Taronga Zoo is celebrating the birth of a bright orange Francois’ Langur, one of the world’s rarest monkeys.

The male infant, who keepers have named ‘Nangua’ after the Mandarin word for pumpkin, was discovered cradled in mother Meili’s arms on 7 November.

Also known as Francois’ leaf monkeys, Langurs are born with bright orange hair while their parents are black in colour. It is thought this colour distinction makes it easier for adults to identify and look after infants.

Senior Primate Keeper, Jane Marshall said Nangua was already receiving lots of attention from his mother and the harem group’s other females, Noel and Elke.

“Meili has shown her calmness and experience since the birth, cradling and protecting the baby, but also allowing Noel and Elke to get close to him,” said Jane.

Francois’ Langurs practice allomothering or ‘auntying’, in which other females participate in raising the baby. Infants can often be seen being passed around as each of the Langurs take turns caring for their newest addition.

“Noel has taken on the role of allomother, carrying the baby about 50 percent of the time. This gives mum a break to eat and rest, but as soon as the baby whimpers she races straight back over to him,” said Jane.

The infant is the second for Meili at Taronga, following the birth of a male named Tam Dao in 2011, and the first for father Bobo. Taronga’s dominant male arrived in Sydney from Beijing Zoo in 2010, as part of the international breeding program for his endangered species.

“Bobo is a little bit overwhelmed, but he’s doing really well. He’s protective of Meili and he’ll even let the baby climb onto him. I saw the baby climb up over his head the other day and he wasn’t worried at all,” said Jane.

Nangua has begun to explore his exhibit on Taronga’s Rainforest Trail to the delight of keen-eyed visitors.

“He’s still quite wobbly on his legs, but his head control is very strong and he’s gripping and climbing well. The adults are starting to let him climb off them briefly, which shows they’re happy with his progress,” said Jane.

Once widespread in China and Vietnam, Francois’ Langurs have become one of the world’s rarest monkeys due to habitat loss and poaching for traditional medicines. Taronga is the only zoo in Australia to care for these primates, but is working with other zoos globally to help ensure a future for the species.