Simply Horrible: A Female Giant Insect Was Discovered Using a Photo on Social Media

A huge stick insect found in highland tree scrub in Australia. At 40cm long, Acrophylla alta weighs slightly less than a golf ball and is possibly the heaviest insect in Australia.

The new species, growing to 40cm in length and named Acrophylla alta, was discovered at high altitudes in the Atherton Tablelands of northern Queensland, and scientists believe this habitat may be one of the reasons for its large size, The Guardian reports.

A peer-reviewed study documenting the discovery, published in the journal Zootaxa, notes that the stick insect was likely heavier than the giant burrowing cockroach, which is endemic to Queensland and is currently the heaviest insect in Australia.

Professor Angus Emmott, a researcher at James Cook University, said the discovery was helped by a post on social media.

Emmott said his co-author Ross Copeland was sent a photo of the stick insect and he "immediately thought this might be something new."

After a long night of searching, Emmott and Copeland found a large female between Millaa Millaa and Mount Gipipami. The insect was so high up that they had to use a long pole to pull it down, The Guardian reports.

As soon as Copeland saw the female up close, he was sure it was a new species of stick insect. The pair took her back to Emmott's house in Atherton Tablelands for further study.

They kept the female in a cage, fed her, and then collected her eggs. “Stick insect eggs are very important for diagnosis, and so each species has slightly different eggs,” Emmott explains.

Angus Emmott said he believed the species had not been discovered before because its habitat was too inaccessible.

"It lives high in the tree canopy, so unless it's dropped on you by a cyclone or a bird, very few people will see it," Emmott said in a statement.

But habitat may also explain why stick insects are larger, he said, noting that body mass may help them survive in cold conditions in the "cool, wet environments where they live."

The next step to learning more about this species is to find a male, which turns out to be no easy task, and not just because they are stick-thin.

Male stick insects are generally much smaller and visually distinct from females, so much so that in other cases pairs have been described not only as different species, but also from different genera.

"You really need to see a male copulating with a female," Emmott said. "Then you know what it is, and by collecting the eggs you can really see that it's the same thing."

Queensland Museum entomology expert Nicole Gunter said the discovery filled a gap in knowledge about Australia's biodiversity.

She said it also highlighted the amount of biodiversity we still have to learn about some of Australia's largest insect species. "Australia is home to a huge amount of biodiversity that has yet to be classified and given a scientific name."

She estimates that up to 70% of Australian insect species are currently undescribed.

"Recognising this species as distinct is also important for its conservation. We cannot conserve a species if we do not know whether it exists or where it occurs."

She said the stick insect species had so far only been recorded in a small number of woodland sites in the Wet Tropics of Queensland.

Future research could help improve scientific understanding of the insect's distribution and any potential threats the species faces.