That's blue, bright, shiney blue, and that's not the fur, that's his skin. Where's the brownish tint? Where's the vital reason for it to be blue too, by the way? Don't know the name in English, it's a mandrille in French, if you wana look it up (though I guess you already know about it, it's nothing new or rare).
As for beastmen, when people say beastmen, they usually refer to Gors, which are clearly a stable species of their own just like skavens now.