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[dinosaur] Dinosaur tracks from Italy and Portugal + Triassic tracks from South Africa + birdlike tracks from Morocco (free pdfs)




Ben Creisler
bcreisler@gmail.com


The most recent issue of Bollettino della Società Paleontologica Italiana is in open access and has a number of dinosaur and vertebrate ichnology articles:

http://paleoitalia.org/archives/bollettino-spi/92/vol-56-2-2017-open-access/

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Emese M. Bordy, Miengah Abrahams & Lara Sciscio (2017)
The Subeng vertebrate tracks: stratigraphy, sedimentology and a digital archive of a historic Upper Triassic palaeosurface (lower Elliot Formation), Leribe, Lesotho (southern Africa). 
Bollettino della Società Paleontologica Italiana 56: 181-198.
doi:10.4435/BSPI.2017.12 
http://paleoitalia.org/media/u/archives/08_Bordy_et_al_2017_BSPI_562.pdf


Dinosaur vertebrate body and ichnofossils are relatively abundant in the Upper Triassic-Lower Jurassic Elliot Formation (Stormberg Group, Karoo Supergroup) in the main Karoo Basin in southern Africa. Herein we present the results of our sedimentological, stratigraphical and ichnological investigations at a historic ichnosite in NE Lesotho that is among the first documented vertebrate track-bearing palaeosurfaces in southern Gondwana. After decades of neglect, the Subeng ichnosite is restudied in this paper in light of the advances in ichnological methods and the formalised stratigraphy of the Stormberg Group. Documentation of this ichnosite was conducted using a mix of field-based sedimentological and ichnological methods and photogrammetry, which collectively allowed us to place the site within the lowermost Elliot Formation (Upper Triassic). Our detailed palaeoenvironmental reconstruction, based on palaeocurrent measurements and sedimentary facies analysis of the host rocks, suggests that this diverse Upper Triassic assemblage of vertebrate ichnofossils, which is an integral part of the history of life on land just before the end-Triassic mass extinction event, formed near a shallow oxbow lake or drying up watering hole on the floodplain of a meandering river system. This water source attracted numerous bipedal and quadrupedal animals as attested by the presence of tridactyl, tetradactyl and pentadactyl tracks on the palaeosurface. We have also produced a photogrammetric digital 3D model (available online) of the Subeng ichnosite to serve as a digital replica and archive for further ichnological study. This digital documentation is important not only for the preservation of this rapidly eroding palaeosurface (situated in an active streambed), but also for the provision of a visually stimulating tool for community outreach and science education in rural African communities.




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Matteo Belvedere, Marco Franceschi, Francesco Sauro & Paolo Mietto (2017)
Belvedere M., Franceschi M., Sauro F. & Mietto P. (2017)
Dinosaur footprints from the top of Mt. Pelmo: new data for Early Jurassic palaeogeography of the Dolomites (NE Italy). 
Bollettino della Società Paleontologica Italiana 56: 199-206.
doi:10.4435/BSPI.2017.10
http://paleoitalia.org/media/u/archives/09_Belvedere_et_al_2017_BSPI_562.pdf

Dinosaur footprints from the Lower Jurassic of northeastern Italy are well known and, since the first discoveries in the early 1990s, many sites have been described. Tracks are mostly found in the peritidal limestones of the Calcari Grigi Group, deposited on the Trento carbonate platform, now cropping out in the Southern Alps. In 2011, a group of speleologists discovered a new tracksite in the Lower Jurassic Calcari Grigi Group exposed almost at the top of Mt. Pelmo (Dolomites), 3037 m above sea level. Footprints are generally poorly preserved, but it proved possible to recognise some tridactyl footprints with theropodian features (i.e., elongated digit III and narrow interdigital angle) and some possible quadruped tracks whose con guration resembles that of a sauropodomorph trackmaker. Careful examination of the depressions excludes their inorganic origin (chemical weathering). Despite the poor quality of the traces, the Pelmo site is significant because it is the most easterly site ever found on the Trento Platform and the only one which is located north of the Valsugana Fault. This fault system is a major alpine tectonic lineament that separates the classical successions of the Calcari Grigi Group in the Italian Prealps from those located in the Dolomites. Moreover, the discovery of the Pelmo tracks considerably expands the documented area of movement of Early Jurassic terrestrial vertebrates in the northern part of the Trento Platform, extending the size of the Early Jurassic megatracksites of the Southern Alps.

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Gierlinski G., Lagnaoui A., Klein H., Saber H., Oukassou M. & Charriere A. (2017) 
Bird-like tracks from the Imilchil Formation (Middle Jurassic, Bajocian-Bathonian) of the Central High Atlas, Morocco, in comparison with similar Mesozoic tridactylous ichnotaxa). 
Bollettino della Società Paleontologica Italiana 56: 207-215.
doi:10.4435/BSPI.2017.19 
http://paleoitalia.org/media/u/archives/10_Gierlinski_et_al_2017_BSPI_562.pdf


Small bird-like tracks have recently been discovered at three outcrops of the Imilchil Formation (Middle Jurassic, Bajocian- Bathonian) in the Central High Atlas of Morocco. The track-bearing strata are part of a marine-continental transitional succession, the studied surfaces being sandy marls and limestones of a brackish depositional environment. The footprints strongly resemble the ichnogenus Trisauropodiscus Ellenberger, 1970, from the Lower Elliot Formation (latest Triassic) of Lesotho, southern Africa and are assigned to Trisauropodiscus isp. These are functionally tridactyl, widely divaricated pes tracks with digit III being longest and a trace of the reverted digit I (hallux) being occasionally imprinted. In contrast to some former studies suggesting Trisauropodiscus as a junior synonym and extramorphological variation of the ornithischian ichnogenus Anomoepus, this ichnotaxon is considered here as a distinctive morphotype among similar theropod tracks found in Jurassic-Cretaceous ichnoassemblages. An amended diagnosis is proposed focusing on the features that are here discussed and considered as key characters of this ichnotaxon. An avian interpretation of the trackmaker is problematical, especially against the background of the stratigraphic range of Trisauropodiscus back to the Late Triassic. Presently, theropods with very bird-like feet are the more likely producers. Future analyses and comparison of Trisauropodiscus with pes skeletons of avian and non-avian theropods might enlighten this.

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Silvério Figueiredo, Pedro Dinis, João Belo, Pierluigi Rosina & Ioanna Bachtsevanidou Strantzali  (2017) 
A new record of a possible ornithopod footprint from the Lower Cretaceous of Cabo Espichel (Sesimbra, Portugal). 
Bollettino della Società Paleontologica Italiana 56: 217-231.
doi:10.4435/BSPI.2017.20
http://paleoitalia.org/media/u/archives/11_Figueiredo_et_al_2017_BSPI_562.pdf


Bollettino della Società Paleontologica Italiana, 56 (2), 2017, 217-231. Modena
We present a new dinosaur footprint from Praia do Guincho, Portugal. Praia do Guincho is a seaside locality, situated 2 km north of Cabo Espichel. A loose cast of a tridactyl dinosaur footprint was discovered during fieldwork in 2011. The cliff where the footprint was found is composed of limestones, marls, sandstones and conglomerates that were deposited in shallow marine, lagoon and estuarine environments. The succession belongs to the Papo-Seco Formation (Lower Cretaceous-Barremian). The remains of several groups of vertebrates, including dinosaurs, have been reported in this formation. This paper provides a trackmaker study consisting of a visual analysis under different light angles and photogrammetric 3D modelling. The specimen has a digit III longer than II and IV. However, a substantial part of the shape of digit III is sediment, giving a flawed impression that it belongs to the footprint itself. The photogrammetric modelling revealed that digit III is shorter and more rounded than it appeared to be in the first place and the morphology of the cast (large plantar surface, similar length and width rounded heel, with elongate, narrow digits) matches with the features of the pes of ornithopods and with the characteristics described as belonging to ornithopod dinosaurs.


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