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The Newark Supergroup (Late Triassic - Early Jurassic) of eastern North America is world-famous for it's fossil footprint assemblages. Footprints are the most common tetrapod fossils from these strata. The field of ichnology owes it's existence to the pioneering work of Edward Hitchcock who, beginning in the 1830s, named and described Newark Superg...
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... was first described from eastern North America (Bock 1952), but has received no scrutiny since the 1950s. Apatopus lineatus is the only ichnospecies of this ichnogenus (Figure 7). A redescription of the holotype and paratypes, all from a single quarry in Milford, NJ, enabled comparison with specimens referred to this ichnotaxon from other localities (of slightly younger ages within the Late Triassic) in New Jersey ( Osborne and Rainforth 2006). ...
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Mass extinctions change global ecosystems, and the end‐Triassic mass extinction was hypothesized to have precipitated the rise of dinosaur dominance, with dinosaurs filling resource zones of eliminated large‐bodied reptilian lineages. This replacement has been explicitly hypothesized for theropod dinosaurs, and the eastern North American theropod f...
The discovery of sauropod trackways in the Late Jurassic (Tithonian) of the Jura department (eastern France) is reported. More than 170 footprints (pes and manus prints) comprise at least nine trackways. The footprints are referred to the ichnogenus Parabrontopodus, characterized by a narrow-gauge trackway. The locality of Coisia is the most import...
Citations
... Each data case is either the mean for a trackway, or the value for an isolated print. from around the world (Calvo, 1991;Lockley and Meyer, 2000;Thulborn, 2001;Farlow and Galton, 2003;Calvo and Mazzetta, 2004;Clark et al., 2004;Day et al., 2004;Diedrich, 2004Diedrich, , 2011Gangloff et al., 2004;Barco et al., 2005Barco et al., , 2006Getty, 2005;Huh et al., 2006;Li et al., 2006;Lü et al., 2006;Lucas et al., 2006;Gand et al., 2007;Lockley et al., 2007Lockley et al., , 2008Lockley et al., , 2011Lockley et al., , 2013, c, e, 2015bRainforth, 2007;Wings et al., 2007;Bessedik et al., 2008;Fujita et al., 2008;Boutakiout et al., 2009;Sullivan et al., 2009;Belvedere et al., 2010;Li et al., 2010;Niedźwiedzki, 2011;Nouri et al., 2011;Xing et al., 2011b, c;, b, c, d, e, f, h, 2015a, c, e, 2016Moreau et al., 2012Moreau et al., , 2014Wagensommer et al., 2012;Fiorillo et al., 2014;McCrea and Pigeon, 2014;McCrea et al., 2014a, b;Foster, 2015;Li et al., 2015;Lallensack et al., 2015;Weems and Bachman, 2015). Criteria used to discriminate among these footprint taxa include relative toe lengths, angles between toes, the footprint width/length ratio, the extent to which the distal impression of digit III extends beyond the distal impressions of digits II and IV, the shape of a triangle defined by the tips of the marks of digits II-IV, and the configuration of the back of the footprint. ...
The transect from Jones Ranch Quarry, west of the town of Glen Rose, to the Arlington Archosaur Site, in the heart of the Dallas-Fort Worth Metroplex, spans 20 million years of the middle Cretaceous. These sediments lie at the base of a larger section in north-central Texas with near continuous sedimentation to the end of the Maastrichtian. At an even grander scale this is a small part of Cretaceous strata that crop out extensively across the state, forming a broad band roughly parallel with the present day coast of the Gulf of Mexico. This field trip visits Cretaceous strata in the Fort Worth Basin, that is one of the main archosaur fossil-bearing regions of the state.
... has been generally assigned to phytosaurs (Baird, 1957; Olsen and Huber, 1998; Foster et al., 2003; Rainforth, 2007; Padian et al., 2010). This interpretation was based on general similarities between the trackway of Apatopus and those of living crocodilians, the correspondence of phytosaur skeletons with those reconstructed from Apatopus trackways, and the overlapping stratigraphic range with phytosaurs. ...
Diverse tetrapod track assemblages with Scoyenia invertebrate traces were discovered in the Triassic Timezgadiouine and Bigoudine formations of the Argana Basin (Western High Atlas, Morocco). The ichnofossils occur in alluvial plain sandstones and mudstones of the Irohal`ene Member (T5) and Tadart Ouadou Member (T6) considered Carnian-Norian in age by vertebrate remains and palynomorphs. Tetrapod footprints are assigned to
Apatopus, Atreipus-Grallator, Eubrontes isp., Parachirotherium, cf. Parachirotherium postchirotherioides, Rhynchosauroides ispp., and Synaptichnium isp. They can be referred to lepidosauromorph/archosauromorph, basal archosaur, and dinosauromorph trackmakers. Apatopus, represented by 11 tracks of a more than 4 m
long trackway, is recorded for the first time outside of North America and Europe. The assemblage concurs with the proposed Late Triassic age of the track-bearing beds by the occurrence of Apatopus, Atreipus-Grallator, and Eubrontes. If this is accepted, the stratigraphic range of Synaptichnium and Parachirotherium, hitherto known only from Early orMiddle Triassic deposits, has to be extended to the Carnian-Norian. The occurrence of Eubrontes
in the Irohalene Member (T5) provides further evidence for large theropods in pre-Jurassic strata. All assemblages are referred to the Scoyenia ichnofacies indicating continental environments with alternating wet and dry conditions.
The tridactyl ichnotaxon Eubrontes giganteus commonly has been attributed to a carnivorous theropod dinosaur similar to Dilophosaurus or Liliensternus. For this to be correct, however, at least five unusual circumstances all must be true. (1) If the Eubrontes track-maker was a theropod, it created the most abundant large tracks found in the Connecticut Valley Hartford and Deerfield basins and yet, for unknown reasons, left no skeletal remains there at all. This pattern also holds true for the Kayenta Formation and Navajo Sandstone in the American Southwest. (2) The cursorial, bipedal, functionally tridactyl prosauropod Anchisaurus, which left two-thirds of the skeletal remains found in these same basins, for unknown reasons left no tracks there at all. (3) If the Eubrontes track-maker was a theropod, by happenstance, it was a theropod exactly the same size as Anchisaurus. (4) If the Eubrontes track-maker was a theropod, then published evidence for herding by Eubrontes track-makers must be due to local paleogeographic factors, not recognizable in the rock record, which created an illusion of herding. (5) The known stratigraphic range of Eubrontes tracks (Norian-Toarcian) by happenstance falls entirely within the known stratigraphic range of bipedal prosauropods (upper Carnian-Toarcian). None of these unusual circumstances need be true, however, if Anchisaurus was the Eubrontes track-maker. Recent reports of an anteriorly directed hallux in the Eubrontes track-maker provide compelling evidence that prosauropods, not theropods, made Eubrontes tracks. Parsimony strongly favors this conclusion and weighs heavily against the idea that the Eubrontes track-maker was a mysterious, elusive theropod whose skeletal remains have evaded discovery for nearly two centuries. © 2019
This paper describes open-source hardware to measure both the magnitude and phase of the electrical bioimpedance in a frequency range from few kilohertz up to 100 kHz by using a four-electrode technique. The amount of current injected and the sensitivity of the system can be set to the desired range by changing the front-end resistor values. The system can be easily built and adapted with the help of the design details made available at GitHub. The practical performance was evaluated in abdominal impedance measurement, which was the primary motivation to build the system. Other experiments were performed with a 2R-1C circuit, a 10-Ω resistor, and a 100-nF capacitor, with observed relative errors in the impedances of -0.73 ± 0.34 %, -2.47 ± 1.43 % and -8.81 ± 0.64 % (mean ± SD), respectively, from 10 kHz to 100 kHz.
The tetrapod ichnotaxon Apatopus lineatus is a relatively uncommon component of Late Triassic footprint assemblages. This might be related to the semi-aquatic lifestyle of the trackmakers, which were almost certainly phytosaurs and whose skeletons are known from coeval deposits with a Pangea-wide distribution. Originally described from the Passaic Formation of New Jersey, Apatopus lineatus has been reported from other localities and horizons in the Newark Supergroup and from the Chinle Group of the American Southwest. In recent years, new discoveries of Apatopus footprints and trackways have been made in North America, North Africa and Europe. A footprint with skin impressions from the Passaic Formation of Pennsylvania and material from the Stuttgart and Hassberge formations (Carnian) of Germany is described here for the first time. Parallel to the osteological record of phytosaurs, the ichnotaxon Apatopus lineatus reflects a widespread group of archosaurs living in habitats that only randomly overlapped those of fully terrestrial chirotherian trackmakers. The re-evaluation of the phylogenetic position of phytosaurs in recent studies and the supposed stratigraphic range of Phytosauria from the Early to the Late Triassic suggest a terrestrial lifestyle for early members of the group and a later adaptation to aquatic environments, similar to the evolutionary developments in crocodylomorphs that took place in the Jurassic-Cretaceous. Morphologically and temporally, some chirothere footprints from Early-Middle Triassic deposits such as Synaptichnium could fill this gap in the early record of Phytosauria.
