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Italian notosuchian and other new papers
From: Ben Creisler
A few new (and not so new) papers that may not have mentioned on the DML:
FABIO M. DALLA VECCHIA & ANDREA CAU (2011)
THE FIRST RECORD OF A NOTOSUCHIAN CROCODYLIFORM FROM ITALY.
Rivista Italiana di Paleontologia e Stratigrafia 117 (2)
A serrated tooth from the Coniacian-Santonian (Upper Cretaceous) Polazzo
fossil site (Karst, NE Italy) is the first record of a notosuchian
crocodyliform from Italy. Although it shares synapomorphies with teeth
referred to the European genus Doratodon and with the Gondwanan genus
Araripesuchus, it is distinct in the unusual combination of features,
suggesting the presence of a yet unreported notosuchian taxon in the
Adriatic-Dinaric Carbonate Platform located in the Tethys between the
Afroarabian continent and the North European landmass during Late
Cretaceous times. Notosuchians were typically terrestrial crocodyliforms,
supporting the presence of emergent areas on the carbonate platform.
Attila Osi; Jozsef Polfya; Loszlo Makdi; Zoltan Szentesi; Peter Gulyes;
Marton Rabi; Gabor Botfalvai; Kinga Hips (2011)
Hettangian (Early Jurassic) Dinosaur Tracksites from the Mecsek Mountains,
Ichnos 18(2): 79-94
Isolated theropod dinosaur tracks were first collected in Hungary from
Hettangian (Lower Jurassic) beds of the Mecsek Coal Formation in 1966 and
described as Komlosaurus carbonis Kordos, 1983. Our study is based on newly
collected material from additional track-bearing beds. The description of
the two largest preserved surfaces containing a total of 102 tracks that
can be referred to as 21 trackways is provided here. This represents the
first attempt to measure, map and compare the tracks of these bipedal,
functionally tridactyl dinosaurs in several associated trackways.
Significant morphological variability can be observed (e.g., depth,
presence or absence of a metatarsal impression, digit length, digit
divarication angle) that is explained by differences in physical parameters
of the substrate. The mean of pes length is 16.3 cm in tracksite PB1 and
19.9 cm in tracksite PB2. Stride length of trackways usually ranges between
120 and 170 cm; pace angulation is 160-175°. The speed of the trackmaker is
calculated to range between 6 and 14 km/h. Imprints are diagnosed by a pes
length/width ratio lower than 2.0; metatarsal pads and hallux impressions
are frequent. Based on the similarity of several morphological characters,
the herein described tracks are referred to the ichnotaxon Komlosaurus
carbonis, which is clearly distinct from Grallator and Kayentapus.
David Peters (2011)
A catalog of pterosaur pedes for trackmaker identification.
The matching of ichnites to extinct trackmakers has been done successfully
with a variety of taxa, from basal hominids to basal tetrapods. Traces
attributed to pterosaurs have been studied for more than 50 years, but
little interest has been shown in the pedes themselves. While ichnites can
vary greatly in their correspondence to their trackmaker, most pterosaur
tracks appear to preserve sufficient detail to assess their origins. This
report presents a catalog of pterosaur pedal skeletons that can be matched
to a wider spectrum of ichnites, including digitigrade and bipedal ichnites
previously not associated with pterosaurs. A variety of pedal characters
separate several putative genera into distinct clades, some only distantly
related to one another. Distinct pedal characters indicate certain tiny
pterosaurs were not juveniles of dissimilar adults, but were separate taxa
and likely adults themselves. A squamate and fenestrasaur origin for
pterosaurs is supported. These new insights overturn long-standing
paradigms. The pterosaur pes contains a wealth of data that should not be
ignored. Application of this data enables a more precise identification of
both skeletal taxa and ichnotaxa.
A paper that's been out for a month or so:
DIEDRICH, C. G. (2011)
Middle Triassic horseshoe crab reproduction areas on intertidal flats of
Europe with evidence of predation by archosaurs.
Biological Journal of the Linnean Society103: 76?105.
A systematically excavated track site in a 243.5 Myr old Middle Triassic
(Karlstadt Formation, Pelsonian, middle Anisian) intertidal carbonate
mud-flat palaeoenvironment at Bernburg (Saxony-Anhalt, central Germany) has
revealed extensive horseshoe crab trackways attributable to the
Kouphichnium Nopsca, 1923 ichnogenus. The exposed track bed of a Germanic
Basin-wide spanned intertidal megatrack site is a mud-cracked biolaminate
surface on which detailed tracks have been preserved because of rapid
drying and cementation as a result of high temperatures, followed by rapid
covering with a protective layer of arenitic storm or tsunami sediments.
The different trackway types and their orientations have allowed a tidal
sequence to be reconstructed, with the initial appearance of swimming
horseshoe crabs followed by half-swimming/half-hopping limulids under the
shallowest water conditions. The Bernburg trackways, which have mapped
lengths of up to 40 m, were all produced by adult animals and exhibit a
variety of shapes and patterns that reflect a range of subaquatic
locomotion behaviour more typical of mating than of feeding activities. The
closest match to the proportions and dimensions of the horseshoe crab
tracks at Bernburg is provided by the largest known Middle Triassic limulid
Tachypleus gadeai, which is known from the north-western Tethys in Spain.
The horseshoe crab body fossils recognized in the German Mesozoic
intertidal zones, instead, are from juveniles. The uniformly adult size
indicated by the trackways therefore suggests that they may record the
oldest intertidal reproductive zones of horseshoe crabs known from anywhere
in the world, with the track-makers having possibly migrated thousands of
kilometres from shallow marine areas of the north-western Tethys to
reproduce in the intertidal palaeoenvironments of the Germanic Basin.
Chirotherium trackways of large thecodont archosaurs also appeared on these
flats where they appear to have fed on the limulids. With the tidal ebb,
smaller reptiles such as Macrocnemus (Rhynchosauroides trackways) appeared
on the dry intertidal flats, probably feeding on marine organisms and
possibly also on horseshoe crab eggs.
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