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STEPHANORHINUS KIRCHBERGENSIS (J"AGER, 1839) FROM THE MIDDLE PLEISTOCENE DEPOSIT OF RIANO (ROME, CENTRAL ITALY)
Full text linkNew and revised occurrences of Dihoplus megarhinus (Mammalia, Rhinocerotidae) in the Pliocene of Italy
No full textSeveral rhinoceros remains, collected in the Pliocene deposits of Northern Italy and usually ascribed to Dicerorhinus or Rhinoceros megarhinus, are revised; furthermore, unpublished Pliocene remains are also described. The material is compared with the respective anatomical elements of Dihoplus megarhinus, Stephanorhinus jeanvireti and Stephanorhinus etruscus. Based on morphological and morphometrical comparisons, the presence of Dihoplus megarhinus is confirmed in at least ten sites. In other Late Pliocene fossiliferous localities, the presence of S. jeanvireti and/or S. etruscus is recorded. D. megarhinus occurred in Italy at the beginning of the Early Pliocene. It was well represented in Val di Pugna (Tuscany) and in several Pliocene marine deposits near Bologna by fragmentary mandibles, some postcranial remains and few teeth. The species disappeared before the beginning of the Villafranchian (Late Pliocene) when S. jeanvireti and S. etruscus co-occurred both in the site of Villafranca d’Asti and Montopoli. S. jeanvireti disappeared in Italy at the Pliocene-Early Pleistocene transition whereas S. etruscus was widespread in Central and Southern Italy
Le Arenarie del M.Gottero nella sezione di Punta Mesco (Campaniano Sup.-Paleocene Inf., Appennino Settentrionale): analisi stratigrafica e petrografica della parte prossimale di un sistema torbiditico
No full textThe Mt. Gottero Sandstone of Punta Mesco area (Late Campanian-Early Paleocene, Northern Apennines): stratigraphic and petrographic analisys of the inner part of a deep sea fan. The Mt. Gottero Sandstone (Late Campanian-Early Paleocene) is remanents of the sedimentary cover of the Ligure-Piemontese oceanic lithosphere consisting of a thick siliciclastic turbidite system interpreted as a deep sea fan. The Mt.Gottero sandstone that crops out in the Punta Mesco area (Eastern Liguria) represents the inner part of the turbidite system characterized by the presence of high density turbidity current derived deposits (F4 to F8 Mutti's 1992 facies) and impact features.
The provenance of Gottero Sandstone from the Punta Mesco area has been investigated by petrographic modal analysis of arenites and conglomerates. A detailed analysis of conglomerate lithic fragments has also been performed.
According to previous works, arenites detrital mode of the Mt. Gottero Sandstone is quartz-feldspathic (Q50F33L17). The lithic fragments are mainly derived by granitoids, low grade metamorphic rocks and acidic volcanics; minor calcareous extrabasinal clasts are also present. Ophiolite derived rock fragments are absent. The petrographic parameters indicate a continental basament terrain as probable source area characterized by the exposure of large crystalline massif
La successione dell'Unità Due Ponti (Unità Liguri Interne, Appennino Settentrionale): evidenze du un'area sorgente carbonatica nelle successioni torbiditiche cretaciche della Tetide Occidentale
No full textStratigraphy and petrography of arenites from the Canale Fm. (Due Ponti Unit; Internal Liguride units) has been investigated. The sedimentary succession, more than 400m thick, is characterized by a pelitic-arenaceous turbidite sequence not older than Late Santonian. Facies analysis and sedimentological features indicate a deposition in a basin plain and/or lobe fringe setting.
In the uppermost part of the sequence several metric intercalations of pebbly mudstone (olistostrome Auctt.) made up of Palombini Shale-derived clasts are present. The pebbly mudstones are sometimes associated to structureless arenitic beds characterized by the same composition.
On the basis of composition, a/p ratio and sedimentological features, two different kinds of beds have been recognized in the turbidite succession of the Canale Fm.: "lithoarenitic beds" (forming more than 80% of the turbidite sequence) and "calcareous beds".
The framework of lithoarenitic beds includes not younger than Early Cretaceous platform derived carbonate grains (mainly oolitic- and peloidal-grainstones), acidic volcanic fragments (mainly rhyolite and rhyodacite) and crystalline s.l. grains (mainly derived from plutonic and Low grade metamorphic rocks). The "lithoarenitic beds" are characterized by a lithoarenitic composition (Q36-F14-L+C50) that indicate a sharp difference with the siliciclastic composition of the Gottero Sandstone (Q47-F34-L+C19).
Comparison of modal analysis from Canale Fm. arenites and Gottero Sandstone suggests the presence of multiple source areas for Late Cretaceous internal liguride turbidite deposits, that supplied different fan systems characterized by different compositional features.
Petrographic data from lithoarenitic beds of the Canale Fm. suggest a "European continental margin" derived source area showing strong affinity with the Briançonnese and Pre-Piemontese domains outcropping in Corsica and in the Sestri-Voltaggio Zone (cf. Trias-Lias Unit).
The presence of Palombini Shale-derived pebbly mudstones at the top of the investigated sedimentary succession indicate a sharp change in facies associations and petrographic composition that can be recognized in several Internal Liguride units (e.g. Bocco Shale; Colli/Tavarone Fm. and Lavagnola Fm.). This change represents a regional event indicating a crucial point during the paleogeographic and paleotectonic evolution of the Internal Liguride Domain related to the presence of the Eoalpine accretionary wedge. This morphotectonic element can be considered as the main source area for the upper part of the Internal Liguride successions
Il cranio di Stephanorhinus hemitoechus (Falconer, 1859) di Fosso Malafede (Vitinia, Roma) con note sulla prima presenza della specie in Italia
No full textSTEPHANORHINUS KIRCHBERGENSIS (J"AGER, 1839) FROM THE MIDDLE PLEISTOCENE DEPOSIT OF RIANO (ROME, CENTRAL ITALY)
No full textNew insights into the Oligocene Rhinocerotoidea (Mammalia, Perissodactyla) from Northwestern Italy
No full text
Taxonomy and phylogeny of the smallest Miocene rhinocerotid Parvorhinus n. gen. (Mammalia, Rhinocerotidae)
Full text linkMiddle Miocene Rhinocerotini are particularly important to understand the origin and evolution of latest Miocene and then PlioPleistocene taxa. However, little is known about some early divergent Rhinocerotina such as 'Dicerorhinus' steinheimensis. A sample of a small-sized rhinocerotid from the Middle Miocene (Mammal Neogene Zone 6) locality of Devi ' nska NovaVes (Bratislava, Slovakia) is here described for the first time. The specimens consist of maxillae, fragment of mandibles and postcranial remains. The described specimens clearly differ from Middle Miocene representatives of elasmotheres, aceratheres and brachypotheres, but closely resemble the poorly known rhinocerotid 'Dicerorhinus' steinheimensis. A cladistic analysis shows that this taxon is related with the early divergent Rhinocerotina, such as Lartetotherium sansaniense and Gaindatherium browni, and it is distantly related with both Rhinoceros and Dicerorhinus. Considering the position and the peculiar morphological and morphometric features, such as smaller size with respect to other Rhinocerotini species, posterior border of the symphysis in front of p2, crochet always present on P2-P4, P1 always absent, protoloph interrupted on P2, lingual cingulum absent on M1-M2, posterior part of the ectoloph concave on M1-M2, 'Dicerorhinus' stei
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