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Special Issue on Lettenkeuper Upper Triassic beds in Germany (free pdfs)



Ben Creisler
bcreisler@gmail.com

The open-access German journal Palaeodiversity has published a special
supplement issue on the Lettenkeuper:

Special Issue: Der Lettenkeuper - ein Fenster in die Zeit vor den
Dinosauriern [The Letternkeuper-- a Window into the Time Before the
Dinosaurs]

http://www.palaeodiversity.org/currentissue.htm

The text is in German, but each article has an English abstract.

Three chapters in particular may be of interest to the DML:



Rainer R. Schoch (2015)
9. Amphibien und Chroniosuchier des Lettenkeupers  [Amphibians and
chroniosuchians from the Lettenkeuper]
Palaeodiversity 2015 Special Issue: Der Lettenkeuper - ein Fenster in
die Zeit vor den Dinosauriern: 203-230
http://www.palaeodiversity.org/pdf/08Suppl/09Palaeodiversity_SB_Schoch.pdf


The Lower Keuper is rich in temnospondyl amphibians, which are
abundant in many horizons. Isolated fangs and vertebrae are common
finds in lake and stream deposits. The largest known temnospondyl,
Mastodonsaurus giganteus, was also the first taxon of that group to be
discovered, now known by numerous size classes. It is accompanied in
some horizons by the 2–3 m long capitosaur Kupferzellia wildi, a
broad-snouted relative of Late Triassic Cyclotosaurus. In the last
decade, excavations at Vellberg yielded rich material of two new
temnospondyls, the gracile and slender-skulled trematosaurid
Trematolestes hagdorni and the short-snouted Callistomordax kugleri.
Both taxa are known from a broad range of sizes, documenting the whole
ontogeny of these fully aquatic tetrapods.
The Plagiosauridae, a small temnospondyl clade with fl attened skulls
and bodies, is present with four distinctive taxa: (1) the heavily
armoured Gerrothorax pulcherrimus, (2) the larger more highly-built
Plagiosuchus pustuliferus, (3) the broad-headed Plagiosternum
granulosum which dominates in the Grenzbonebed, and (4) Megalophthalma
ockerti from the Hauptsandstein, related to Plagiosternum but with a
longer skull and larger teeth.
Confined to a few horizons, the chroniosuchian Bystrowiella schumanni
forms the only other basal tetrapod taxon apart from temnospondyls.
Readily identified by its ball-and-socket joint between pleurocentrum
and the spherical intercentrum, this reptiliomorph taxon now forms one
of the best-preserved representatives of the group, which is otherwise
only known from Russia and Inner Asia.
=======


Rainer R. Schoch  (2015)
10. Reptilien des Lettenkeupers  [Reptiles of the Lettenkeuper]
Palaeodiversity 2015 Special Issue: Der Lettenkeuper - ein Fenster in
die Zeit vor den Dinosauriern: 231- 264
http://www.palaeodiversity.org/pdf/08Suppl/10Palaeodiversity_SB_Schoch.pdf


The reptile fauna of the Lower Keuper has recently been studied in
more detail, after a decade of excavation yielded rich finds from
numerous aquatic and terrestrial groups. The marine or brackish
reptiles encompass the sauropterygians Nothosaurus (4 species),
Simosaurus, Neusticosaurus, and Psephosaurus. Only known by its
vertebrae, the thalattosaur-like Blezingeria remains still enigmatic.
Tanystropheids are present with a large species of Tanystropheus and a
smaller taxon known by teeth and cervical vertebrae from lake
deposits. Amphibious and terrestrial reptiles are primarily known from
lake deposits such as Vellberg. The sickle-toothed Zanclodon laevis is
ranked as an archosauriform with uncertain affinities. The rauisuchian
top predator Batrachotomus kupferzellensis forms one of the best
studied pseudosuchians, represented by different size classes from
Kupferzell and Vellberg. The following new taxa have been discovered
and identified in the last decade: (1) the enigmatic tetrapod
Colognathus with its characteristic crushing dentition and pointed
snout, (2) jaws of an indeterminate procolophonid, (3) skulls or
skeletons of several small diapsids, among them a tiny protorosaur,
two lepidosauromorphs and a rhynchocephalian, (4) skeletons of new
archosauriforms, among them the armadillo-like doswelliid Jaxtasuchus,
an unarmoured herbivorous taxon with teeth similar to Azendohsaurus, a
small heavily armoured potential insectivore. An armoured species with
bulbous teeth and tear drop-shaped osteoderms probably forms a second,
more basal rauisuchian taxon than Batrachotomus. (5) The recently
described stem turtle Pappochelys rosinae forms the most ancient and
primitive member of the turtle clade.
==


Reinhard Ziegler & Rainer R. Schoch (2015)
11. Synapsiden (Säugerähnliche) im Lettenkeuper. [Synapsids from the
Lettenkeuper]
Palaeodiversity 2015 Special Issue: Der Lettenkeuper - ein Fenster in
die Zeit vor den Dinosauriern: 265-266
http://www.palaeodiversity.org/pdf/08Suppl/11Palaeodiversity_SB_Ziegler.pdf

Synapsids form abundant and diverse assemblages in Triassic deposits
of Gondwana and North America, but in the German Triassic they are
very rare. Despite earlier claims, dicynodonts were not found in the
Lower Keuper, and at present the only recognized group form the
cynodonts, identified on the basis of a single traversodontid tooth
that was referred to the new taxon Nanogomphodon wildi.

===

also


Hans Hagdorn, Rainer Schoch, Dieter Seegis & Ralf Werneburg (2015)
14. Wirbeltierlagerstätten im Lettenkeuper  [Vertebrate Lagerstaetten
in the Lettenkeuper]
Palaeodiversity 2015 Special Issue: Der Lettenkeuper - ein Fenster in
die Zeit vor den Dinosauriern: 325-358
http://www.palaeodiversity.org/pdf/08Suppl/14Palaeodiversity_SB_Hagdorn.pdf



The Lower Keuper in Germany is well known for its extraordinary rich
fossil vertebrate sites which range among the most diverse late
Ladinian limnic to brackish lagerstaetten in the world. This chapter
gives an overview of the 19th century historical sites like the
Gaildorf Vitriolschiefer, which yielded the first “labyrinthodont”
amphibians, the Ceratodus site of Bibersfeld-Rieden, and the Hoheneck
limestone, which became famous for the earliest fi nds of the small
marine sauropterygian Neusticosaurus, and the fossil sites of
Kupferzell, Vellberg, Wolpertshausen, Michelbach, Schwäbisch
Hall-Steinbach, and Kirchberg on River Jagst, which were discovered
and exploited during the last 30 years. All these localities located
in northern Württemberg originated from lacustrine and/or brackish to
restricted marine environments. Lagerstaetten of similar origin and
fossil content were also discovered in Thuringia. From the
sedimentological and palaeontological record of these lagerstaetten,
their changing palaeoenvironments and vertebrate palaeocommunities are
reconstructed. Additionally to these conservation lagerstaetten, the
Lower Keuper is rich in bone beds. These condensation lagerstaetten
are characterized by prefossilized and reworked vertebrate material
from different stratigraphic horizons that were condensed over longer
periods of time. The most famous of these bone beds is the
Muschelkalk-Keuper boundary bone bed that covers thousands of square
kilometers over a low angle disconformity. Besides this “bonanza of
fossil bones”, additional and less well known Lower Keuper bone beds
are described.