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smaller but similar to
Camotaurus?
To decide, we would have to trans-
port the skeleton back to the lab and clean up the bones because the
last and most crucial piece of evidence needed to establish its identity,
the skull, was still missing. The few fragments of skull bones that we
had uncovered were quite troubling because they suggested that the
skull might have been destroyed. But perhaps the skull had just bro-
ken away from the rest of the body and was buried nearby in the hill-
side.
Because we had been unable to locate the skull, we had decided to
take a large block of mudstone from the area where the skull could
have been buried, hoping to find it inside when the block was prepared
at the museum. Although our hopes were not too high, a couple of
months after we returned home, Rodolfo called with great news. His
chief preparator, Sergio Saldivia, had found most of the skull in the
block. At least one side of it was fairly complete, which would allow us
to make more concrete comparisons with other abelisaur skulls and
determine its identity.
When the skeleton was fairly clean, Luis and Rodolfo started com-
paring it to other abelisaurs. Abelisaurs are primitive carnivorous
dinosaurs known primarily from the late Cretaceous of the Southern
Hemisphere. Most species, as well as the best-preserved specimens, of
this theropod family come from Patagonia, including
Camotaurus,
Abelisaurus,
and
llokelesia,
but abelisaurs are also known from the
late Cretaceous of India and Madagascar. Fragmentary remains have
been reported from Western Europe, but these are poorly preserved
and inconclusively identified.
Although the shapes of its bones showed that our predator from
Auca Mahuevo was closely related to
Camotaurus,
it was distinctly dif-
ferent from that species. Compared to the skull of
Camotaurus,
our
skull was proportionally longer but not as tall. In addition,
Camotaurus
has large, prominent horns on the skull above the eyes, whereas the
Auca Mahuevo abelisaur had only small bumps. As mentioned earlier,
the arms of the Auca Mahuevo abelisaur were proportionately longer
than those of
Camotaurus,
although they were still quite short and
reduced in relation to those of most other meat-eating dinosaurs. The
bones of this skeleton were superbly preserved, but our biggest surprise
was finding small, fossilized casts and impressions of the predator's
muscles preserved above the hips in the mudstone that surrounded
