Native stick insect identified

Ellen McKechnie, of Andersons Bay, asked:

I found this wee beastie in my garden on a buxus bush. What is it?

Jennifer Jandt, a zoologist at the University of Otago, responded:

You have found the ‘‘prickly stick insect’’ (Acanthoxyla

prasina). The prickly stick insect is native to New Zealand, and found throughout the North and South islands (though it is observed less often than other stick insects).

One of the reasons this insect is so difficult to find is because of its camouflage — not only does it look like a stick, but this species looks like a thorny stick. Most predators don’t want to eat thorny sticks.

Most prickly stick insects (and most stick insects, for that matter) that you find are females. Males have never been found in New Zealand, and to date, only one male has been discovered in England, where the species was accidentally introduced.

Stick insects can reproduce parthenogenetically — that means that they do not need to mate in order to lay viable eggs. Because of this, a lack of males in the population is expected.

Stick insects tend to eat leaves from a wide variety of plants, though rarely are they considered a pest species, nor do they cause much damage. They’re generally quite harmless.

If you’re interested in learning more about the prickly stick insect, I recommend checking out the article written in

Wikipedia under Acanthoxyla prasina.

There are some excellent images of the prickly stick insect posted on iNaturalist.nz (you can also check out the range of places where people have located them). It would be great if you could add your observation to the 107 observations posted on the database at iNaturalist.nz under acanthoxylaprasina.

You can find more information on other species of Acanthoxyla stick insects found in New Zealand from landcareresearch.co.nz under acanthoxyla.

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