Giant Thorny Walking Stick

ORDER: Phasmida

FAMILY: Bacillidae

GENUS: Heteropteryx

SPECIES: dilatata

Female grows to 15 cm (6 inches) in body length and is heavily built. (From above she is seen as a stretched pointy oval leaf.) She has a long ovipositor, medium long antennae and legs, and a thorny head and body. Female is green and has rudimentary bright pink wings. Male is smaller than the female, growing to 12 cm and is more slender and stick-like. He is brown, has long striped antennae, thorny head and legs, and functional plum-colored wings.

Western Malaysia. Forests and shrubs.

Herbivorous. Leaves from large-leafed trees. Will eat mainly blackberry leaves here, but can also eat rose, oak and English ivy leaves.

Nocturnal. Reproduction is bisexual. 100 to 150 brown eggs are deposited in the ground and incubation takes 11 months. Nymphs take 11 months and 6-7 molts to become adults. An adult female lives for as much as a year, a male about 8 months.

Like many insects, stick insects can regenerate lost appendages over the course of several molts. These insects remain motionless during the daytime, usually hanging inverted between leaves in a tree. The brown nymphs hang from the branches with the abdomen sticking out like a little crumpled leaf; if disturbed they will drop to the ground like a dead leaf.

There are around 3000 known species of stick and leaf insects, most of which come from the tropics. The longest insect in the world is a walking stick that is over a foot long. Though most stick insects rely on passive camouflage in order to avoid predators, some of the larger species such as this one have large spines on their hind legs which can serve in self defense as well as in competition between males. This phasmid is also known as the Malayan Stick Insect.

The Giant Thorny Walking Sticks can be found in the Bug House in the Wayne and Gladys Valley Children's Zoo.

Not endangered, except for loss of habitat. This animal has not yet been evaluated by the IUCN.


  1. Internet: "The Stick Insects"at; "Heteropteryx dilatata" at
  2. Schlager, Neil, Ed. Grizmek
  3. Wootton, Anthony. Insects of the World. 1984. Facts on File, Inc.,New York.
  4. Fink, Adam. Keeper, Oakland Zoo.