The Tarai gray langur (Semnopithecus hector), is a species of gray langur, and was formerly considered a subspecies of the Northern plains gray langur. The species is listed as Near Threatened, as there are probably not many more than 10,000 mature individuals, and it is experiencing a continuing decline. It is one of several Semnopithecus species named after characters from The Iliad, along with the Kashmir gray langur and Tufted gray langur.