male
Carl was a brontotherium that lived during the days of the ice age with another brontotherium named Frank. He is a minor antagonist in Ice Age.
Carl (Ice Age)
Rhinoceros
for Rhinoceros in Fictional animals by species
Suggested by manassestobias
Obviously, don't nominate any human characters. Hybrids like Cheetah or The Lizard are okay, as are shapeshifters with one set animal form (eg Professor McGonagall.)