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Mosasaurs from Germany + Prognathodon from Netherlands



Ben Creisler
bcreisler@gmail.com


Two recent online papers not yet mentioned:

Sven Sachs, Jahn J. Hornung and Mike Reich (2014)
Mosasaurs from Germany – a brief history of the first 100 years of research.
Netherlands Journal of Geosciences  (advance online publication)
DOI: http://dx.doi.org/10.1017/njg.2014.16
http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9306137&fulltextType=RA&fileId=S001677461400016X



In Germany, mosasaur remains are very rare and only incompletely
known. However, the earliest records date back to the 1830s, when
tooth crowns were found in the chalk of the Isle of Rügen. A number of
prominent figures in German palaeontology and geosciences of the 19th
and 20th centuries focused on these remains, including, among others,
Friedrich von Hagenow, Hermann von Meyer, Andreas Wagner, Hanns Bruno
Geinitz and Josef Pompeckj. Most of these works were only short notes,
given the scant material. However, the discovery of fragmentary
cranial remains in Westphalia in 1908 led to a more comprehensive
discussion, which is also of historical importance, as it illustrates
the discussions on the highly controversial and radical universal
phylogenetic theory proposed by Gustav Steinmann in 1908. This theory
saw the existence of continuous lines of descent, evolving in
parallel, and did not regard higher taxonomic units as monophyletic
groups but as intermediate paraphyletic stages of evolution. In this
idea, nearly all fossil taxa form part of these lineages, which extend
into the present time, and natural extinction occurs very rarely, if
ever. In Steinmann's concept, mosasaurs were not closely related to
squamates but formed an intermediate member in a anagenetic chain from
Triassic thalattosaurs to extant baleen whales. The newly found
specimen led Josef Pompeckj to write a vehement rebuttal to
Steinmann's theory, published in 1910, showing that his conclusions
were conjectural and speculative, being based on convergence and not
supported by scientific evidence. This particular specimen, housed in
Göttingen, later also inspired a piece of palaeoart by Franz Roubal
under the instructions of Othenio Abel.

With the exception of a vertebra from the Campanian of former East
Prussia (now Russian Federation), and a possible vertebra from the
Cenomanian of Dresden, Saxony, all datable material – today partly
lost – originated from the northern part of present-day Germany and
stratigraphically from the Campanian–Maastrichtian. The purported
record from the Cenomanian of Bavaria (southeastern Germany) was most
probably an error, based on Upper Jurassic crocodilian material.

****
A.S. Schulp and J.W.M. Jagt (2014)
New material of Prognathodon (Squamata, Mosasauridae) from the type
Maastrichtian of the Netherlands.
Netherlands Journal of Geosciences  (advance online publication)
DOI: http://dx.doi.org/10.1017/njg.2014.15
http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9305890&fulltextType=RA&fileId=S0016774614000158

A partial quadrate, here assigned to the globidensine mosasaur
Prognathodon cf. saturator, is recorded from the basal Valkenburg
Member (Maastricht Formation) in the type area of the Maastrichtian
Stage (southeast Netherlands, northeast Belgium). Occurrences of
Prognathodon saturator in this area are extremely rare, which might
well be linked to the offshore habitat preferred by this species.