@Jakub - despite what you were told, this is actually a Mona Monkey (C. mona). I've just been looking at some photos and video of the Dubai animals and they all show Mona Monkeys (the only photo on Zoochat previously - by @devilfish - didn't show the animals in the right position for a good identification). A couple of prominent pointers are that only Mona Monkeys have the white patches at the base of the tail (none of the other species in the mona group have these), and in Mona Monkeys both arms and legs are black on the outer side (in Dent's Monkeys the arms are black but the legs are brown).
