This beauty is Nepenthes bicalcarata (Caryophyllales - Nepenthaceae), a large and impressive pitcher plant famous for the two menacing fang-like spines projecting downward from its lid, which distinguish it from any other Nepenthes species. The pitcher color of this species is typically yellowish green or orange, and occasionally red.
As you know, all Nepenthes species are carnivorous, and are equipped with large, modified, pitcher-shaped leaves with which to trap and digest small organisms. But, the Fanged Pitcher Plant has also developed a mutualistic relationship with the ant Camponotus schmitzi, which nests in the hollow tendrils of the plant, and is able to run up and down the walls of the pitchers without falling in, enabling it to hunt in the pitcher fluid. In an unusual twist, these ants help the Fanged Pitcher Plant not by feeding it, but by removing some of its larger prey. When pitcher plants catch large insects or other large prey, the animal can begin to decay before being digested, and this putrefaction can spread to the pitcher and shorten its lifespan. The ants specifically haul out these larger items from the pitcher, breaking them into smaller pieces to feed upon, and thereby also benefit from this strange relationship.
Nepenthes bicalcarata is found only on the island of Borneo, in Brunei Darussalam, Kalimantan (Indonesia), and Sabah and Sarawak (Malaysia). Currently, this species is regarded as Vulnerable on the IUCN Red List.