Machimosaurus (Crocodylomorpha, Thalattosuchia) revised (free pdf)

[Ben Creisler <bcreisler@gmail.com>]

Ben Creisler
bcreisler@gmail.com

Octávio Mateus, José Ignacio Ruiz-Omeñaca, Philipe Havlik, Yves
Lepage, Marco Brandalise De Andrade (2014)
Revision of the Late Jurassic teleosaurid genus Machimosaurus
(Crocodylomorpha, Thalattosuchia).
Royal Society Open Science 1(2): 140222
DOI: 10.1098/rsos.140222
http://rsos.royalsocietypublishing.org/content/1/2/140222

Machimosaurus was a large-bodied genus of teleosaurid crocodylomorph,
considered to have been durophagous/chelonivorous, and which
frequented coastal marine/estuarine ecosystems during the Late
Jurassic. Here, we revise the genus based on previously described
specimens and revise the species within this genus. We conclude that
there were three European Machimosaurus species and another taxon in
Ethiopia. This conclusion is based on numerous lines of evidence:
craniomandibular, dental and postcranial morphologies; differences in
estimated total body length; geological age; geographical
distribution; and hypothetical lifestyle. We re-diagnose the type
species Machimosaurus hugii and limit referred specimens to only those
from Upper Kimmeridgian–Lower Tithonian of Switzerland, Portugal and
Spain. We also re-diagnose Machimosaurus mosae, demonstrate that it is
an available name and restrict the species to the uppermost
Kimmeridgian–lowermost Tithonian of northeastern France. We
re-diagnose and validate the species Machimosaurus nowackianus from
Harrar, Ethiopia. Finally, we establish a new species, Machimosaurus
buffetauti, for the Lower Kimmeridgian specimens of France and Germany
(and possibly England and Poland). We hypothesize that Machimosaurus
may have been analogous to the Pliocene–Holocene genus Crocodylus in
having one large-bodied taxon suited to traversing marine barriers and
additional, geographically limited taxa across its range.