Name: Aerosteon
(Air bone).
Phonetic: Air-oh-stee-on.
Named By: P. C. Sereno, R. N. Martinez, J. A.
Wilson, D. J. Varricchio, O. A. Alcober & H. C. E. Larsson -
2009.
Classification: Chordata, Reptilia, Dinosauria,
Saurischia, Theropoda, Megaraptora.
Species: A. riocoloradensis (type).
Diet: Carnivore.
Size: Estimated between 7.5 and 9 meters long.
Known locations: Argentina - Anacleto Formation.
Time period: Santonian of the Cretaceous.
Fossil representation: Partial cranium and partial
post cranial remains including right pubis, furcula, gastralia, dorsal
and cervical ribs, ilium, scapulocoracoid and cervical, dorsal sacral
vertebra.
Aerosteon
was a member of Megaraptora,
a group of lightly built theropod dinosaurs that
are notable for having enlarged claws upon their hands. The name of
this group is derived from the misidentification of first member of the
group, Megaraptor
being misdentified as a dromaeosaurid ‘raptor’ based
upon the presence of a single large claw. however new discoveries
including Australovenator
allowed for correct idenitfication as well as
the establishment of a new group.
Aerosteon
is very special both amongst this group and large theropods in general
because ot the air filled spaces (a process called pneumatisation)
within its bones. Not only would this have made the bones bery light
weight but it may have supported an avian type respiratory system
similar to what we see in birds today. Aside from being more support
for the descendency of birds from dinosaurs, this would have allowed a
greater amont of airflow to and from Aerosteon’s
lungs. Speculated to
originally been an aid in temperature regulation, it would have allowed
a faster rate of respiration with may infer a very active predatory
lifestyle for Aerosteon.
Further reading
-Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur
from Argentina - In Kemp, Tom. PLoS ONE 3 (9): e3303 - P. C. Sereno, R.
N. Martinez, J. A. Wilson, D. J. Varricchio, O. A. Alcober & H.
C.
E. Larsson - 2009.
- A new clade of archaic large-bodied predatory dinosaurs (Theropoda:
Allosauroidea) that survived to the latest Mesozoic -
Naturwissenschaften 97 (1): 71–78 - R. B. J. Benson, M. T. Carrano
& S. L. Brusatte - 2010.