I found some on the edge of the snow biome west side next to the place with the never ending war but be careful there are allos, rexes, raptors, scorpions, carnos, argies and sometimes a sarco but if you have a flying mount you’ll be right
They spawn very rare on the map but are mostly seen near the volcano. If u have a argentavis just pick them up and throw them in some trap his all yours after that (can be picked by argentavis in mobile)
They spawn on mountains, and you have to pick them up from danger because taming them at the mountain is very risky and dangerous! I just picked one up, brought it to the gate of my base and knocked it lit with toxic arrows.