By Jonathon Howard
I came across a spider the other day. It was crawling across the flyscreen that covers my back door. My guess is that it was looking for somewhere to escape the dry.
I recognised instantly as a spider belonging to the family Deinopidae, distinctive for its long stick-like body, spindly legs, and huge pair of forward-facing eyes that help it to see at night. The huge eyes are why these creatures are commonly called ogre-faced spiders.
Ogre-faced spiders have a unique way of catching their prey. When at rest, the spider hangs from vegetation with its head downwards, its long body and front and back legs held together on each side, so it looks like a stick. The spider also assumes this position when it is hunting with its deadly secret weapon – an elastic net that it holds with its four front legs.
This net can be stretched out wide to envelop a passing insect. In order to have an aiming point, the spider often drops splashes of its white faecal droppings onto the leaf or bark substrate over which it is poised. So when an insect walks across this ‘target’, the spider plunges its net downward and envelops it prey. These spiders hunt at night, feeding on ants, beetles, crickets and other spiders.
Orge-faced spiders are common in bushland and gardens. By day they hide, stick-like, among foliage. By night they build beautiful, bluish-white, little nets about the size of a postage stamp.
Their excellent night-vision makes them keen night-time hunters. Indeed, its front facing eyes are so large in comparison to the other six eyes that the spider seems to have only two eyes. It enables the spider to gather any available light more efficiently than the eyes of cats and owls. And perhaps what fascinates me most, is the fact that its eyes don’t have irises, as such its light sensitive membranes are rapidly destroyed each morning and ogre-faced spider have to grow a new large area of light-sensitive membrane each day.
These spiders are not considered dangerous. So I moved it back into the garden and wished it happy hunting.