Springtime, summertime, spidertime: The Australian two-spined spider

Spring and summer time is spider time.   

If you take the time to look around your garden from now on, you'll find that these useful little helpers are everywhere, taking advantage of the abundance of prey that comes with the warmer days.  

Some hunt on foot while others construct a web or a snare; the technology of silk and spatial spider memory is being studied, and they're slowly revealing the most surprising facts.  

There are spiders that recycle the protein of their silk, simply by eating it. A good example is the Australian two-spined spider (Poecilopachys australasia).   

This beast belongs to the orbweb spider family Araneidae and arrived in New Zealand, quite by accident, more than 50 years ago. It is a real stunner and probably the most common spider to feature on talkback radio: everybody that finds a female of this arachnid in their garden believes that an alien has invaded the quarter acre paradise.  

This spider occurs mostly on the North Island and top of South Island. 

The female colours are a vibrant yellow, dark red, and green, and the carapace or abdomen is punctuated by two distinct spines. They're about eight millimetres big. 

The puny male (three millimetres) literally looks like nothing, lacks the two spines, and is much smaller.   

From mid-summer onwards the small, brown males can be found – if you are lucky, that is! You can always identify them by their relatively large swollen "palps", which are appendages at the front of the body.  

Poecilopachys loves to live in citrus bushes or camellias; anything with sizeable, shiny leaves. During the day it sits motionless on the underside of a leaf, and despite its colours it can be pretty hard to find. At night she'll spin a large, rather incomplete, orbweb that acts as an aerial filter for flying insects. The preferred food is small moths.  

When the morning sun peeps over the horizon, the two-spined spider literally removes all evidence of her nocturnal web by hauling it in and devouring the silk, complete with some of the catch. The next evening the whole process starts all over again. 

The egg sac of this species is quite distinct: a spindle-shaped container made from a sturdy, mid-brown silk, suspended with fine strands between some leaves.   

When the spiderlings hatch they chew a neat round hole in the outer skin of the egg sac.  

As soon as they make their way out of their nursery, they spin a long strand of silk, allowing the wind to pick them up and transport them to other spots in the garden.   

Free ballooning! 

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