Hatinh langur
Trachypithecus hatinhensis
The Hatinh langur is a highly threatened Old World monkey found in limestone forests in Vietnam, primarily in the Quảng Bình Province. They are a primarily black, arboreal, and diurnal monkey. They occupy dense forests which contribute to their decline as a result of habitat fragmentation. They're also subject to hunting from humans which further contributes to their endangered status.