Name:
Teratosaurus
(Monster lizard).
Phonetic: Teh-rat-o-sore-us.
Named By: Christian von Meyer - 1861.
Classification: Chordata, Sauropsida,
Archosauromorpha, Rauisuchidae.
Species: T. suevicus.
Diet: Carnivore.
Size: Uncertain due to lack of remains.
Known locations: Germany.
Time period: Norian of the Triassic.
Fossil representation: Partial right maxilla
(tooth bearing bone of the upper jaw) with teeth.
Teratosaurus was among the first rauisuchians to ever be named, though in the early days of the genus classification, it was actually thought to be a dinosaur. The holotype specimen of Teratosaurus, a partial right maxilla with teeth, was first found near Stuttgart, Germany in the year 1860. The holotype found its way to the famous Christian von Meyer who initially considered a kind of phytosaur called Belodon, but soon found the new maxilla to be quite different. Von Meyer created a new genus called Teratosaurus for the specimen, though oddly described the maxilla as the left and not the right.
Post
cranial skeletal remains were soon added to the maxilla holotype, but
this was when things got really messed up. The post cranial remains
were of sauropodomorph
dinosaurs, the early precursors to the later
sauropod
dinosaurs. For over a century Teratosaurus was
identified as
either a carnivorous sauropodomorph dinosaur or an early theropod since
the teeth of the original maxilla were clearly those of a meat eater,
not a plant eater. The truth of the matter was not discovered until
1985 when Peter Galton wrote the first paper re-describing the
holotype maxilla. The result of this is that the sauropodomorph
remains once attributed to the Teratosaurus genus
as additional species
have now been moved to new genera including Efraasia.
On an unrelated
note after this a new species named T. silesiacus
was created on the
description of a new maxilla in 2005, though this was subsequently
moved to its own new genus, Polonosuchus
in 2009.
The
true size of Teratosaurus is currently unknown.
Previous estimates
have suggested a total length of anywhere between three and six meters
long, and while these length are within the known scope of
rauisuchian sizes, many of these estimates date from times when
sauropodomorph remains were attributed to the genus. Since these
sauropodomorph remains are no longer included with the Teratosaurus
genus, older size estimates can no longer be valid. As such with
only a right maxilla attributed to the genus, only a best guess can
be offered in determining the size of Teratosaurus.
Although
the size is not known for certain, the maxilla of Teratosaurus
does
indicate that the genus was not small, and rauisuchians were amongst
the top predators of the late Triassic. Teratosaurus
would be
expected to have been quadrupedal with a similar body form to other
rauisuchians, with a tough armoured back. Though mostly
quadrupedal, it may have been capable of rearing up on its hind
legs, perhaps to get a better vantage when attacking. This is of
course all speculation based upon a supposed similarity with relative
genera.
Teratosaurus
also should not be confused with the similarly named Teratophoneus,
a
type of tyrannosaur
that lived in North America during the late
Cretaceous.
Further reading
- Reptilien aus dem Stubensandstein des oberen Keupers -
Palaeontographica 7: 253-346 - H. von Meyer - 1861.
- The poposaurid thecodontian Teratosaurus suevicus
von Meyer, plus
referred specimens mostly based on prosauropod dinosaurs -
Stuttgarter Beitr�ge zur Naturkunde, B, 116: 1-29. - Peter
M. Galton - 1985.
- The Late Triassic Reptile Teratosaurus, A
Rauisuchian not a
Dinosaur - Palaeontology 29: 293-301. - Michael J.
Benton - 1986.
- A new rauisuchian reptile (Diapsida: Archosauria) from the
Late Triassic of Poland - Journal of Vertebrate Paleontology,
25(1):78-86. - T. Sulej - 2005.
- The taxonomy and anatomy of rauisuchian archosaurs from the Late
Triassic of Germany and Poland - Acta Palaeontologica Polonica
54 (2): 221–230 - Stephen L. Brusatte, Richard J.
Butler, Tomasz Sulej & Grzegorz Niedźwiedzki - 2009.