Arachnura Higginsi

Arachnura Higginsi: Scorpion tailed spider.
Fucking cool. This is one of those species that you've never heard of, and when you see it, it blows your mind. The tail is prehensile!

It's actually quite common on the east coast of Australia - this one's in my garden, and there are 3-4 smaller ones around. This is the female, about 20mm long including the tail (they get up to about 30mm). The male is about 2mm long, brown, and with no tail. The female rests upside-down in the web, with the tail pointing straight up, and all the ones in our garden have a bit of flower of leaf directly above, apparently as some kind of camouflage.

I'm not sure what the tail is for - but they seem to use it for balance a bit. The end bit doesn't actually do anything - the spinnarets are just behind the back legs. I was thinking it might be some kind of Batesian Mimicry, but possibly not - I'm not aware of anything that looks even remotely like this spider.

I fed it a cockroach