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Reggio nell'Emilia, Italy

Caucia F.,University of Pavia | Marinoni L.,University of Pavia | Callegari A.M.,University of Pavia | Leone A.,University of Pavia | Scacchetti M.,Societa Reggiana di Science Naturali
Neues Jahrbuch fur Mineralogie, Abhandlungen | Year: 2016

Crystals of the beryl variety morganite, hosted in a pegmatitic dike of the Island of Elba were analyzed by standard gemological methods, LA-ICP-MS, single crystal XRD and spectroscopic methods. The samples show a stubby and tabular shape, appear transparent, pastel colored and light in tone with different shades of color: very light pink, light pink, pink. The structure refinement showed a reduced replacement in the octahedral and in the T2 tet-rahedral sites. The most abundant elements are Al (around 7 %) and Be (around 5 %), followed by the alkali and earth alkali metals Cs (around 5100 ppm), Na (around 2700 ppm), Ca (1600 ppm), Li (around 1400 ppm), Rb (240 ppm) and K (150 ppm). The total of alkali metals is around 1.1 %, so that morganites plot in class 5 of the classification by Cerny (1975). Cs generates the UV luminescence. Alkali elements are interpreted as hosted into the structural channels of the mineral. Mn is the most important chromophore element and responsible for the pink color. The high contents of earth alkali and alkali metals indicate that morganite formed during the late stage of pegmatitic evolution with a possible influence of carbonate country rocks. © 2015 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.

Borghi E.,Societa Reggiana di Science Naturali | Garilli V.,Research and Educational Service
Journal of Systematic Palaeontology | Year: 2016

The regular echinoid Placentinechinus davolii gen. et sp. nov. is described from eight Early Pleistocene (Gelasian–Calabrian) sites in north and south Italy. It is the most recent record known for the family Temnopleuridae in the European domain and the first in the Mediterranean area. A review of temnopleurid palaeobiogeography, and morphological comparisons, suggest that P. davolii was derived from a marsupiate brooder that lived in the north-east Atlantic during Messinian–middle Gelasian time. This indicates a brooding reproductive strategy for P. davolii, although it does not bear any evidence of a marsupium. The stratigraphy and climatic setting inferred for the study sites indicate that Placentinechinus represents a significant southward shift of the European Temnopleuridae, triggered by a progressive cooling that changed the Mediterranean climate from tropical to subtropical-temperate. A further climatic deterioration, perhaps that at about 0.8 Ma with the onset of the 100 kyr-controlled Ice Ages, caused its extinction. The palaeoecology of Placentinechinus, as deduced from palaeoenvironmental reconstructions of the study sites, indicates that it lived in shoreface to shallow offshore, moderately agitated waters, often together with the scallop-polychaete Aequipecten-Ditrupa association. It tolerated more or less marked conditions of turbidity, but flourished in trophically well-structured palaeocommunities. The main morphological characters distinguishing Placentinechinus are the very depressed test and the extremely large apical opening, up to 82% of the test diameter, which is so far the largest known for an adult echinacean echinoid. The statistically exhaustive morphometric data collected from more than 100 Placentinechinus tests indicate that inferring sexual dimorphism for Temnopleuridea echinoids based only on the apical disc width could be misleading. For P. davolii, both climate and environmental stability, in terms of sedimentation rate and nutrient supply, may have been concurrent drivers of its evolutionary history. http://zoobank.org/urn:lsid:zoobank.org:pub:EBB96C8C-943D-4253-82FE-09B9132591E7 © The Trustees of the Natural History Museum, London 2016. All Rights Reserved.

Stara P.,Museo di Storia Naturale Aquilegia | Borghi E.,Societa Reggiana di Science Naturali
Bollettino della Societa Paleontologica Italiana | Year: 2012

A new species of the genus Faorina Gray, 1851 (Echinoidea, Pericosmidae) from the early Miocene of Sardinia, F. maullui sp. nov., is described. This is the first fossil evidence of Faorina and the first record from the Mediterranean area. The new species differs from the Recent F. chinensis Gray, 1851, so far considered to be the only valid species of the genus, in having a depressed test, with oblique posterior face and thinner margin, a different pathway of the peripetalous fasciole and larger periproct. The diagnostic characters stated in the literature to distinguish Faorina are discussed on the basis of the new material under study, and the meridoplacous structure in the interambulacrum 1 adorally is herein considered to be the only safe feature to distinguish Faorina from the closely related genus Pericosmus L. Agassiz, in L. Agassiz & Desor, 1847. Three species from the Miocene of Italy, originally attributed in the literature to the genus Pericosmus, are transferred into Faorina.

Stara P.,Centro Studi Of Storia Naturale Del Mediterraneo Museo Of Storia Naturale Aquilegia And Geomuseo Monte Arci | Borghi E.,Societa Reggiana di Science Naturali | Kroh A.,Natural History Museum of Vienna
Bulletin of Geosciences | Year: 2016

New material from the Miocene of Italy allows revision of the spatangoid genus Mariania Airaghi, 1901 and proposal of an emended diagnosis. Particularly characteristic, previously overlooked features of the genus include the presence of well-developed phyllodes made up from short, almost equidimensional plates in oral ambulacra II, III and IV. Unlike in other Spatangoidea, where the adoral plates rapidly become elongated towards the margin, they stay short in Mariania and are not constricted halfway between the peristome and the margin. In addition, most species of Mariania possess a characteristic domal profile with steep sides and lack a raised keel in aboral interambulacrum 5. Their petals are wide, open distally and extend almost to the margin. The plastron is not indented behind the episternal plates and the labral plate extends to the second ambulacral plates. Fascioles are missing in all specimens examined. The combination of these morphological features enable the separation of Mariania from the genera Macropneustes, Hypsopatagus and Spatangus, to which members of the genus have been assigned by previous authors. Cladistic analysis carried out to unravel the uncertain systematic position of Mariania failed to find well-supported relationships, but firmly places Mariania within the Brissidina. Most previous family attributions could be, however, ruled out. Based on the available data a placement within Spatangoidea seems most likely, where it takes up an intermediate position between maretiids, loveniids and spatangids. Three different species are identified within the studied sample: Mariania marmorae, the type species of the genus; M. stefaninii sp. nov. from the late Burdigalian-early Langhian of northern Italy; M. comaschicariae sp. nov. from the Burdigalian of Sardinia. These new species are distinguished from M. marmorae by their lower tests, shorter labral plates and shorter petals. Mariania comaschicariae sp. nov. differs from M. stefaninii sp. nov. by its lower test, more anterior apical disc and less numerous plates in the oral anterior paired ambulacra. Test morphology and parent rock sedimentology suggest that Mariania was an epifaunal echinoid, which lived in inner shelf environments, characterized by soft bottoms and a tropical climate. © 2016, Czech Geological Survey. All rights reserved.

Garilli V.,APEMA Research and Educational Service | Borghi E.,Societa Reggiana di Science Naturali | Galletti L.,APEMA Research and Educational Service | Pollina F.,APEMA Research and Educational Service
Bollettino della Societa Paleontologica Italiana | Year: 2010

The first Sicilian record of the sand dollar Amphiope is reported on the basis of the occurrence of the species A. bioculata (des Moulins, 1837), recovered from a previously unreported sandy deposit cropping out near Case Genna (western Sicily). The best preserved tests are described and compared with similar congeners. Taphonomic and palaeoecological observations on the A. bioculata-thaphocenoses, and granulometric characterizations indicate that the sand dollar-bearing deposit formed in very shallow, nearshore environments subjected to bottom current. This deposit, if considered as a subunit of the deltaic upper Tortonian-lower Messinian "Molassa" of the Terravecchia Formation, would have a late Miocene age (upper Tortonian). In this case the Mediterranean distribution of A. bioculata, previously known from the Aquitanian to the lower Tortonian, should be extended to the upper part of the latter stage.

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