Alioramus

Name Meaing: Different Branch

Specimen Name: “Footstabber”

Geologic Era: Late Cretaceous

Location Found: Nemegt Formation, Mongolia (specimen is a cast)

Estimated Range: Modern China/Mongolia

Size: Roughly 5 meters long (adults were probably larger)

Extinction: 70 million years ago

If a specimen in this museum has a unique name, it is probably because that specimen has caused actual physical damage to me. In this case, the claw cast seen below has been rammed into top of my bare foot by none other than the Assistant Curator. Mercifully, the cast lacks the keratin sheath the claw possessed in life, or I would have been looking at a puncture wound instead of a wicked bruise. Two lessons were learned that day…keep all specimens out of reach of the Assistant Curator, and don’t turn my back on that kid for more than a millisecond.

Alioramus would have filled the niche of mid-level predator in its ecosystem. Though specimens indictate a size of roughly 5-6 meters in length, these specimens are from either juveniles of subadults, and do not reflect the true size of a full grown animal. It did share an environment with Tarbosaurus, which approached the size of Tyrannosaurus rex. Very likely, an adult Alioramus would have been a good bit smaller than a full grown Tarbosaurus, though the subadults and juveniles of each species may have borne a superficial resemblance to each other. Alioramus did have decorative crests on its skull, which could have served the purpose of differentiating it from a young Tarbosaurus.

Prey for Alioramus could have included a wide variety of animals found in the Nemegt formation. This variety included oviraptorids, dromaeosaurs, hadrosaurs, and ornithomimids. Alioramus would probably not have gone after a full grown titanosaur, but may have been willing to target weaker individuals. Given the rich environment that was Mongolia roughly 70 million years ago, it should come as no surprise that the fauna was as diverse as it was. 

This is quite the contrast to the Mongolia of the present, which is composed of primarily desert. A comparable faunal complement in the United States would be the Hell Creek formation, which had a similar spread of animals. When first disovered, it was thought that Alioramus was a juvenile Tarbosaurus (like Nanotyrannus is a juvenile Tyrannosaurus), but the crest detailing and larger number of teeth in Alioramus discount this idea.

Image Credits:

Skeleton: By Texas A&M University-Commerce Marketing Communications Photography – 14365- dinosaur 4155, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=34948003

Life Restoration: By Fred Wierum – Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=44522792