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Mosasaur papers



From: Ben Creisler
bcreisler@gmail.com


A number of recent (and not so recent) mosasaur papers not yet
mentioned on the DML:


F.M. Holwerda, B.L. Beatty & A.S. Schulp (2013)
Dental macro- and microwear in Carinodens belgicus, a small mosasaur
from the type Maastrichtian.
Netherlands Journal of Geosciences 92 (4): 267-274
http://www.njgonline.nl/publish/articles/000535/english.html

Teeth of the small durophagous mosasaur Carinodens belgicus are known
from Maastrichtian Atlantic-Tethyan deposits worldwide. The peculiar
dentition of Carinodens inspired debate and speculation on its dietary
niche ever since its first description. In this contribution, we
describe the macro- and microwear pattern in five well-preserved
isolated teeth, allowing further and independent evaluation of aspects
of feeding behavior and diet. Macroscopically, wear is concentrated on
the apex and mesiodistal sides. Microwear was mapped using Scanning
Electron Microscopy at several magnifications and can be characterised
as scratches and pits. Coarse scratches were found to be the most
common and pits were found to be the least common feature. Scratch
orientation is primarily along the mesiodistal plane or in the
labiolingual plane with an angle of ~130°. These microwear features
can be explained either by oral processing or passive abrasion by
sediments or food. As scratch width only indicates the minimum width
of the abrading particle, the material causing the wear here could
have ranged from silica-based silts to larger abrasives. However, in
this case, abrasion by sediments might not explain this wear because
of the biocalcarenitic nature of the type Maastrichtian sediments;
siliciclastics are virtually absent. Therefore it is more likely that
hard food particles, such as benthic organisms with hard exoskeletons,
caused the wear on the enamel of Carinodens, or Carinodens ventured
out to more sandy areas to forage as well. The mesiodistal and
labiolingual direction of the microwear scratches might suggest that
Carinodens showed more complexity in the use of its teeth than simple
grasping, and that a gripping and pulling motion during feeding
similar to that employed by modern varanids may have been the cause.

===


A.S. Schulp, M.J. Polcyn, O. Mateus & L.L. Jacobs (2013)
Two rare mosasaurs from the Maastrichtian of Angola and the Netherlands.
Netherlands Journal of Geosciences 92 (1): 3-10
http://www.njgonline.nl/publish/articles/000510/english.html


We report here the addition of two rare mosasaur taxa to the
Maastrichtian marine amniote fauna of Angola, both of which are also
found in northern Europe. The new specimens include a dentary fragment
referable to the large carnivore Prognathodon cf. saturator and an
isolated tooth of the small durophage Carinodens belgicus. Both were
recovered from Maastrichtian outcrops in southern Angola in 2011.
Additionally, a complete posterior mandibular unit of a large mosasaur
from the type Maastrichtian of the Netherlands, collected some time
prior to 1879 and previously identified as ‘Mosasaurus giganteus’, is
described and reassigned here to Prognathodon saturator; historical
issues surrounding the taxonomic attribution of this specimen are
clarified. The new material extends the known geographic distribution
of Prognathodon saturator and Carinodens belgicus.

==

E.W.A. Mulder, P. Formanoy, W.B. Gallagher, J.W.M. Jagt & A.S. Schulp (2013)
The first North American record of Carinodens belgicus (Squamata,
Mosasauridae) and correlation with the youngest in situ examples from
the Maastrichtian type area: palaeoecological implications.
Netherlands Journal of Geosciences 92(2/3): 145-152
http://www.njgonline.nl/publish/articles/000524/english.html


Four recently collected tooth crowns of the rare latest Cretaceous
(late Maastrichtian) durophagous mosasaur Carinodens belgicus are
discussed; the first record from the Atlantic coast of North America
(Maryland), and three additional in situ examples from the
Maastrichtian type area in the southeast Netherlands and northeast
Belgium. Also presented are an updated overview of the material
recorded to date, and a discussion of the palaeobiogeographical and
palaeoenvironmental distribution of the genus. Towards the end of the
Cretaceous, Carinodens appears to have been successful in exploiting
the margins of both the proto-Atlantic Ocean and the Tethyan Realm.

==

A.S. Schulp, H.B. Vonhof, J.H.J.L. van der Lubbe, R. Janssen & R.R.
van Baal (2013)
On diving and diet: resource partitioning in type-Maastrichtian mosasaurs.
Netherlands Journal of Geosciences 92 (2/3): 165-170
http://www.njgonline.nl/publish/articles/000527/english.html

The carbon isotope composition of tooth enamel from all five mosasaur
taxa known to date from the type Maastrichtian (southeast
Netherlands,northeast Belgium) has been analysed. Differences in
enamel δ13C values between taxa suggest resource partitioning. Body
size and δ13C value correlate surprisingly well, with larger taxa
having δ13C values more depleted in the heavier 13C isotope.