After eluding researchers for nearly four decades, the world's largest bee has been discovered alive and well on a densely forested Indonesian island.

“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,” Clay Bolt, a natural history photographer specializing in bees, said in a statement. “To actually see how beautiful and big the species is in life, to hear the sound of its giant wings thrumming as it flew past my head, was just incredible."

First discovered by Alfred Russel Wallace in 1859, Megachile pluto, also known as "Wallace's giant bee," has a body measuring roughly 1.5 inches long and a wingspan of nearly 2.5 inches. It also features a set of imposing pinchers, which it uses to gather resin and wood for its nest. The species is so incredibly rare and elusive, that it wasn't seen again until 1981 when American biologist Adam Messer discovered the nests of six solitary giants.

“Messer’s rediscovery gave us some insight, but we still know next to nothing about this extraordinary insect,” said trip member and bee expert Eli Wyman, an entomologist at Princeton University.

A hard bee to find

Wallace's Giant Bee, the world's largest species of bee, being photographed outside its nest somewhere in the Indonesian islands of North Moluccas. Wallace's giant bee, the world's largest species of bee, being photographed outside its nest somewhere in the Indonesian islands of North Moluccas. (Photo: © Simon Robson)

In the quest to find a bee that many feared had gone extinct, Bolt and his team traveled to the Indonesian islands known as the North Moluccas in January 2019. Both the location and timing matched the earlier discoveries made by both Wallace and Messer. They also knew that the giant bees had a preference for using arboreal termite mounds for their nests. For four days, the team and local village guides climbed ladders and started at termite mounds for 20 minutes at a time for signs of the bee. On the fifth day, with all members of the team suffering from various illnesses, they decided to check out one more mound about eight feet off the ground.

"Eli climbed up and immediately felt for certain that it was a bee nest," Bolt wrote in an account of the discovery. "The structure was just too perfect and similar to what we expected to find. I climbed up next and my headlamp glinted on the most remarkable thing I’d ever laid my eyes on. I simply couldn’t believe it: We had rediscovered Wallace’s Giant Bee."

After capturing the female specimen, the team took photos and video (shown below), and then carefully returned the bee to her nest. "We were elated," added Bolt.

The sting of regret

As you might expect, the world's largest bee also comes with a giant stinger. Surprisingly, however, the one thing the researchers lamented was the fact that they did not have the opportunity to feel its punch.

“We were very keen to be stung by the bee,” professor and team member Simon Robson told the Sydney Morning Herald. "People who work on bees get very excited about the pain levels of various bees, whether it's indifferent or like being shot by a bullet. But because we only found one, we did not want to harass it too much."

Now that the bee's rediscovery has been made public, the team is working with Indonesian researchers and conservation groups to help protect the critical habitat necessary for its survival. According to Global Wildlife Conservation — which earlier named the bee to its top 25 most wanted species in its Search for Lost Species program — forest destruction for agriculture is a growing issue for the Indonesian archipelago.

“I hope this rediscovery will spark future research that will give us a deeper understanding of the life history of this very unique bee and inform any future efforts to protect it from extinction," added Wyman.

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.

Scientists rediscover the world's largest bee
Dubbed the 'flying bulldog,' this extremely rare bee has been lost to science since 1981.