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Taxonomic harmonization of Neogene and Quaternary candonid genera (Crustacea, Ostracoda) of the Paratethys
No full textDuring 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. http://zoobank.org/urn:lsid:zoobank.org:pub:EB9EC2D4-AFD2-428E-9958-C97F36ED7FF2
An Early Jurassic oligohaline ostracod assemblage within the marine carbonate platform sequence of the Venetian Prealps, NE Italy
No full textMicropalaeontological investigation of one of a number of black shale horizons within the carbonate platform sediments of
the Calcari Grigi Formation (Trento Platform, NE Italy) has yielded the ®rst recorded oligohaline, early Jurassic, ostracod
assemblage. The shale is dated as late Sinemurian on the basis of large benthic foraminiferal biostratigraphy in the sediments
above and below. The shale is devoid of foraminifera and ammonites, which supports a non-marine context. Three previously
unknown ostracod species are identi®ed, however, the assemblage is dominated (.95%) by a single taxon which is erected as a
new genus and species (Phraterfabanella tridentinensis Whatley and Boomer gen. et sp. nov.) which further supports the
interpretation of a astressedo environment. The two remaining ostracod taxa are assigned to Klieana and Limnocythere both
considered to represent non-marine or very low salinity conditions. This new genus includes probable members from the Rhaetian
of Hungary and France as well as from the Liassic of France. The new genus is shown to be one of the earliest representatives of the
Cytherideidae, a family which survives to the present and includes the modern pandemic, euryhaline species Cyprideis torosa.
The discovery of such an assemblage within an otherwise marine sequence indicates temporary, physical isolation from
marine in ̄uence. Sedimentological, faunal and geochemical evidence suggests that the organic rich shale may indicate high
organic carbon supply via continental runoff in this tropical palaeogeographical setting. Resulting dysaerobia within the
sediment would have created a particularly stressed environment
Ostracod-bivalve response to shallow water poikiloaerobic conditions: Lower Jurassic black-shales (Veneto, northern Italy).
No full textMicro- and macrofossils as palaeoenvironmental proxies in Liassic oligohaline ecosystem (Trento Platform, north-eastern Italy).
No full textJurassic ostracod
Faunal assemblages and palaeoenvironment of shallow water black shales in the Tonezza area (Calcari Grigi, Early Jurassic, Southern Alps).
No full textLower Jurassic shallow water carbonate successions from the Tonezza area (Vicenza, northeastern area) were analysed in terms of lithology, biotic components, facies. In these successions black shales horizon occur. These are characterised by high organic contetn and by a unique bivalve and ostracod fauna. The facies analysis and the palaeoecological analysis suggest a oligohaline, non-marine laggonal settings for these benthic communities
Associazioni faunistiche e paleoambiente di black shales d'acqua bassa nei Calcari Grigi (Piattaforma di Trento, Giurassico inferiore)
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Associazioni faunistiche e paleoambiente di black shales d’acqua bassa nei Calcari Grigi (Piattaforma di Trento, Giurassico inferiore.
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