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Two dinosaur track papers in the last issue of Ichnos

Hornung, J.J. & M. Reich. 2014. Metatetrapous valdensis Nopcsa, 1923
and the presence of ankylosaur tracks (Dinosauria: Thyreophora) in the
Berriasian (Early Cretaceous) of northwestern Germany. Ichnos,


Metatetrapous valdensis Nopcsa, 1923 from the late Berriasian of
northwestern Germany was the first dinosaur ichnotaxon ever attributed
to a thyreophoran trackmaker. However, the subsequent lost of the
original material made this identification and the status of the
ichnotaxon questionable for many subsequent authors. This situation
was aggravated by the fact that there are only very brief original
descriptions accompanied by a single drawing. A reconsideration of the
original description recognizes M. valdensis as a valid ichnotaxon,
which, albeit showing great resemblance in pes morphology to similar
ichnotaxa, stands out from them by a tetradactyl manus. It not only
holds its original systematic attribution, but also has sparked early
hypotheses on the phylogeny of dinosaurs already in 1922, possibly for
the first time based upon tracks. Two surviving natural hypichnial
casts of ankylosaurian pes imprints from the same stratum cannot be
straightforwardly identified with the type material due to a lack of
documentation. However, comprehensive circumstantial evidence,
including complete accordance in size and morphology among others,
strongly supports such an association. The tracks confirm the presence
of ankylosaurs in this lacustrine-deltaic setting as a very rare
element of the local dinosaur fauna.

Keywords: Ankylosauria, Early Cretaceous, Germany, Ichnotaxonomy, Metatetrapous


Alcala, L., F. Perez-Lorente, L. Luque, A. Cobos, R. Royo-Torres & L.
Mampel. 2014. Preservation of dinosaur footprints in shallow
intertidal deposits of the Jurassic-Cretaceous transition in the
Iberian Range (Teruel, Spain). Ichnos, 21(1):19-31.


This article describes the sedimentological characteristics of
dinosaur ichnites at three sites within the municipal area of El
Castellar (in the Province of Teruel, Aragon, Spain): El Castellar
(CT-1), El Pozo (CT-2), and Camino El Berzal (CT-3). These sites
possess large concentrations of footprints made by quadrupedal
(sauropod, stegosaurid and ornithopod) and bipedal theropod dinosaurs.
Among the more than 800 documented footprints at CT-1 is a trail left
by a large theropod, and at least one other made by a stegosaurid (the
holotype of Deltapodus ibericus). CT-3 contains some of the largest
sauropod footprints ever found in the Iberian Peninsula. The three
sites lie within the Villar del Arzobispo Formation, which was
deposited over the Tithonian-Berriasian period in an environment under
tidal influence. Tidal carbonates host the largest number of
footprints. Different footprint shapes and degrees of preservation are
apparent, even within a single layer, reflecting the characteristics
of the original sediment in which the footprints were made. The grain
size and water content of the original sediment, primarily the
micritic mud derived from the pellets when it contains some water,
appear to have been the most important factors in determining the
quality of the preserved prints. The presence of algal mats appear to
have been less important, because the mats detected inside the massive
or pelletoidal micrite were broken and deformed, andwould therefore
not have invested the substrate with cohesion enough to favor
footprint preservation.

Keywords: Dinosaur, Iberian range, Preservation, Tidal flat,
Tithonian-Berriasian, Tracksite, Villar del Arzobispo Formation

Jose Ignacio Ruiz-Omenaca
Museo del Jurasico de Asturias (MUJA)
E-33328 Colunga, Spain