Chester Zoo welcomes 'ping pong ball-sized' twin monkeys

Eastern pygmy marmosets are one of the smallest species of monkey in the world

A pair of the world's smallest species of monkey, each "no bigger than a ping pong ball", have been born at Chester Zoo.

The tiny eastern pygmy marmoset twins each measured 2ins (5cm) in length and 0.3oz (10g) in weight at birth.

Primate keeper Holly Webb said despite their "almost unbelievable" size, the pair were "already very inquisitive".

The species, native to northern South America, is threatened by habitat loss in the wild.

Ms Webb said it was "wonderful to see new additions within the marmoset family and it's almost unbelievable just how small the babies are when they are first born".

"They are no bigger than a ping pong ball," she added.

Primate keeper Holly Webb said the pair were "already very inquisitive"

A spokesman said the pair are so small, it will be some time before keepers are able to determine their sex.

The zoo's deputy curator of mammals Dr Nick Davis said their size was no barrier to them being heard, as "despite their tiny stature, pygmy marmosets make a lot of loud noises".

The pair, which arrived in September but have only just made their public debut, will grow to about 8ins (20cm) in length and 4.5oz (130g) in weight in adulthood.