Have You Seen This Scorpion Tailed Spider?

We found this spider on a jarrah tree in the Stinton Cascade Reserve in Karragullen two years ago and have not seen one since. Some desktop research revealed that it belongs to the genus Arachnura of the family Araneidae. They are common in the eastern states but to our knowledge there have been no described species from WA. It is quite possible that this is a new species; the colouration of this spider is quite different from those in the east which are most commonly a golden brown or fawn colour.

This genus is distributed throughout South East Asia from Japan to India and Australasia, and there is also a species from Africa and Madagascar. Spiders of this genus typically build an orb web 1 to 2 metres from the ground close to foliage. The web is inclined and has a V-shaped section missing at the top from which the female hangs a series of yellowish woolly egg sacs, which are sometimes camouflaged with debris, in late summer and autumn.

They are often found in large numbers near water. Only the females have the distinctive scorpion like tail, which they curl up in much the same fashion as a scorpion when disturbed. The tail is completely harmless though and is thought to have evolved to resemble a twig as camouflage, or as a kind of mimicry of the more dangerous scorpion.

The colour of this spider would indicate the latter because, in nature, a combination of red (or orange), yellow and black commonly indicate that an animal is in some way dangerous and should be left alone. Other, harmless animals may adopt these colours and mimic a dangerous counterpart to avoid predation. Given that other spiders of this genus are not dangerous, it is unlikely that this one is either and is therefore probably a mimic.

We would like to know more about this ‘as yet unknown' local species so if you do see it, please get in touch with us by emailing This email address is being protected from spambots. You need JavaScript enabled to view it. and let us know where you saw it.