Dendrocnide moroides

Dendrocnide moroides
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Rosales
Family:	Urticaceae
Genus:	Dendrocnide
Species:	D. moroides
Binomial name
Dendrocnide moroides (Wedd.) Chew

Dendrocnide moroides, also known as the stinging bush, gympie stinger, mulberry-leaved stinger, gimpi gimpi, gympie,^[1] stinger or moonlighter, is a large shrub native to rainforest areas in north half of eastern Australia, the Moluccas and Indonesia.^{[ 1][ 1][ 1]} It is best known for stinging hairs which cover the whole plant and deliver a potent neurotoxin when touched. It is the most virulent of the Australian species of stinging trees.^{[ 1][ 1]}

D. moroides usually grows as a single-stemmed plant reaching 1–3 metres in height. It has large, heart-shaped leaves about 12–22 cm long and 11–18 cm wide, with finely toothed margins.

Ecology

The species is unique in the Dendrocnide genus in having bisexual inflorescences in which the few male flowers are surrounded by female flowers.^{[ 1]} The flowers are small, and once pollinated, the stalk swells to form the fruit. Fruits are juicy and mulberry-like and are bright pink to purple. Each fruit contains a single seed which is on the outside of the fruit.^{[ 1]}

The species is an early coloniser in rainforest gaps; seeds germinate in full sunlight after soil disturbance. Although relatively common in Queensland, the species is uncommon in its southern-most range, and is listed as an endangered species in New South Wales.^{[ 1][ 1]}

The giant stinging tree and the shining-leaved stinging tree are other large trees in the nettle family occurring in Australia.

Toxicity

Contact with the leaves or twigs causes the hollow, silica-tipped hairs to penetrate the skin. The sting causes an extremely painful stinging sensation which can last for days or even months, and the injured area becomes covered with small, red spots joining together to form a red, swollen mass. The sting is known to be potent enough to kill humans, and it can also kill dogs and horses.^{[ 1]} However, the sting does not stop several small marsupial species, including the red-legged pademelon, insects and birds from eating the leaves.^{[ 1]} 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.^{[ 1]}

Treatment

The recommended treatment for skin exposure to the hairs is by pulling them out with a wax hair removal strip.^{[ 1][ 1]}

Cases

A research scientist named Marina Hurley spent three years studying the stinging trees in Atherton Tableland (Queensland), wearing protective clothing. Her initial symptoms that lasted for hours involved sneezing fits, watering eyes and a runny nose, but the allergy became more severe with repeated exposure; in one incident she had to be hospitalized. Her extreme itching and urticaria requiring steroid treatment.^{[ 1]}

References

Further reading

• Stewart, Amy (2009). Wicked Plants: The Weed that Killed Lincoln's Mother and Other Botanical Atrocities. Etchings by Briony Morrow-Cribbs. Illustrations by Jonathon Rosen. Algonquin Books of Chapel Hill. ISBN 978-1-56512-683-1. 

Wikimedia Commons has media related to Dendrocnide moroides.

External links

• Dendrocnide at Department of Biology, Davidson College