Discover The 9 Strangest Theropods

© Daniel Eskridge/

Written by Heather Hall

Updated: October 6, 2022

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Theropods initially arose around 230 million years ago during the Triassic period and split into many lineages. One of the lineages gave rise to the first birds somewhere during the Jurassic period. They lasted until the end of the Cretaceous period, around 65 million years ago, when all non-avian dinosaurs died out.

Theropod dinosaurs walked on two legs. Their forelimbs had a minimal range of motion; their palms faced backward or toward the ground. Although a minority of herbivorous (plant-eating) theropod species evolved throughout the Cretaceous epoch, theropods were generally carnivores (meat-eaters).

The Spinosaurus, Allosaurus, and Tyrannosaurus rex are among the dinosaurs in the Theropod suborder (Saurischia). However, paleontologists have also pointed out some of the strangest ‌theropods in this dinosaur community.

Concavenator corcovatus 

The Concavenator corcovatus (“Hunchback Hunter of Cuenca”) is a theropod genus discovered in September 2010 in Spain.

This theropod from the early Cretaceous period of Europe came with two strange adaptations: 

  • a triangular structure on its lower back, just above the hips, which could have supported a sail or fatty hump;
  • a series of “quill knobs” on its forearms were possibly bony structures that supported small arrays of feathers.

The Concavenator had one or two humps on its back, which are thought to have been used for body heat, communication, and storing body fat. They could reach a length of anywhere between16 inches to 20 feet. 

It was claimed that the hump was so brightly colored that it could be seen from a mile away.  A healthy Concavenator’s hump would be huge, making it a desirable partner and repelling potential rivals and other theropods. 

Concavenator’s forearm feathers were clearly created for display rather than insulation. This may provide insights regarding the evolution of feathered flight in the future.

Concavenator also had feather-like structures on its arms. This is more evidence that most dinosaurs had plumage and feather-like structures and were more closely related to birds than was once thought.

Concavenator corcovatus 

Concavenator was a carnivorous theropod dinosaur that lived in Spain during the Cretaceous Period. It had a strange, triangular hump on its back.



The Kulindadromeus was a feathered dinosaur, an ornithopod, a small, two-legged, plant-eating ornithischian with scaly, lizard-like skin, previously thought to be scaly.

Only carnivorous dinosaurs were previously thought to have had feathers, but this new species suggests that all dinosaurs may have had feathers. 

The fossilized remains of a feathered plant-eating dinosaur that lived between 169 and 144 million years ago in the lake-dotted lowlands of Jurassic Siberia were discovered by Dr. Pascal Godefroit and his colleagues in 2014.

Furthermore, if Kulindadromeus had feathers, it could also have a warm-blooded metabolism, necessitating rewriting a few dinosaur works of literature.

Nothronychus mckinleyi 

A team led by Jim Kirkland and Doug Wolfe discovered a new sort of unusual theropod dinosaur in the Zuni area of New Mexico in 2001. It was given the name Nothronychus Mckinleyi because of its massive, sloth-like claws that reached a length of one foot (0.3 meters).

The Nothronychus looked like the Therizinosaurus and other therizinosaurs. It measured up to 6 meters (20 feet) in length, 3.4 meters (12 feet) in height, and weighed up to one ton. Its small head and long neck allowed it to reach into the treetops and pick out branches. 

The Mckinleyi component of its name was inspired by Bobby McKinley, from whose farm the fossilized remains of this remarkable theropod were found. A few years later a more complete specimen of the Nothronychus was discovered in the Tropic Shale of Utah.

The Nothronychus has long and sharp claws on its arms. Although these claws appeared threatening, they were for grabbing branches and moving them closer for consumption. They would, however, produce potentially lethal weapons if threatened. 

The Nothronychus moved on two thick, powerful rear legs, but it was unlikely to travel quickly. It had a short, stocky tail that most likely helped keep it balanced on its back legs. 

Scientists aren’t sure when it happened, although it’s thought to have happened during the early Cretaceous Period. Because they were herbivores, most scientists assume Nothronychus and other therizinosaurs had downy feathers and potbellies. 

It may sound strange to consider, but Nothronychus and its relatives descended from raptor-like theropods like Velociraptors.

Nothronychus mckinleyi 

The small head and long neck of the Nothronychus allowed it to reach into the treetops and pick out branches. 

© Law

Qianzhousaurus sinensis 

The Qianzhousaurus Sinensis belongs to the same family as Tyrannosaurus rex. It was a tyrannosaurid dinosaur genus that lived during the Late Cretaceous period in Asia. The Qianzhousaurus’ extended snout made it gain the nickname “Pinocchio rex”.

The Qianzhousaurus is a medium-sized tyrannosaurid that looks similar to Albertosaurus and Tyrannosaurus but differs in appearance due to its elongated snout and slender build. 

According to the researchers, the Qianzhousaurus Sinensis was around 9 meters long from snout to tail, with an elongated skull and long teeth, as opposed to a traditional Tyrannosaurus’ deeper, more powerful jaws and thick teeth. It also has spikes running down its neck and chest and a pair of spiky crests above its eyes.

Although the dinosaur coexisted with deep-snouted tyrannosaurs, it was not in direct conflict with them because they hunted different prey. 

To avoid becoming agitated, Qianzhousaurus is a social carnivore who prefers to dwell in small groups. They are, however, a species that can be simply handled if their environmental needs are met. 


The Oryctodromeus was a tiny ornithopod dinosaur whose fossilized bones were discovered around 95 million years ago. It is a member of the small, probably fast-running herbivorous family Hypsilophodontidae. It’s the earliest dinosaur to show evidence of burrowing activity.

The discovery of three Oryctodromeus individuals at the bottom of a two-meter-long, sediment-filled burrow proved certain dinosaurs had adapted to burrowing. Burrowing has various advantages, including better child-raising, more tolerance of climate variations, and a secure haven to flee predators.

The preserved burrow segment has two twists and smaller secondary sandstone cylinders of varying sizes that were likely formed by smaller creatures sharing the burrow (commensal). The burrow closely resembles the adult dinosaur’s proportions, indicating that it was the digger.

The tail of Oryctodromeus might have been more flexible than the tails of other hypsilophodonts. It’s also speculated that it may have dug with its broad horny beak.

Chilesaurus diegosuarezi 

The Chilesaurus diegosuarezi was a little horse-sized dinosaur that lived 145 million years ago. It was named after Diego Suárez, who discovered the first bones in the Toqui Formation in southern Chile.

At least five Chilesaurus individuals were discovered at the site, along with remnants of other dinosaur species such as sauropods. According to the researchers, Chilesaurus was the most prevalent dinosaur in the ecosystem.

They also discovered some bones resemble those of various carnivore groups, while others resemble those of long-necked plant-eating dinosaurs. The evidence points to Chilesaurus being a theropod dinosaur, but its teeth and skull bones show it was a vegetarian, which is exceedingly unusual for the group.

Chilesaurus’ abundance is most likely because of its vegetarian diet, and it likely played the same ecological role as other more common plant-eating dinosaurs worldwide.

Caudipteryx, whose name translates to “tail feather,” were the size of peacocks and lived in the early Cretaceous Period’s Aptian period (about 124.6 million years ago). They had feathers, and their general appearance was surprisingly avian.


The Caudipteryx possessed a short, boxy cranium with a beak-like nose and a few tapering teeth in its upper jaw. It was likely a quick runner because of its long legs and robust trunk.

Like birds and other oviraptorosaurs, Caudipteryx had a short tail that becomes stiffer toward the tip and a few vertebrae. Its primitive pelvis and shoulder, as well as the quadrate, squamosal, and mandibular fenestras of its skull, are all present. 

Also like early birds, it possessed a hand skeleton with a smaller third finger. However, it is believed that Caudipteryx was an omnivore.

The uncinate processes on its teeth and ribs resembled those of birds. Its first toe could have been partially turned inward, and its overall body proportions are similar to those of contemporary flightless birds.


Caudipteryx was an peacock-sized omniviourous theropod that lived in China during the Cretaceous Period.



One of the weirdest fossils finds ever made is the Microraptor. It’s the tiniest dinosaur in the dinosaur bestiary and a tiny, feathered dinosaur with four rather than two wings.

In the third episode of the television series Prehistoric Park, the Microraptor took center stage. They were depicted as gliding, closely linked dinosaurs to birds. They descended to feast on worms and other creatures that the tracks of Titanosaurus had brought to the surface.

Spinosaurus aegyptiacus

The Spinosaurus was perhaps the strangest theropod dinosaur. It had a body mass of four tons and could reach heights of up to 49 feet. Its teeth were straight conical shapes without serrations, and its skull resembled that of a modern crocodile‘s. 

The Spinosaurus’s tall neural spines, some of which grew to at least 5.4 feet ‌and formed a distinctive sail-like structure on its back, were its most striking characteristic. Its colossal tail fin and peculiar center of gravity enabled it to swim better than any other giant theropod dinosaur.

Fish was a significant part of Spinosaurus’ diet, although it was not its exclusive food source. The way it hunted is thought to have been similar to that of a modern heron or stork, stepping into the water and submerging a portion of its head to catch prey. Additionally, it likely scavenged for terrestrial species on land.

Spinosaurus aegyptiacus



While these are a few of the strangest theropods, there are lots more to read about. It’s vital to note that more theropods are being discovered all the time. 

Up next; Here are some other carnivorous dinosaurs you might want to read up on:

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About the Author

Heather Hall is a writer at A-Z Animals, where her primary focus is on plants and animals. Heather has been writing and editing since 2012 and holds a Bachelor of Science in Horticulture. As a resident of the Pacific Northwest, Heather enjoys hiking, gardening, and trail running through the mountains with her dogs.

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