scholarly journals Palaemon monsdamarum n. sp. (Crustacea, Decapoda, Palaemonidae) from the late Miocene of Mondaino (Rimini, Emilia-Romagna, Italy)

2017 ◽  
Author(s):  
Giovanni Pasini ◽  
Alessandro Garassino
Keyword(s):  
Late Miocene ◽  
Fossil Record ◽  
First Report ◽  
Upper Miocene

We report Palaemon monsdamarum n. sp. (Crustacea, Decapoda, Palaemonidae) from the tripoli of the Messinian (upper Miocene) of Mondaino (Rimini, Emilia-Romagna, Italy). The presence of a new caridean species expands the scarce knowledge on the distribution and environmental range for the genus, usually scarcely reported in the worldwide Cenozoic fossil record. This is the first report of a carideans from the Miocene of Italy.

scholarly journals Palynological profile and depositional environment of the Ishim formation (upper Miocene) in Tobol-Ishim interfluve, Western Siberia

2019 ◽  
Vol 27 (6) ◽  
pp. 103-123
Author(s):  
O. B. Kuzmina ◽  
I. V. Khazina ◽  
P. V. Smirnov ◽  
A. O. Konstantinov ◽  
A. R. Agatova
Keyword(s):  
Late Pleistocene ◽  
Organic Substance ◽  
Late Miocene ◽  
Depositional Environment ◽  
Western Siberia ◽  
Ice Age ◽  
Quaternary Sediments ◽  
Upper Miocene ◽  
Neogene Sediments ◽  
First Time

For the first time some outcrops of the Upper Miocene Ishim Formation on the south of Tyumen Area near Pyatkovo, Masali and Bigila villages are studied by palynological method in detail. A series of mineralogical analyzes of these sediments and radiocarbon analysis of the Quaternary sediments overlying the Ishim Formation are done. Four palynocomplexes (PC) are established in the Ishim Formation: PC1 with Botryococcus; PC2 with Botryococcus, Sigmopollis; PC3 with Alnus, Polypodiaceae, Botryococcus, Sigmopollis; PC4 with Betula, Alnus, Corylus. The layers with PC1, PC2 и PC3 are traced in two outcrops near Masali and Bigila Villages. PC4 is revealed from the sands and aleuropelits of the outcrop near Pyatkovo Village, it is characterized by a significant content of diverse pollen of temperate termophylic broad-leafed taxa and by the presence of rare typical Miocene elements (Таxodiaceae, Nyssa, Tsuga). The PC3 and PC4 are compared with the complexes well known from the Neogene sediments of Western Siberia. PC5 with Betula, Herbae, Fungi is revealed from the bedded silts overlying the Ishim Formation in Masali outcrop. Previously, these sediments were attributed to the Late Miocene Pavlodar Formation. The composition and the structure of PC5 allowed making an assumption about Quaternary age of the enclosing sediments. Radiocarbon analysis of the organic substance from the silts showed, that these sediments were accumulated in the Late Pleistocene (Sartan Ice Age). For the first time the information about microphytoplankton (Botryococcus, Pediastrum, Zygnemataceae, Sigmopollis) and other nonpollen palynomorphs, contained in Ishim Formation (Upper Miocene) and in Pleistocene sediments, is given. On palynological data, some stages of development of the Late Miocene Ishim Basin and the type of vegetation surrounding this basin are considered. The depositional environment of Pleistocene sediments (Masali outcrop) is reconstructed.

scholarly journals Unsupervised learning of satellite images enhances discovery of late Miocene fossil sites in the Urema Rift, Gorongosa, Mozambique

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11573
Author(s):  
João d’Oliveira Coelho ◽  
Robert L. Anemone ◽  
Susana Carvalho
Keyword(s):  
Unsupervised Learning ◽  
Late Miocene ◽  
Fossil Record ◽  
Satellite Images ◽  
Near Infrared ◽  
Rift System ◽  
East African Rift System ◽  
Coastal Forests ◽  
Hominin Evolution ◽  
Fossil Site

Background Paleoanthropological research focus still devotes most resources to areas generally known to be fossil rich instead of a strategy that first maps and identifies possible fossil sites in a given region. This leads to the paradoxical task of planning paleontological campaigns without knowing the true extent and likely potential of each fossil site and, hence, how to optimize the investment of time and resources. Yet to answer key questions in hominin evolution, paleoanthropologists must engage in fieldwork that targets substantial temporal and geographical gaps in the fossil record. How can the risk of potentially unsuccessful surveys be minimized, while maximizing the potential for successful surveys? Methods Here we present a simple and effective solution for finding fossil sites based on clustering by unsupervised learning of satellite images with the k-means algorithm and pioneer its testing in the Urema Rift, the southern termination of the East African Rift System (EARS). We focus on a relatively unknown time period critical for understanding African apes and early hominin evolution, the early part of the late Miocene, in an overlooked area of southeastern Africa, in Gorongosa National Park, Mozambique. This clustering approach highlighted priority targets for prospecting that represented only 4.49% of the total area analysed. Results Applying this method, four new fossil sites were discovered in the area, and results show an 85% accuracy in a binary classification. This indicates the high potential of a remote sensing tool for exploratory paleontological surveys by enhancing the discovery of productive fossiliferous deposits. The relative importance of spectral bands for clustering was also determined using the random forest algorithm, and near-infrared was the most important variable for fossil site detection, followed by other infrared variables. Bands in the visible spectrum performed the worst and are not likely indicators of fossil sites. Discussion We show that unsupervised learning is a useful tool for locating new fossil sites in relatively unexplored regions. Additionally, it can be used to target specific gaps in the fossil record and to increase the sample of fossil sites. In Gorongosa, the discovery of the first estuarine coastal forests of the EARS fills an important paleobiogeographic gap of Africa. These new sites will be key for testing hypotheses of primate evolution in such environmental settings.

The Late Miocene-Early Pliocene out-of-sequence thrusting event: new insights into the tectonic evolution of the southern Apennines (Italy)

2021 ◽  
Author(s):  
Vitale Stefano ◽  
Prinzi Ernesto Paolo ◽  
Francesco D'Assisi Tramparulo ◽  
Sabatino Ciarcia
Keyword(s):  
Late Miocene ◽  
Hanging Wall ◽  
Early Pleistocene ◽  
Normal Faults ◽  
Southern Apennines ◽  
Campania Region ◽  
Early Pliocene ◽  
Upper Miocene ◽  
Thrust System ◽  
Tectonic Windows

<p>We present a structural study on late Miocene-early Pliocene out-of-sequence thrusts affecting the southern Apennine chain. The analyzed structures are exposed in the Campania region (southern Italy). Here, leading thrusts bound the N-NE side of the carbonate ridges that form the regional mountain backbone. In several outcrops, the Mesozoic carbonates are superposed onto the unconformable wedge-top basin deposits of the upper Miocene Castelvetere Group, providing constraints to the age of the activity of this thrusting event. We further analyzed the tectonic windows of Giffoni and Campagna, located on the rear of the leading thrust. We reconstructed the orogenic evolution of this part of the orogen. The first was related to the in-sequence thrusting with minor thrusts and folds, widespread both in the footwall and in the hanging wall. A subsequent extension has formed normal faults crosscutting the early thrusts and folds. All structures were subsequently affected by two shortening stages, which also deformed the upper Miocene wedge top basin deposits of the Castelvetere Group. We interpreted these late structures as related to an out-of-sequence thrust system defined by a main frontal E-verging thrust and lateral ramps characterized by N and S vergences. Associated with these thrusting events, LANFs were formed in the hanging wall of the major thrusts. Such out-of-sequence thrusts are observed in the whole southern Apennines and record a thrusting event that occurred in the late Messinian-early Pliocene. We related this tectonic episode to the positive inversion of inherited normal faults located in the Paleozoic basement. These envelopments thrust upward crosscut the allochthonous wedge, including, in the western zone of the chain, the upper Miocene wedge-top basin deposits. Finally, we suggest that the two tectonic windows are the result of the formation of an E-W trending regional antiform, associated with a late S-verging back-thrust, that has been eroded and crosscut by Early Pleistocene normal faults.</p>

Spatiotemporal palaeodiversity patterns of modern crocodiles (Crocodyliformes: Eusuchia)

2019 ◽  
Vol 189 (2) ◽  
pp. 635-656 ◽  
Author(s):  
Ane De Celis ◽  
Iván Narváez ◽  
Francisco Ortega
Keyword(s):  
South America ◽  
Least Squares ◽  
Late Miocene ◽  
North American ◽  
Fossil Record ◽  
Generalized Least Squares ◽  
Global Scale ◽  
Biotic Factors ◽  
Species Dynamics ◽  
Over Time

Abstract Eusuchia is a crocodyliform clade with a rich and diverse fossil record dating back to the Mesozoic. There are several recent studies that analyse crocodyliform palaeodiversity over time, but none of them focuses exclusively on eusuchians. Thus, we estimated subsampled eusuchian palaeodiversity species dynamics over time not only at a global scale, but also by continents and main crocodylian lineages (Alligatoroidea, Crocodyloidea and Gavialoidea). These estimates reveal complex spatiotemporal palaeodiversity patterns, in which two maxima can be detected: the first during the Palaeocene and the second, which is also the biggest, in the middle-late Miocene. The Palaeocene shift is related to a North American alligatoroid diversification, whereas the middle–late Miocene maximum is related to a diversification of the three main Crocodylia lineages in Gondwanan land masses, but especially in South America. Additionally, a model-based study using generalized least squares was carried out to analyse the relationships between different abiotic and sampling proxies and eusuchian palaeodiversity. The results show that palaeotemperature is the most important factor amongst the analysed proxies, in accordance with previous studies. However, the results suggest that, along with palaeotemperature, other abiotic and/or biotic factors might also be driving eusuchian palaeodiversity dynamics.

A new fairy armadillo (Cingulata, Chlamyphorinae) from the upper Miocene of Argentina: first fossil record of the most enigmatic Xenarthra

2019 ◽  
Vol 39 (5) ◽  
pp. e1716778 ◽  
Author(s):  
Daniel Barasoain ◽  
Rodrigo L. Tomassini ◽  
Alfredo E. Zurita ◽  
Claudia I. Montalvo ◽  
Mariella Superina
Keyword(s):  
Fossil Record ◽  
Upper Miocene

scholarly journals Naticid gastropod and octopodid cephalopod predatory traces: evidence of drill holes on the leucosid crab Ristoria pliocaenica (Ristori, 1891), from the Pliocene of the “La Serra” quarry (Tuscany, Italy)

10.4081/19 ◽  
2012 ◽  
Vol 153 (2) ◽  
pp. 257 ◽  
Author(s):  
Giovanni Pasini ◽  
Alessandro Garassino
Keyword(s):  
Fossil Record ◽  
Direct Evidence ◽  
Central Italy ◽  
Decapod Crustaceans ◽  
Early Pliocene ◽  
First Report ◽  
Predatory Activity ◽  
The Common ◽  
Drill Holes

Garassino<em> et al.</em> (2012) reported on a rich community of decapod crustaceans including axiideans, gebiideans, anomurans, and brachyurans from the Zanclean (Early Pliocene) of the “La Serra” quarry near San Miniato (Pisa, Tuscany, central Italy). In this decapod-rich assemblage some carapaces of the common pebble crab<em> Ristoria pliocaenica</em> (Ristori, 1891) (<em>Leucosiidae Samouelle</em>, 1819) are drilled in characteristic ways, due to the predatory activity of individuals belonging to two different taxa of marine clades, possibly naticids (Gastropoda, Naticoidea), and to octopodids (Cephalopoda, Octopoda). This is the first report of direct evidence of predation by cephalopods on crabs in the fossil record.

An enigmatic blastozoan echinoderm fauna from central kentucky

2009 ◽  
Vol 83 (5) ◽  
pp. 739-749 ◽  
Author(s):  
Colin D. Sumrall ◽  
Carlton E. Brett ◽  
Troy A. Dexter ◽  
Alexander Bartholomew
Keyword(s):  
North America ◽  
Northwest Territories ◽  
Middle Devonian ◽  
Fossil Record ◽  
Foreland Basin ◽  
Late Ordovician ◽  
Upper Devonian ◽  
Range Extension ◽  
First Report ◽  
Appalachian Foreland

A series of small road cuts of lower Boyle Formation (Middle Devonian: Givetian) near Waco, Kentucky, has produced numerous specimens of three blastozoan clades, including both “anachronistic” diploporan and rhombiferan “cystoids” and relatively advanced Granatocrinid blastoids. This unusual assemblage occurs within a basal grainstone unit of the Boyle Limestone, apparently recording a local shoal deposit. Diploporans, the most abundant articulated echinoderms, are represented by a new protocrinitid species, Tristomiocystis globosus n. gen. and sp. Glyptocystitoid rhombiferans are represented by isolated thecal plates assignable to Callocystitidae. Three species of blastoids, all previously undescribed, include numerous thecae of the schizoblastid Hydroblastus hendyi n. gen. and sp., the rare nucleocrinid Nucleocrinus bosei n. sp., and an enigmatic troosticrinid radial. The blastoid Nucleocrinus is typical for the age; however, the callocystitid, schizoblastid, and protocrinitid are not. Hydroblastus is the oldest known schizoblastid. Middle and Upper Devonian callocystitids have been previously reported only from Iowa and Michigan USA with unpublished reports from Missouri USA and the Northwest Territories, Canada. This occurrence is thus the first report of a Middle Devonian rhombiferan from the Appalachian foreland basin. Tristomiocystis is the first known protocrinitid in North America and the only protocrinitid younger than Late Ordovician. This occurrence thus represents a range extension of nearly 50 million years for protocrinids. This extraordinary sample of echinoderms in a Middle Devonian limestone from a well-studied area of North America highlights the incompleteness of the known fossil record, at least in fragile organisms such as echinoderms.

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