[Endoperez]

Saber Cherry, an vibrant character no longer regular here, once suggested a nation of animals and/or vinemen. Her ideas were strange, but the ideas I remember being thrown about were:

vinemen, vine ogres and their recruitable versions with some simple equipment

aquatic 'killer whale' national summon, and killer tuna and other strange stuff

Any way, some animals that you might've missed:
great cat (second form of some Yomi/Shinuyama sorceress (uba?) summon, you can use the sprite at least)
horned serpent/sacred serpent of C'tis
demon toads of Mictlan (or non-demon versions of them)
Markata of the monkey nations, and perhaps atavi and/or bandar as well
tigers (the ones Tiger Riders of MA Bandar Log leave behind in battles)
Griffons and those lizards the Garnet and Jade Amazons ride
Black Hunters of MA Machaka also have second forms with just the animal
perhaps the serpents the Sauromatians/Pythians ride
Hydras/hydra hatchlings
the wolf form of Jotun Skratti (a size 4 giant wolf, bigger than the dire wolves)
Great Bears, the EA Ulm summon
Kithaironic Lions, cave/fire/frost drakes, wyverns (unless you intend them to remain summons)
Jaguars of Mictlan (I think they have a national Conjuration for those, but I might've confused something with their Rain of Jaguars spell)
great eagles who lead the black hawks of Call of the Winds

also, the carrion creatures reanimated by Pangaea are most often animals, and include undead moss-elephants

basilisk, cockatrice and other rare creatures from crossbreeding

phoenix could be used, perhaps for a hero