- « The thin, lime coloured crest on it´s head opening and closing like a Chinese fan, his long green body swaying from side to side as his transparent wings stuck firmely on his sides. »
- — Description[src]
|Time period :||Late Permian peroid|
|Creature type :||Gliding reptile|
|In the series|
|Appearances :||See full list below|
Coelurosauravus are lizard-like diapsid reptiles native to the Permian period and resembling small green iguanas or other modern day lizards. It has specialized wing-like structures allowing it to glide. These were rod like structures with skin stretched over them; this features is unique to this genus. The average length of the specimens were 60 cm and the body was long and flat, suitable for its gliding nature.
A Coelurosauravus came through an Anomaly to the Forest of Dean in the present day, where it was found by Ben Trent, who mistook it for Draco volans, and named Rex. Ben reported his discovery of Rex to Wellington Zoo, and Abby Maitland eventually came to see Rex. When Abby realised that Rex wasn't Draco volans, she and Ben returned to the forest with him. Rex and Abby were separated from Ben, and became lost in the forest.
When Ben looked through the Forest of Dean Anomaly into a hill range in the Permian, he saw a group of Coelurosauravus flying nearby in the hills. Abby and Rex eventually came across a Scutosaurus while trying to find Ben, and met the Home Office team. The following morning, Rex was taken back to the Home Office and examined by scientists there, until he escaped from the lab and into the building using his gliding ability. When Rex reaches a window, he initially flies out through it but almost immediately returns to Abby.Nick Cutter subsequently took Rex with him into the Permian through the Forest of Dean Anomaly to return Rex to his home time. However, after approximately two hours, Rex returned to the present through the Anomaly, and the Anomaly then closed. Before any of the rest of the Home Office team noticed Rex, Abby apparently took and hid him from them.
Abby secretly took Rex back to her flat and kept him as a pet. Rex was also kept most of the time in a glass case, and his return to the present became known to Connor Temple as well when he moved into Abby's flat.
When Connor accidentally left a window in Abby's flat open when leaving, Rex flew out through the window, and into Connor's car without him noticing. As a result, Connor unknowingly took Rex with him in his car to a new Anomaly site at Wimbledon Golf Course. When Connor finally noticed Rex, the latter left the car and escaped into the woods.Connor followed Rex, and the two were attacked and chased on the golf course by a Pteranodon. Though they managed to escape the Pteranodon, Rex ran off again. Abby and Connor eventually found Rex in the woods cowering from a swarm of Anurognathus roosting in the nearby trees, and Rex was returned to Abby's flat after the Anomaly incursion was dealt with.
When Rex first met Caroline Steel, he took an instant disliking to her.
Caroline shut Rex in the flat's freezer while she was alone at Abby's flat with him. Abby eventually found Rex in the freezer, and she and Connor managed to warm him up and recuperate him.
After Connor broke up with Caroline by text, Caroline lured Rex out with a bowl of fruit and then attacked him with a tennis racquet. Caroline was ultimately able to use the bat to knock Rex out, and stole him.
Abby got Rex to wake Connor up by eating vegetables off of his face.
Tony put Rex on eBay, but Connor was able to get Rex back from Tony and return him to Abby's flat with Hilary Becker's help.Anomaly detector, Rex appeared to scold him for it before he left to investigate an Anomaly signal.
After Connor and Abby disappeared on a mission into the Future, Rex was kept in the ARC's Menagerie with a Columbian Mammoth after the ARC was revived. After Abby and Connor returned to the present, Abby happily reunited with Rex at the Menagerie.
Rex escaped the Menagerie into a lab in the ARC, and accidentally triggered the ARC's new security system when the system scanned him. Rex was then locked in the lab with Philip Burton when the ARC went into lockdown, and the two slowly started to suffocate as the system began to suck the air from the room. After Connor managed to undo the lockdown, he found that Rex had suffocated, but managed to revive him.
When a swarm of Future Beetles invaded the ARC and the building went into lockdown, Abby brought Rex to a secure lab from the Menagerie and left him safe inside. However, Rex escaped the lab and into the ARC's car park when the Beetles chewed through the lab's walls. Abby eventually managed to get Rex to come to her, and she kept him safe in the ARC's panic room while a gamma ray from the First Man-made Anomaly killed all the Future Beetles in the ARC.
- Coelurosauravus is the first creature to be given a name, and one of the few creatures to actually be given one.
- This is the only creature to appear in all five series of the original Primeval show.
- As the series continues Rex's wings become more dragon/bat like, starting as rounded sails and then progressing into folding wings similar to a bat's.
- Real Coelurosauravus were only capable of gliding, but the ones in the show have powered, flapping flight.
- The crest on Coelurosauravus' heads is speculative, and they aren't depicted with the distinctive bony frill that the real ones had.
- It is depicted as being much larger than the real animal, which was only about as long as a human hand.
- Rex seems to be far more intelligent and active than a primitive reptile would probably have been. However, Rex could just be an unusual specimen.
- Rex is often shown being fed plant and fruit matter, but Coelurosauravus was probably an insectivore.
- Episode 1.1
- Episode 1.2
- Episode 1.4
- Episode 1.5
- Episode 1.6
- Episode 2.2
- Episode 2.4
- Episode 2.5
- Episode 2.6
- Episode 2.7
- Episode 3.1
- Episode 3.6
- Episode 3.7
- Episode 3.8
- Episode 3.9
- Episode 4.2
- Episode 4.3
- Episode 4.4
- Episode 5.4