The Late Triassic—Early Jurassic ichnofauna described mainly by Paul Ellenberger from southern Africa (Lesotho) is a valuable window on first phases of dinosaur diversification. Unfortunately, the present taxonomic status of several forms from that ichnofauna is unclear. The revision of this material has been frequently invoked and partially done without reaching many definitive results. Due to the enormous amount of data, a global revision seems at present impossible and must be accomplished in smaller steps. A small number of Ellenberger's ichnogenera including Tetrasauropus, Pseudotetrasauropus, Pentasauropus, Paratetrasauropus, Sauropodopus and Deuterosauropodopus, which different authors have ascribed to basal sauropodomorphs, are here revised in a consistent manner and their attribution to osteological clades is considered. Tetrasauropus and Pseudotetrasauropus are here validated as the only ichnotaxa related to sauropodomorphs. Pentasauropus is retained as valid, and a therapsid trackmaker is suggested. Paratetrasauropus and Sauropodopus are also validated and ascribed to non-dinosaurian trackmakers, and Deuterosauropodopus is synonymized with Sauropodopus.
SUMMARY - Atreipus-like footprints and their co-occurrence with Evazoum from the upper Carnian (Tuvalian) of Trentino-Alto Adige A new Tuvalian (Carnian) tetrapod ichnocoenosis is described from Trentino-Alto Adige (Northeastern Italy). The outcrop has yielded Atreipus-like and Evazoum-like footprints along with grallatorids and crurotarsan ichnites. Atreipus appears for the first time in the Italian ichnologic record while Evazoum co-occurs with Atreipus uniquely in this outcrop. The ichnocoenosis gives new insights on the palaeogeographic distribution and biochronologic significance of Atreipus and Evazoum. RIASSUNTO - Orme Atreipus-like e loro compresenza con Evazoum dal Carnico superiore (Tuvalico) del Trentino-Alto Adige - Viene descritta una nuova icnocenosi a tetrapodi dal Tuvalico del Trentino-Alto Adige (Italia Nordorientale). L’affioramento ha restituito orme tipo Atreipus e tipo Evazoum assieme a impronte grallatoridi e di crurotarsi. Atreipus compare per la prima volta nel record icnologico italiano, mentre Evazoum si trova in associazione con Atreipus esclusivamente in questo affioramento. L’icnocenosi fornisce nuove informazioni sul significato biocronologico e sulla distribuzione paleogeografica di Atreipus e Evazoum.
In two contiguous quarries located south of Mt. Magaggiaro, in the Sciacca region (south-western Sicily), a discontinuous pelagic succession is exposed, overlying the lower to (?) middle p.p. Early Jurassic peritidal limestone of the Inici Fm. The area belongs to the palaeogeographic Saccense Domain. Posidoniids-rich pelagites, late Bajocian in age, generally overlie directly the peritidal limestone; the base of the pelagic succession corresponds to, and is concordant with, a planar surface that truncates tilted beds of the Inici Fm. A thin condensed horizon, exceptionally rich in ammonites and belemnites, is however locally interposed between the peritidal limestone and the Bajocian pelagic deposits. It bears a mixed ammonite assemblage indicating a late Toarcian (D. meneghini biozone) to middle Aalenian age. The biochronological meaning of this horizon serves to constrain better the drowning event that affected the platform. The angular nature of the unconformity, corresponding to a drowning unconformity, is interpreted as the product of synsedimentary extension that predated the drowning of the Inici platform.
We report here on the first tetrapod tracks from the Triassic of the Nurra region (north-western Sardinia, Italy). The specimens were found on sandstone blocks used to build a fence limiting a seasonal camping, in the coastal area north of Capo Caccia promontory. Lithologic and petrographic features allowed an assignment of the track-bearing blocks to the middle-upper portion of the Anisian (Middle Triassic) Arenarie di Cala Viola (Buntsandstein). Footprints are attributed to the ichnotaxa Rhynchosauroides and Rotodactylus, two common ichnotaxa of late Early Triassic and Middle Triassic ichnofaunas of Europe and United States, commonly referred in the literature to neodiapsid and archosaur producers, respectively.
Nel 2016 ricorreva il centenario della nascita di Bruno Accordi, figura centrale per geologia romana e italiana a partire dalla seconda meta del secolo scorso. Tra i diversi contributi e materie analizzatein una lunga carriera 'vecchio stampo', realmente caleidoscopica e onnivora, Accordi ha avuto anche il merito di aver rilanciato per primo l'interesse per le radici identitarie delle nostre discipline in Italia. A partire dagli anni sessanta del secolo scorso, Accordi ha pubblicato sistematicamente sulla rivista Geologica Romana, giornale da egli stesso fondato nel 1962 per rendere noti i nuovi progressi fatti nello studio dell'Appennino, numerosi contributi su figure italiane centrali per il primo avanzamento delle Scienze della Terra sensu lato.Il presente contributo vuole essere un tributo al grande geologo e alla sua opera in campo della Storia della Scienza, che lo vide impegnato e appassionato negli ultimi anni di vita, lasciando un esempio da seguire e solide fondamenta per studi futuri in materia.
In the Nurra region (NW Sardinia), along the coast that stretches from Cala Viola to Cala del Turco bays, a stratigraphic sequence of continental sediments ranging from the upper Paleozoic to the lower Mesozoic is wonderfully exposed. In the last twenty years this area has been a subject of renewed studies due to its exceptional stratigraphic and sedimentological features and thanks also to an exceptional paleontological record, encompassing trace fossils and body fossils, which provided key chronological data. The most recent investigations have been focused on stratigraphic and structural geology aspects, allowing to reconstruct the tectonic evolutionary history of Sardinia, from the middle Permian up to the Middle Triassic. The redefinition of the stratigraphic and structural framework of the area became possible through integrating traditional geological surveys (mainly, field mapping, facies and structural analyses) with analyses conducted on 3D digital models of outcrops (DOMs) obtained via drone-based aerophotogrammetry. Investigations, both in the field and computer-based, have enabled the identification of the arrangement of cross-cutting relationships among fault systems. Despite the absence of absolute geochronological constraints (e.g., dating of syn-kinematic mineralizations), it has nevertheless been possible to identify at least six to eight deformational events. These analyses have revealed the likely history of deformational processes in this sector of the Island, highlighting the tectonic events that have occurred from the Permian until at least the Pliocene, despite Pleistocene-Holocene tectonics cannot be excluded. The events can be summarized as follows: Event 1: extensional tectonics related to the angular unconformity between Permian and Triassic deposits (age post early middle Permian to Early Triassic) Event 2: extensional tectonics related to the rifting of the Ligurian-Piedmont Ocean and subsequent carbonates deposition (Middle Jurassic: Bajocian-Bathonian) Event 3: extensional event related to the early Pyrenaic deformation and represented by an extensive angular unconformity/hiatus in carbonate platform (Early Cretaceous: Aptian-Albian) Event 4: transpressive and compressive event related to deformative phase called “Laramian” tectonics (Late Cretaceous) Event 5: compressive and consequent transcurrent tectonics related to the “Pyrenaic phase” (Eocene to Aquitanian age) Event 6: extensional tectonics related to the opening of the Balearic basin and the rotation of the Sardinia-Corsica block (Burdigalian age) Event 7: extensional tectonic phases occurred during two different sub-events (Serravalian age and the Pliocene age) Event 8: extensional event occurred during the Pleistocene-Holocene
