Australian researchers have identified two new large stick insect species in far north Queensland, according to a study published in Austral Entomology, illustrating how little is still understood about insect diversity. Led by Dr Braxton Jones of the University of Sydney, a team of scientists combined DNA analysis, museum collections, citizen science records, and field surveys to revise the taxonomy of native phasmids. The findings reveal that what scientists previously categorized as two distinct species are actually five separate species inhabiting ranges stretching from northern New South Wales into tropical north Queensland.
Hiding in Plain Sight: The Discovery of Anchiale robusta
One of the newly described species, named Anchiale robusta, was long popular among insect enthusiasts and scientists alike, but had been misidentified for decades due to a case of mistaken identity, according to Jones. Field researchers noticed that groups of individuals looked morphologically distinct and lived in different habitats, prompting a closer investigation. Female Anchiale robusta grow to a body length of 12 to 16 centimeters, while males reach 9 to 10 centimeters. Jones noted that while most specimens feature black wings, some individuals display a hint of purple on the underside of their hindwings. Males are consistently smaller than females, a size disparity that allows lighter males to fly while heavy, egg-laden females remain flightless.
The Mabi Rainforest Specialist: Anchiale mabiensis
The research team also formally described Anchiale mabiensis, a species restricted to the critically endangered Mabi rainforest on Queensland’s Atherton Tablelands. Females of this species measure roughly 11 to 12 centimeters in length. According to Jones, the eggs of Anchiale mabiensis feature an unusual structural “lid” that detaches when the young insects hatch. Because these insects occupy smaller habitat ranges than previously understood, the discovery carries critical conservation implications for managing fragmented tropical ecosystems.
Did you know? Animals of the Anchiale genus rank among the most documented stick insects on citizen science platforms because populations can hatch in large proportions, yet major taxonomic gaps remain, according to Jones.
Comparing Australia’s Heavyweights: Acrophylla alta vs. Anchiale
The discovery arrives alongside other recent findings in the same region. Last year, scientists on the Atherton Tablelands described Acrophyla alta, a 40-centimeter-long stick insect weighing 44 grams (1.55 oz)—roughly the same as a golf ball. According to Angus Emmott of James Cook University, who helped identify the species, Acrophyla alta is believed to be Australia’s heaviest insect. Emmott explained that the creature’s immense body mass is likely an evolutionary response to its cool, wet, high-altitude canopy habitat, helping the insect survive colder conditions over millions of years. While Acrophyla alta is believed to be the heaviest, Australia’s longest stick insect is found in northeastern Queensland, where females can exceed half a meter in length.
Frequently Asked Questions
Where were the new stick insect species discovered?
Both new species were found in far north Queensland, with Anchiale mabiensis specifically localized to the Mabi rainforest on the Atherton Tablelands, according to the published research.
How big do the newly identified species grow?
Female Anchiale robusta reach lengths of 12 to 16 centimeters, and males grow to 9 to 10 centimeters. Females of Anchiale mabiensis measure approximately 11 to 12 centimeters long.
What makes Australia’s Acrophylla alta unique?
Discovered in high-altitude rainforest canopies, Acrophyla alta grows up to 40 centimeters long and weighs 44 grams, making it believed to be the heaviest insect in Australia.
Explore More: Dive deeper into Australia’s unique biodiversity by checking out our latest coverage on tropical rainforest conservation and native wildlife discoveries. Share your thoughts on these findings in the comments below.