Dendrocnide moroides, also known as the stinging brush, mulberry-leaved stinger, gympie gympie, gympie, gympie stinger,stinger, the suicide plant, or moonlighter, is common to rainforest areas in the north east of Australia.It is best known for stinging hairs that cover the whole plant and deliver a potent neurotoxin when touched. It is the most toxic of the Australian species of stinging trees.The fruit is edible if the stinging hairs that cover it are removed.
Contact with the leaves or twigs causes the hollow, silica-tipped hairs to penetrate the skin. The hairs cause an extremely painful stinging sensation that can last anywhere from days to years, and the injured area becomes covered with small, red spots joining together to form a red, swollen welt. The sting is famously agonizing. Ernie Rider, who was slapped in the face and torso with the foliage in 1963, said:
For two or three days the pain was almost unbearable; I couldn’t work or sleep, then it was pretty bad pain for another fortnight or so. The stinging persisted for two years and recurred every time I had a cold shower. ... There's nothing to rival it; it's ten times worse than anything else.
However, the sting does not stop several small marsupial species, including the red-legged pademelon, insects and birds from eating the leaves.
Moroidin, a bicyclic octapeptide containing an unusual C-N linkage between tryptophan and histidine, was first isolated from the leaves and stalks of Dendrocnide moroides, and subsequently shown to be the principal compound responsible for the long duration of the stings.
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