Therizinosaurus

Therizinosaurus (/θɛˌrɪzɨnɵˈsɔrəs/; 'scythe lizard', from the Greek therizo meaning 'to reap' or 'to cut off' and sauros meaning 'lizard') is a genus of very large theropod dinosaurs.

Facts
Therizinosaurus comprises the single species T. cheloniformis, which lived in the late Cretaceous Period (late Campanian-early Maastrichtian stages, around 70 million years ago), and was one of the last and largest representatives of its unique group, the Therizinosauria. Fossils of this species were first discovered in Mongolia and were originally thought to belong to a turtle-like reptile (hence the species name, T. cheloniformis — "turtle-formed"). It is known only from a few bones, including gigantic hand claws, from which it gets its name.

Description
Therizinosaurus belonged to the therizinosaur branch of the theropod family, and like the rest of them, it possessed long arms with elongated claws, similar to the Cenozoic mammals chalicotheres and giant ground sloths to better reach branches and small heads on long necks to better reach branches and vegetation, thus reversing the usual theropod theme of large heads on small necks.

Feathers
Like many theropod dinosaurs, Therizinosaurus may have been theoretically feathered, but Chased by Dinosaurs (2003) has shown it to be featherless instead. Indeed, the second episode of CBD, The Giant Claw, was centered on the Therizinosaurus, as Nigel Marvin theoretized as to what sort of creature it could be.

The Giant Claw
The second episode of CBD, The Giant Claw, was centered on the Therizinosaurus, as Nigel Marvin theoretized as to what sort of creature it could be. Furthermore, this episode revealed that when first the giant titular claws of Therizinosaurus were discovered they were thought to be ribs of a giant tortoise; there was demonstrations of Therizinosaurus' eggs, embryo, arm bones and dung - the latter especially important because it showed that Therizinosaurus was a plant-eater unlike its distant cousins Velociraptor, Monoykus and especially Tarbosaurus. Regardless, a Therizinosaurus was able to stand its ground against a Tarbosaurus during a confrontation at a watering hole which ended with the Tarbosaurus retreating.

At the end of The Giant Claw the rest of the therizinosaur family joined their leader at the watering hole, revealing that they were plant-eaters rather than carnivores as Nigel had theoretized at the beginning of the episode.