I think that Dimetrodon is probably not coming because I'm pretty sure on the Discord they said that there's only going to be one Permian species coming to the game and it's like, 96% going to be Diictodon in Update 16 I think

Nah, I think it will be these species to appear in Update 19:

Carnivore I = Carnotaurus sastrei

Carnivore II = Utahraptor ostrommaysi

Carnivore III = Kelenken guillermoi

Herbivore I = Edmontonia rugosidens (with Denversaurus schlessmani)

Herbivore II = Megatherium americanum

Herbivore III = Doedicurus clavicaudatus

Herbivore IV = Diplodocus carnegii (with Seismosaurus hallorum)

Herbivore V = Macrauchenia patachonica

Herbivore VI = Diictodon feliceps

Herbivore VII = Therizinosaurus cheloniformis

Insectivore I = Mononykus olecranus

Insectivore II = Peltephilus ferox

According to the leaks, It sort of likely that we think that the Diictodon, Mononychus, and Peltephilus are gonna be added in update 16, during introduction of the terrariums (the revamp of the mini exhibits).

But what about the dodo bird and the quagga, and the dire wolf??