In a rainforest teeming with snakes, spiders, and all manner of hidden beasts, a massive newly discovered insect is unlike anything Australian scientists have ever seen.
Researchers in Queensland’s Wet Tropics region have discovered a new species of stick insect named Acrophylla alta — and it may be the heaviest insect ever found in the country.
The newly classified species weighs in at 44 grams (roughly the weight of a golf ball) and stretches up to a staggering 15.75 inches in length.
Scientists have discovered a new stick insect species, Acrophylla alta, in a remote northeastern Australian rainforest, which may be the country’s heaviest, weighing about as much as a golf ball https://t.co/llOmzFVqD5 pic.twitter.com/IlOKPV9atG
— Reuters (@Reuters) July 31, 2025
“From what we know to date, this is Australia’s heaviest insect,” James Cook University researcher Professor Angus Emmott said in a media statement. He added that the insect’s unusually large size is likely an evolutionary adaptation to the cool, damp rainforest canopy it calls home.
“Their body mass likely helps them survive the colder conditions, and that’s why they’ve developed into this large insect over millions of years,” he explained.
So how do you find a monster insect that’s been hiding in plain sight? Social media, of course.
Emmott explained that the discovery began when his co-author, Ross Coupland, spotted a photo of an unusually large stick insect online.
“Ross immediately thought that it might be something new,” Emmott said. The duo then spent several nights searching the high-altitude forests between Millaa Millaa and Mount Hypipamee before finally spotting a massive female high up in the canopy so high they had to use a long stick just to get her down.
As is often the case in entomology, the secret was in the eggs.
“With stick insects, the eggs are very diagnostic,” said Emmott. “Every different species has slightly different eggs… different surfaces and different textures and pitting, and they can be different shapes.”
The team collected the eggs and confirmed the find: Acrophylla alta was indeed a brand-new species, now officially documented in the peer-reviewed journal Zootaxa. Two specimens have since been added to the Queensland Museum’s collection.
But the story isn’t over. Scientists still need to locate a male A. alta, which is proving elusive.
“You really need to find the male copulating with the female,” Emmott explained, noting that it’s the only way to confirm the pair as the same species. And given how different male and female stick insects can look, misidentification is a risk.
Queensland Museum’s entomology expert Dr. Nicole Gunter said the discovery shines a light on just how much is still unknown about Australia’s vast insect population.
“Australia is home to an immense amount of biodiversity that has yet to be classified and given a scientific name,” she told the Guardian, estimating that up to 70% of Australian insect species remain undescribed. And without a name, there’s no way to protect them.
“Recognizing this species as distinct is also important for its conservation,” Gunter noted. “We can’t conserve a species if we don’t know it exists or where it occurs.”
For now, Acrophylla alta remains an elusive giant in the treetops reminding us just how little we know about the world above our heads.