The bee was thought to be extinct until it was rediscovered in 1981 by United States entomologist Adam Messer, who found six nests on the island of Bacan and two other nearby islands.
The bees build communal nests on termite dwellings, researcher Adam Messer observed in the 1980s.
The world's largest bee, which had not been seen by scientists since 1981, has been rediscovered by a team of conservationists and worldwide researchers in a remote part of Indonesia. Scientists last saw the bee alive in 1981, but that changed recently thanks to a team of researchers in northern Indonesia.
"If you can get that much money for an insect, that encourages people to go and find them", expedition member Simon Robson, a biologist at the University of Sydney in Australia, told the New York Times.
Little is known about these elusive insects' habits.
The newly rediscovered Wallace's Giant Bee, also called "Raja ofu", or king of bees, has gained widespread media attention. "The female Wallace's giant bee that we found was very calm and unthreatening and showed no sign of aggression toward our team".
Scientists are already looking for Wallace's giant bee in other locations; conservationists are also pushing for legal protections for the insect.
"It was absolutely breathtaking to see this "flying bulldog" of an insect that we weren't sure existed anymore, to have real proof right there in front of us in the wild", said Clay Bolt, the photographer who captured the first image of the insect.
Together, the two hatched a plan to travel to Indonesia to find the bee.More news: The most logical landing spots for Antonio Brown
Despite its size, nearly nothing known was known about the female's secretive life cycle apart from that it lives largely alone and burrows in termite mounds, which it coats with waterproof resin.
After coming up empty handed for days, the team finally located a single female Megachile pluto hiding out in a termite nest. "I simply couldn't believe it: We had rediscovered Wallace's Giant Bee".
Wallace, who encountered thousands of rare and unique species during his expeditions, devoted only a single line of his journal to the bee.
While the bee has once-again been found, it's hard to say how long it will stay.
Wallace's Giant Bee is threatened by deforestation and habitat loss, according to the National Geographic.
As for the other discovered species, clips from the trip and rediscovery of the Wallace's giant bee are now being compiled and produced into a documentary film: "In Search of the Giant Bee".
Female specimens of the bee can reach a length of 3.8 centimetres and have a wingspan of more than six centimetres.