 Though scientists have known of its existence since the early 19th century, it was positively identified as being a distinct species in its own right in 2006, having long been believed to be a subspecies of the mainland clouded leopard ("Neofelis nebulosa").WWF quoted Dr. Stephen O'Brien of the U.S. National Cancer Institute as saying, "Genetic research results clearly indicate that the clouded leopard of Borneo should be considered a separate species".Some journalists have pointed out, though, that this taxon is previously known as a subspecies, and claim that the WWF announcement of a new species was more designed to draw attention to its endangered status.