Search results for " Ostra"
showing 10 items of 19 documents
Karyotype variability and inter-population genomic differences in freshwater ostracods (Crustacea) showing geographical parthenogenesis
2018
Transitions from sexual to asexual reproduction are often associated with polyploidy and increased chromosomal plasticity in asexuals. We investigated chromosomes in the freshwater ostracod species Eucypris virens (Jurine, 1820), where sexual, asexual and mixed populations can be found. Our initial karyotyping of multiple populations from Europe and North Africa, both sexual and asexual, revealed a striking variability in chromosome numbers. This would suggest that chromosomal changes are likely to be accelerated in asexuals because the constraints of meiosis are removed. Hence, we employed comparative genomic hybridization (CGH) within and among sexual and asexual populations to get insigh…
Un capitello tardoantico frammentario dallo scavo di Ostra
2020
Analisi di un capitello lapideo frammentario, di epoca tardoantica, rinvenuto nel corso delle moderne ricerche archeologiche nella città romana di Ostra nelle Marche
Generic revision of Cypricercinae McKenzie, 1971 (Crustacea, Ostracoda), with the description of three new genera and one new species and a phylogene…
2009
The Cypricercinae are one of the most speciose subfamilies of non-marine ostracods, with more than 170 described species, mostly from the tropics. Although the identity of the subfamily as such is clear, because of the presence of unifying characters such as the Triebel’s loop in the attachment of the caudal ramus, the supra-specific taxonomy of this group has long been confused because of lack of good generic and tribal characters. Here, the generic characters of the Cypricercinae are revised. Eleven genera are retained in this subfamily, including three new genera: Bradleytriebella n. gen., Nealecypris n. gen. and Pseudostrandesia n. gen. Tanycypris siamensis n. sp. is described from Thai…
Depositional environment and biofacies characterisation of the Triassic (Carnian to Rhaetian) carbonate succession of Punta Bassano (Marettimo Island…
2007
AThe aims of this study are to reconstruct the geological setting of the Punta Bassano series (Marettimo Island, Egadi Archipelago, western Sicily) and its palaeogeographic evolution. The reference section for the Upper Triassic of Marettimo shows an alternation of marl and limestone beds together with brecciated levels. The limestones are both homogeneous mudstones with evaporite pseudomorphs and laminated with fenestrae. Foraminiferal, palynomorph, and ostracod associations constrain the Punta Bassano sequence to the Carnian-Rhaetian interval. The Punta Bassano succession represents a shallow inner ramp, ranging from open-marine environment with good water circulation to lagoonal and peri…
Alena, garsa de mar, Ostrero euroasiático (VER0000098)
Altres noms vulgars: Eurasian Oystercatcher (Anglès), Huîtrier pie (Francès), Austernfischer (Alemany) Gabinet de Vertebrats (Departament de Zoologia), Facultat de Ciències Biològiques (Campus de Burjassot), C/ Doctor Moliner, s/n, Bloque B. 5é plant, Burjassot (Valencia). Armari: 10-1 Adulto
LOCHKOVIAN TO PRAGIAN (LOWER DEVONIAN) NERITIC OSTRACODES FROM NIGÜELLA (ZARAGOZA, IBERIAN CHAINS, NE SPAIN)
2021
Lochkovian and Pragian ostracodes from the area of Niguella (Iberian Chains), which is a key area for supra-regional correlation in the Early Devonian, are described for the first time. 12 ostracode taxa from the sections Ni4 and Ni2 could be identified. The silicified ostracodes of Eifelian Ecotype are low in biodiversity, have few individuals, and are comparatively poorly preserved. Characteristic taxa of the Devonian occur. Thus, the faunas show general relations to most European Early Devonian ostracode faunas. Closer relations exist to the Eastern Guadarrama. Polyzygia kroemmelbeini LeFevre & Weyant, 1967 and P. grekoffi Weyant, 1980 are found in the basal Pragian for the first time. B…
The late Messinian "Lago-Mare" event and the Zanclean Reflooding in the Mediterranean Sea: New insights from the Cuevas del Almanzora section (Vera B…
2020
Abstract The return to normal marine conditions in the Mediterranean Sea after the end of the Messinian Salinity Crisis (MSC), that led to the deposition of thick evaporitic succession followed by settlement of brackish to freshwater conditions of the “Lago-Mare”, is still subject to extensive debate between two opposite scenarios. One scenario implies an abrupt reflooding through the Gibraltar gateway of the Mediterranean Sea previously disconnected from the world ocean and partly desiccated. The second scenario postulates that the Mediterranean Sea kept a high-water level throughout the Messinian Salinity Crisis and was connected continuously to the Atlantic Ocean and to the Paratethys. T…
PALEOENVIRONMENTAL RECONSTRUCTION ON LATE CALABRIAN STAGE SEDIMENTS FROM THE BELICE VALLEY (SOUTHWESTERN SICILY - ITALY) BASED ON OSTRACODA
2022
The Middle Pleistocene Transition is the most recent re-organization of the climate system, happened between 1.2 and 0.7 Ma. Marine sediments outcropping in Sicily have been a relevant source of information on the paleoclimatic and paleoenvironmental evolution of the Mediterranean Sea, over this time window. Among others, previous studies in Sicily identified and described the very cold phase and the marked sea level fall associated with the top MIS 22, which is lithologically expressed by a calcarenite bed colonized by the Arctica islandica northern guest. Here we investigate ostracod assemblages from marine sediments in the southwestern Sicily. Sediments, ascribed to the late Calabrian St…
The microcrustacean fauna of Sicily and the Central Mediterranean Sea area - Current knowledge and gaps to be filled
2006
The current knowledge of freshwater entomostracans from Sicily and some neighbouring central-Mediterranean countries is briefly reviewed. Data concerning different countries and different taxonomical groups are markedly inhomogeneous and often far from being representative of the real biota of the corresponding countries. This gap prevents a sound biogeographical analysis of the freshwater microcrustacean fauna of the area. The major gaps that have to be filled are highlighted and the need for more surveys and monitoring is emphasised.