Austracantha minax, from family Araneidae, is commonly called the Spiny, Jewel or Christmas Spider. It's a rather cute and fearless little thing, hanging in its web on fences or bushes day and night.
An up close view of the Spiny Spider's 12mm egg sac
The upper-side of the abdomen has a smooth enamelled appearance in black and white patterns with six bulky spines, while the under-side is yellow and black. Although pattern design and colour can vary slightly, the distinctive shape can not be confused with any other spider, making indentification easy.
When disturbed, it will run up its web to shelter on short stout orange legs, looking quite comical.
According to CSIRO, the Spiny Spider is found in Queensland, NSW and Victoria, and is at home in shrubby woodland.
I have seen this spider in areas of native bushland, but it is more common in gardens and amongst roadside weeds in my area. It can build a web of simple haphazard structure of a few supporting silk strands, or a neat orb web. Massive congregations of Spiny Spiders with overlapping webs are common amongst roadside vegetation.
Spider catches fly
The second picture illustrates the egg sac of the Spiny Spider that is attached to vegetation or structures close to the web. Web silk is thick, white and easily noticed.
The eye configuration is two rows each of 4 eyes, though this is difficult to distinguish from the image below. Like most spiders, they are not aggressive, and will run for cover if disturbed.
Legs tucked up in an attempt to hide when disturbed
I have found this delightful little spider coated in ice crystals in mid winter in my garden, as well as hanging in full 40-plus degree summer sun, so it is a hardy creature indeed. I have not seen Willy Wagtails or other birds feeding on them, so perhaps they taste nasty. Watch them scurry up their web on short fat orange legs carrying a bright spiky body - they're like charming little cartoon characters!