Coelurus

“Hollow tail”

Coelurus is a poorly known genus.

From most of the skeleton of a single individual, the appearance of Coelurus can be reconstructed quite well. Numerous vertebrae, some pelvic and shoulder girdles as well as most of the arms and legs are present.

To date, only one species is recognized as valid: the type species, C. fragilis. It was described by Othniel Charles Marsh in 1879. He was impressed by the hollow insides of the thin-walled vertebrae and gave it the name: Coelurus fragilis.

Coelurus means something like “hollow tail”. 

Coelurus fragilis means “delicate hollow tail”.

Coelurus had a relatively long neck and torso. He had very long vertebral bodies, which is used to reconstruct his body structure. 

It had a long metatarsal bone, which leads to the assumption that its hind leg was also long and slender. The thigh bone (femur) was 55 cm long. It may have had a small, slender skull. Unfortunately, no skull has been found yet.

Coelurus was not a large dinosaur.

Its weight was estimated at around 13 to 20 kilograms, with a length of around 2.4 meters and a waist height of 0.7 meters.

Coelurus fragilis was the size of an average adult human.

It was a small terrestrial predator that fed on small prey such as insects, mammals and lizards. It is believed to have been a fast animal.

Image sources: Nobu Tamura (http://spinops.blogspot.com), CC BY 3.0 https://creativecommons.org/licenses/by/3.0, via Wikimedia Commons

Jaime A. Headden (User:Qilong), CC BY 3.0 https://creativecommons.org/licenses/by/3.0, via Wikimedia Commons

FanCollector; original artwork by User:ArthurWeasley, CC BY 3.0 https://creativecommons.org/licenses/by/3.0, via Wikimedia Commons