the quality of descriptions and images in the original literature and the incompleteness of the type material, making necessary a taxonomic revision. In this paper, we propose a systematic revision of several Paratethyan endemic candonid genera based on the analysis of the type material, new material collected from the type localities, and new fossil material from the Ponto-Caspian area. The study focuses on the description of the valve morphology and particularly on the geometric morphometric analysis of the valve outline. Thirty-three genera were taken into account of which four (Advenocypris, Candoniella, Graviacypris, Telekia) were considered to be junior synonyms of Typhlocypris, Pseudocandona or Candona. Moesiella is considered a nomen nudum. In the case of Caspiollina, Dacicandona, Liventalina and Turkmenella the scarcity of material and/or the poor descriptions reported in the literature prevented us from performing a full revision. The monospecific genus Thaminocypris possibly includes a teratological form. The remaining 23 genera were merged into nine valid, endemic, genera (Bakunella, Camptocypria, Caspiocypris, Hastacandona, Lineocypris, Pontoniella, Propontoniella, Typhlocyprella and Zalanyiella). Emended diagnoses and descriptions are proposed for these genera and a new species, Bakunella anae sp. nov., is described. This study considerably reduces the taxonomic uncertainty within the Paratethyan candonids, providing new data for the evaluation of the palaeobiodiversity of the Paratethyan domain. Finally, the palaeobiogeography of Paratethyan candonids during the Neogene and Quaternary is also discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper the ostracod assemblages recovered from several brackish Late Miocene Italian deposits have been analysed from a palaeobiogeographical perspective. During late Tortonian-early Messinian it is possible to recognize in Italy rich ostracod assemblages characterized by a wide contingent of taxa with central European or Mediterranean affinity, while only few brackish and freshwater ostracods show Paratethyan affinity. The recognized composition of the ostracod assemblages matches the palaeogeographic setting of the palaeo-Mediterranean/Paratethys at that moment. In fact during late Tortonian-early Messinian the palaeo-Mediterranean and Paratethysian domains were divided and, even if the connection via the present Marmara Sea-Strimon Basin was still open, the different salinity between them represented an ecological barrier, preventing faunal exchanges. Since normal aquatic migration was impossible, it must be assumed that the Paratethyan-like taxa entered the palaeo-Mediterranean area via passive dispersal by aquatic birds. On the contrary, the ostracod assemblages from the Italian Lago-Mare deposits show the absolute predominance of Paratethyan taxa, which, according to the known palaeogeographic setting during the late Messinian Lago-Mare event, could actively migrate from the Paratethys domain, colonizing the palaeo-Mediterranean, whose endemic fauna was severely impoverished by the Messinian salinity crisis and the following water dilution. [Copyright &y& Elsevier]

Abstract: In the Crete Island, late Messinian Lago-Mare facies are not well known. At present, the occurrence in Crete of the uppermost Messinian post evaporitic deposits is a matter of debate. According to several authors, the well-known late Messinian Lago-Mare facies does not occur in Crete. In this paper the preliminary results obtained from the biostratigraphical analysis of some sections sampled in the Messarà Plain will be shown. Nearby Faneromeni and Ano Akria villages, the Miocene/Pliocene boundary is well exposed. There, gypsum-bearing clay, laminated microcrystalline gypsum and gypsum-rudites characterize the evaporitic deposits of the Messinian stage. In these areas, above the Messinian evaporite, post-evaporitic fine-laminated polychrome clays, with intercalations of sandstones and conglomerates, have been found. In both the Faneromeni and Ano Akria area, the Pliocene grey clays and conglomerates rest unconformably on the uppermost Messinian post-evaporitic deposits. A 20cm-spaced sampling has been performed in both the sections, for more than 100 samples collected. The results of the micropaleontological analysis performed on the Faneromeni and Ano Akria sections point to the occurrence of ostracod assemblages containing: Loxocauda limata (Schneider in Agalarova et al.), Loxocauda sp., Cytherura pyrama Schneider, Cyprideis anlavauxensis Carbonnel, Cyprideis agrigentina Decima, Amnicythere palimpsesta (Livental), Amnicythere propinqua (Livental), Amnicythere accicularia (Olteanu), Amnicythere costata (Olteanu), Amnicythere multituberculata (Livental), Amnicythere sp. D (Miculan in Bassetti et al.), Amnicythere sp. 2 Gliozzi and Grossi, Amnicythere sp., Euxinocythere (Maeotocythere) praebaquana (Livental in Agalarova et al.), Mediocytherideini indet., Pontoniella pontica (Agalarova), Camptocypria sp. 1 Gliozzi and Grossi, Caspiocypris sp., Zalanyiella venusta (Zalanyi), Tyrrhenocythere sp., Loxoconcha rhombovalis Pokorny, Loxoconcha eichwaldi Livental, Loxoconcha sp. A (Miculan in Bassetti et al.), Loxocorniculina djafarovi (Schneider in Suzin). In the analysed samples, reworked planktonic foraminifers and well-preserved charophyte gyrogonites have been also found. The ostracod assemblages found in the Messarà Plain belong to the Loxocorniculina djafarovi Zone (sensu Carbonnel, 1978), which characterizes the uppermost Messinian deposits of the whole Mediterranean Basin. At that time, the well-known Lago-Mare biofacies was also widespread on the Crete Island. The presence of Paratethyan ostracods in the post-evaporitic Messinian deposits of both Faneromeni and Ano Akria sections suggests that in the Crete Island the latest Messinian sedimentation took place in brackish water palaeoenvironments. [Copyright &y& Elsevier]

Abstract: The Late Miocene Italian brackish Loxoconchidae are herein discussed and illustrated. Three genera and two subgenera have been recognized in the brackish Italian basins: Loxoconcha, Loxocorniculina, Loxoconchissa (Loxoconchissa) and Loxoconchissa (Loxocaspia). Taking into account the diagnostic characters of several Loxoconchidae genera, in this paper Loxocorniculina is raised at a generic rank, Loxocaspia is confirmed as a subgenus within genus Loxoconchissa and several new species are established: Loxoconchissa (Loxoconchissa) kinoi nov. sp., Loxoconchissa (Loxocaspia) cosentinoi nov. sp., Loxoconchissa (Loxocaspia) nuda nov. sp., Loxoconchissa (Loxocaspia) punctata nov. sp., Loxoconchissa (Loxocaspia) reticulata nov. sp., Loxoconchissa (Loxocaspia) tuberosa nov. sp. and Loxoconchissa (Loxocaspia) velonae nov. sp. Loxocorniculina is a typical Paratethyan genus which widespread into the Palaeo-Mediterranean during the late Messinian Lago-Mare event. Loxoconchissa was known to be widespread only in the Paratethyan realm and in this paper it is signalled for the first time in the Late Tortonian-early Messinian of Italy. The palaeobiogeography of these genera is discussed and the observed continuous distribution of Loxocorniculina against the disjunct distribution of Loxoconchissa leads to suggest that this latter genus underwent a passive dispersal via aquatic birds. [Copyright &y& Elsevier]