The Admiral's Insect

Kelly’s Field Notes

Common Name: Stick insect, Phasmid, stickbug, walking stick, Tree Lobster, Lord Howe Island Stick Insect

Order: Phasmatodea

Family: Phasmatidae

Genus: Dryococelus

Species: australis

Note: “Phasmids” as a common name sometimes refers to members of the order of Phasmatodea in addition to those of the family Phasmatidae. There are many overlaps in life histories within this order.

General Phasmid Description:

Phasmids are found on every continent save Antarctica. They have an incomplete metamorphosis (egg, nymph, adult). They are part of the same super order (Polyneoptera) as roaches, mantids, grasshoppers, and crickets. Their forewings are leathery (like roaches) and the adult males of some species can take short flights. The Australian stick insect (Extatosoma tiaratum) are decent flyers, for example. Adult females have either no wings or nonfunctioning wings. Nymphs can actually glide despite not having wings (Zeng et al, 2020). Phasmids are highly sexually dimorphic, with females generally being much larger than males (likely to carry eggs).

Phasmids are masters of disguise! Many phasmids sway back and forth to mimic branches moving in a breeze. Some can even change colors over molts to match their surroundings.

Some can be huge! The longest insect in the world is Phryganistria chinensis, a stick insect that is 62.4 cm (24.6 in) in length, including its legs, 37.1 cm (14.6 in) of only body (Baggley, 2016). This species is fairly newly discovered, as of 2016.

Phasmatodeans come by many common names depending on their shape: stick insects, stick bugs, walkingsticks, ghost insects, leaf insects, leaf bugs, walking leaves. The phasmatodeans in family Phylliidae resemble leaves in shape and color (Bank et al, 2021). Their camouflage is so convincing some have fake decay spots, leaf veins, and textured edges. Maybe we’ll do an episode about them in the future.

Phasmatodeans are a very old group! We have a trace fossil of a relative of modern phasmatodeans, Phasmichnus radagasti, dating back to the Permian Period (~250-300 million years ago) (Logghe et al, 2021). Trace fossils are imprints, not body fossils, and cannot be precisely placed within a phylogenetic tree (evolutionary relationship of organisms visualized as a branching tree). We do have full body fossils of the leaf insect Eophyllium messelensis, which is ~47 mya during the Paleogene Period (Wedmann et al., 2007). This fossil is our oldest example of a leaf insect.

Tree Lobster Description: 

Juvenile LHI stick insects are diurnal active during the day) while adults are nocturnal (active at night). Due to this behavioral difference, juveniles are green to blend in with leaves while adults are dark brown in color to blend in with the shadows of the night (Cleave, 2017). Adults can reach 20 cm (7.87 in) in length and weigh 25 g (0.88 oz). Males are about 25% smaller than females (Lord Howe Museum, 2025). 

General Phasmid Life Cycle:

Some species of phasmids engage in myrmecochory. Phasmid eggs are coated in an edible structure that ants love. The ants take the eggs back to their nest, eat the coating, and allow the phasmid egg to hatch unharmed. This is also a strategy some plants use for seed dispersal (Michaelson, 2024).

Tree Lobster Life Cycle: 

Lord Howe Island stick insects insert their eggs into the soil or leaf litter. They are brown and about 3-4 mm in length. Females can produce up to 300 eggs in their lifetime (San Diego Zoo Wildlife Alliance, 2025). The eggs have a very long incubation period of 6-9 months (Cleave, 2017). The eggs are drought-resistant. Nymphs are about 10 mm (0.4 in) long upon hatching. They feed primarily on tea tree leaves (Melaleuca howeana) (Priddel et al., 2004). Nymphs take several months to reach adulthood. Their full lifespan is between 12 and 18 months (San Diego Zoo Wildlife Alliance, 2025). 

LHI stick insects, like other stick insect species, can reproduce via parthenogenesis (females lay unfertilized eggs which hatch into clones of the mother) (Stuart et al., 2024).

Males grip females’ legs to maintain pair bonding and to guard her against other rival males (like hand holding!).

Super Powers:

• Climbing - these insects are excellent climbers with sticky toes

• Camouflage - LHI stick insects have excellent camouflage that changes when they go from active in the day juveniles to nightlife adults.

• Thanatosis - Many species of stick insect, including the tree lobsters,  play dead when threatened! Much like opossums or hog nosed snakes. 

• Parthenogenesis - stick insects can reproduce without males! Females lay unfertilized eggs that produce clones of the mother.

• Flight - some male phasmids can fly!

• Gliding - nymphs, though wingless, can glide.

• Autotomy - phasmids can drop legs when threatened, then regenerate them on their subsequent molts

• Chemical Spray - some species of Phasmatodea, such as Asceles glaber, can spray a noxious chemical at predators. It can cause temporary blindness in vertebrates.

Lord Howe Island Insects and Humans:

LHI stick insects were thought to be extinct on Lord Howe Island after black rats (Rattus rattus) were introduced in 1918 from the Scottish supply ship SS Makambo (Travers, 2025). They were also commonly used as bait for fishing. They were presumed extinct by 1920. In the decades after the SS Makambo ran aground, five species of birds and 13 species of invertebrates went extinct (Lord Howe Island Museum, 2025).

A new population was discovered in 2001 on Ball’s Pyramid, a volcanic outcrop 23 km off the coast of Lord Howe Island. A tiny population of between 24 and 40 individuals were found on a single tea tree bush (Crew, 2014). There are 20-30 individuals currently left in that originally found population (Zoos Victoria, 2025). Previously, in 1964 and subsequent years, dead LHI stick insects were found by climbers but no living examples (Krulwich, 2012).

The Melbourne Zoo has a breeding population of LHI stick insects which started in 2003. In 2008, Zoo-born LHI stick insects were introduced to Lord Howe Island. There is now a greater captive breeding program supported by the Lord Howe Island Board, with the Melbourne Museum (AUS), Bristol Zoo (UK), and San Diego Zoo (US). Since the program began, Melbourne Zoo has hatched more than 14,000 nymphs (Cleave, 2017).

Journal Articles About the Return and Captive Breeding:

Priddel, David, et al. "Rediscovery of the ‘extinct’Lord Howe Island stick-insect (Dryococelus australis (Montrouzier))(Phasmatodea) and recommendations for its conservation." Biodiversity & Conservation 12.7 (2003): 1391-1403.

Honan, Patrick. "The Lord Howe Island stick insect: an example of the benefits of captive management." Victorian Naturalist, The 124.4 (2007): 258-261.

Honan, Patrick. "Notes on the biology, captive management and conservation status of the Lord Howe Island Stick Insect (Dryococelus australis)(Phasmatodea)." Insect conservation and islands. Dordrecht: Springer Netherlands, 2008. 205-219.

Other Animals We Thought Were Extinct But Later Re-Discovered (Strauss, 2022; Williams, 2025):

• Coelacanth (Order Coelacanthiformes) - thought extinct for millions of years, rediscovered in 1938)

• Victorian grassland earless dragon (Tympanocryptis pinguicolla) - thought extinct in 1969, rediscovered in 2023

• Cuban solenodon (Atopogale cubana) - declared extinct in 1970, rediscovered in 1974

• Wallace's giant bee (Megachile pluto) - thought extinct in the 1960’s, rediscovered in 2019

• Attenborough's long-beaked echidna (Zaglossus attenboroughi) - thought extinct in 1961, rediscovered in 2023

• Chacoan peccary (Catagonus wagneri) - only seen in fossils, first live specimen seen in 1971 (locals probably knew these guys were around but scientists did not)

• New Guinea big-eared bat (Pharotis imogene) - thought extinct around 1914, rediscovered in 2012

• Terror Skink (Phoboscincus bocourti) - thought extinct in 1876, rediscovered in 2000

• Antioquia brushfinch (Atlapetes blancae) - thought extinct in the 1960’s, rediscovered in 2018

• Majorcan Midwife Toad (Baleaphryne muletensis) - found only as fossils, rediscovered in 1977

• Laotian rock rat (Laonastes aenigmamus) - thought extinct over 10 mya, rediscovered in 2005

• Mountain pygmy possum (Burramys parvus) - found only as fossils, rediscovered in 1966

References:

Baggley, Kate. “World’s Longest Insect Is Two Feet Long.” Popular Science, May 2016, www.popsci.com/introducing-worlds-longest-insect/. Accessed 3 Jan. 2026.

‌Bank, Sarah, et al. "A tree of leaves: Phylogeny and historical biogeography of the leaf insects (Phasmatodea: Phylliidae)." Communications Biology 4.1 (2021): 932.

Cleave, Rohan. “VIP: Very Important Phasmid.” Australian Museum, 6 May 2017, australian.museum/blog/museullaneous/vip-very-important-phasmid/.

Krulwich, Rovert. “Six-Legged Giant Finds Secret Hideaway, Hides for 80 Years.” Krulwich Wonders: Robert Krulwich on Science, NPR WNYC, 29 Feb. 2012, www.npr.org/sections/krulwich/2012/02/24/147367644/six-legged-giant-finds-secret-hideaway-hides-for-80-years.

Logghe, Antoine, et al. "A twig-like insect stuck in the Permian mud indicates early origin of an ecological strategy in Hexapoda evolution." Scientific reports 11.1 (2021): 20774.

‌“Lord Howe Island Has Lost Nine Land-Birds.” Lord Howe Island Museum, 2025, lhimuseum.com/learn/extinct-birds/.

‌“Lord Howe Island Stick Insect.” San Diego Zoo Wildlife Alliance, 2025, animals.sandiegozoo.org/animals/lord-howe-island-stick-insect.

Michaelson, Julie. “Myrmecochory: How Ants Shape Plant Communities.” Xerces Society, 11 June 2024, xerces.org/blog/myrmecochory-how-ants-shape-plant-communities. Accessed 3 Jan. 2026.

Priddel, David, et al. "Rediscovery of the ‘extinct’Lord Howe Island stick-insect (Dryococelus australis (Montrouzier))(Phasmatodea) and recommendations for its conservation." Biodiversity & Conservation 12.7 (2003): 1391-1403.

“Lord Howe Island Stick Insect.” Zoos Victoria, 2025, www.zoo.org.au/fighting-extinction/local-threatened-species/lord-howe-island-stick-insect/.

Strauss, Bob. 11 Living Species That Were Once Thought to Be Extinct. Treehugger, 25 July 2022, www.treehugger.com/living-species-once-thought-extinct-4117748.

Stuart, Oliver P., et al. "Pedigree reconstruction in a species with a mixed reproductive mode." Genetic and phenotypic evolution of the Lord Howe Island stick insect, Dryococelus australis (Montrouzier, 1855), in captivity (2023): 103.

Travers, Scott. “Driven to “Extinction” by a Shipwreck, a 2001 Discovery Brought the “World’s Rarest Insect” back to Life.” Forbes, 08 Jan. 2025, www.forbes.com/sites/scotttravers/2025/01/06/driven-to-extinction-by-a-shipwreck-a-2001-discovery-brought-the-worlds-rarest-insect-back-to-life/.

Wedmann, Sonja, Sven Bradler, and Jes Rust. "The first fossil leaf insect: 47 million years of specialized cryptic morphology and behavior." Proceedings of the National Academy of Sciences 104.2 (2007): 565-569.

Williams, Leoma. “Back from the Dead: Meet 10 Animals Once Presumed Extinct.” Discover Wildlife, BBC Wildlife Magazine, 3 Feb. 2025, www.discoverwildlife.com/animal-facts/animals-once-presumed-extinct.

Zeng, Yu, et al. "Canopy parkour: movement ecology of post-hatch dispersal in a gliding nymphal stick insect, Extatosoma tiaratum." Journal of Experimental Biology 223.19 (2020): jeb226266.