Dododex

ARK: Survival Evolved & Ascended Companion

List of the longest names I've found (post modding):

I am also excluding creatures with 2 words (I.e Terror Bird) as I find it cheating, Rex shall be named in full, not in abbreviated form, as well as Quetzal

Carcharodontosaurus

Gigantopithecus

Therizinosaurus

Giganotosaurus

Chalicotherium

Tyrannosaurus

Quetzalcoatlus

Megapithecus

Mesopithecus

Brontosaurus

Megapirhana

Megatherium

Dinopithecus

Lystrosaurus

Stegosaurus

Pteranodon

Coelacanth

Sabertooth

Tapejara