Newly Discovered Giant Stick Insect Species in Australia

Australian entomologists unveil a remarkable new species from the Stick Insect genus Acrofella, identified from two female specimens and their eggs.

Originally described in 1835, Acrofella is a genus of stick insects belonging to the tribe Phasmatini.

Species in this genus inhabit nearby regions including China, Australia, New Guinea, Tasmania, and Lord Howe Island.

The newly classified Acrofera species is found in the highlands of the Wettropic Bioregion in Queensland, Australia.

“Key locations include Lewis National Park, Evelyn Tableland (likely encompassing Maarlan National Park), Topaz, Upper Baron, Mount Hypamie, and Dumbra,” stated Professor Angus Emmott from James Cook University and his colleague Ross Coupland.

The new species, named Acrofera Alta, can reach lengths of up to 40 cm (16 inches) and weigh approximately 44 g.

Typically light brown in color, this species is exceptionally camouflaged despite its large size.

“Although there are long stick insects in this region, they tend to have relatively light bodies,” explained Professor Emmott.

“As far as we know, this is Australia’s heaviest insect.”

The eggs of Acrofera Alta were also crucial in distinguishing it as a new species.

“Every stick insect species has distinct egg characteristics,” noted Professor Emmott.

“Their surfaces, textures, and corrosion patterns vary. Shapes can differ as well.”

“Even the caps of the eggs are uniquely identifiable.”

Researchers speculate that Acrofera Alta may not have been discovered earlier due to the inaccessibility of its habitat.

“Their environment could explain their large body size,” Professor Emmott added.

“It is a cool, damp habitat.”

“Larger body weight might enable them to endure colder temperatures, which could have led to their evolutionary characteristics over millions of years.”

The identification of such a large new insect species highlights the critical need to conserve remaining biologically diverse habitats and ecosystems, with potential undiscovered species like stick insects awaiting description.

The discovery of Acrofera Alta has been documented in a study published in the journal Zootaxa.

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Ross M. Coupland and Angus J. Emmott. 2025. New giant species of Acrofella Gray, 1835 (Fasmida: Fasmida), from the highlands of Wettropic, Queensland, Australia. Zootaxa 5647(4): 371-383; doi: 10.11646/zootaxa.5647.4.4