The Latin word auratus in its scientific name means "golden" and refers to a less common color variant.

[5] The nominate subspecies Trachypithecus auratus auratus has a rare morph that does not lose its juvenile coloration when it matures, instead, the coloration darkens slightly, with yellow tinges on its sides, limbs, and around its ears, and a black tinge on its back.

[3] The East Javan langur inhabits the interior and peripheral areas of rainforests.

As with other colobines, it has evolved a specialised stomach to digest plant material more efficiently.

The brighter coloring of juveniles may alert females to their presence and ensure that they will always be noticed and protected.