A long-lost giant bee, which had not been seen since 1981, has been rediscovered by scientists in an Indonesian rainforest.

Mechachile Pluto, also known as Wallace’s giant bee, is four times the size of a honeybee and the largest in the world, with its females growing a wingspan of more than 6cm and huge, well-developed jaws.

A team of US and Australian conservationists and scientists who found the bee in January in the North Moluccas islands in northeast Indonesia described the moment as the “holy grail” of species discoveries.

The single female bee was found living in a termites’ nest in a tree, more than two metres off the ground. The team said it had scoured and observed similar brown soil termite mounds, where the bee is known to burrow, for five days before having any success.

Simon Robson, an Australian biologist who joined the expedition, funded by the Global Wildlife Conservation group, told National Geographic magazine that they were discouraged and about to call it a day when they searched one last mound which had a tiny hole in it.