I recently chanced upon a curious fluorescence out the corner of my eye, beneath the movement of a small black invertebrate. Upon closer inspection, I was delighted to see the Northern Jewelled Spider (Gasteracantha fornicata), weaving its fluorescent green egg-sac.
For many years I had wondered which spider was responsible for the moss-mimicking green pillows woven onto the surfaces of rainforest trunks or even more discretely beneath the underside of rainforest leaves. Not only was I impressed with their colour (as far as silk production goes), but they also seemed to be highly regarded by many rainforest birds in the camouflaging of their nests.
This two-dimensional wheel-web-weaving spider, also known as the Spiny Spider, was amongst the first collected by Sir Joseph Banks in 1770, when the Bark Endeavour was beached along the river that would become so named, in the heart of the Guugu Yimidhirr homelands in 1770.
The disruptive colouration and a surrounding feature of silk-thickenings, called stabilimenta, increase visibility in ways that increase attractiveness to the compound eyes of flying insects. The Northern Jewelled Spidere increases the uptake of food by increasing visibility.
