The rhinarium is present in mammals such as the cat.
Howler monkeys are examples of haplorrhines, which have simple nostrils and a dry upper lip instead of a wet rhinarium.
Dogs have rhinarium as well.
The rhinarium is the wet, naked surface around the nostrils of the nose in most mammals. Colloquially it might be called a "wet snout".
Primates are phylogenetically divided into Strepsirrhini ("curly-nosed" primates with rhinariums, which is the ancestral condition) and Haplorrhini ("simple-nosed" primates which have replaced the rhinarium with a more mobile, continuous, dry upper lip).
Mammals with rhinariums tend to have a stronger sense of olfaction, and the loss of the rhinarium in the haplorrhine primates is related to their decreased reliance on olfaction, being associated with other derived characteristics such as a reduced number of turbinates.
Note that the traditional paraphyletic "prosimian" division of primates cannot be characterised by the presence of a rhinarium, due to its absence in the tarsiers, and loss of the rhinarium is not a synapomorphy of the simians or anthropoids, but a symplesiomorphy shared with the tarsier outgroup.
References
Fleagle, J. G. (1988). Primate adaptation and evolution. San Diego: Academic Press.
