Colobinae

The Colobinae are a subfamily of Old World monkeys. The family includes 61 species in 11 genera, including the "Colobus" monkeys, the large-nosed proboscis monkey, and the grey langurs.
Some classifications split the colobine monkeys into two tribes, while others split them into three groups. Both classifications put the three African genera "Colobus", "Piliocolobus", and "Procolobus" in one group; these genera are distinct because they have stub thumbs (Greek κολοβός "kolobós" = "docked").
The various Asian genera are placed into one or two groups. Analysis of mtDNA shows the Asian species form two distinct groups, one of langurs and the other of the "odd-nosed" species. The grey langurs are not closely related to either.