Beastman Race?

Anyone else notice that the opponent named "Sidewinder" in the Arena Challenges is of the "Beastman" race? Wonder what that is...

There are gladiators that are more "exotic". I guess they are rare. I don't think Beastman is a race but a group of human(oid) races, all having some kind of and animal characteristics. Sidewinder looks like a naga.
There are also gladiators with unknown race. For example Styx (if I remember correctly).