The St. Andrews Cross spider (Argiope kiyserlingi) is a medium-sized, pretty
orb weaving spider. It has two bright yellow to white stripes across its
abdomen, and has a dark golden-olive background colour. It holds its legs in
four pairs, forming a cross, hence its name.
There are several different morphs of the same species, with some in New Guinea,
and our native Australian ones. There is also a different, but closely related,
species, Argiope mangal, in Europe and America, where they are called the Black
or Yellow Argiope.
These spiders live in the bush or in peoples gardens, where they are more
common in summer. The female of this species builds a large orb web, and also
makes white cross markings, called stabilimentum, in the middle of the web. The
male is only about 5 mm long. These spiders are common throughout Australia,
including Tasmania. The St. Andrews Cross is usually non-aggressive, and there
have been no reported instances where a human has become seriously ill after
being bitten by them. Most likely, the worst consequence would be the fright
from the spider crawling over you!
The eggs are laid in a silk egg sack, which is normally put in leaves or twigs
near the mothers web. When the little spiders hatch, they make their webs with
a white disk in the middle, then add the cross as they get older. When they are
fully grown, they only make the cross in the web.