The 'Dendrocnide moroides', commonly known in Australia as the Gympie-Gympie, Gympie stinger, stinging bush (or tree), mulberry-leaved stinger, or simply stinger, is a plant in the nettle family 'Urticaceae' found in rainforest areas of Malesia and Australia. It has large, heart-shaped, simple leaves about 12–22 cm (5–9 in) long and 11–18 cm (4–7 in) wide with toothed margins, a pointed tip, and a cordate to the obtuse base shape.

The nettle family is full of stinging plants, but none is quite as aggressive as the Gympie Gympie. One of six such trees native to Australia and also found in Indonesia and in Malesia, the Gympie Gympie is one of the most dangerous plants in the world. Their leaves trigger an intense allergic reaction in its victims, sometimes even causing anaphylactic shock. The wound can cause excruciating, debilitating pain for months. Many people have reported flare-ups of the pain for many years afterward, and there are several accounts of horses, mad with pain, jumping off cliffs to their deaths after being stung.

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