Hanging face-down in its web, like all spiders, Sydney Out Back spotted this St Andrew’s Cross Spider Argiope keyserlingi at North Head reserve; easily recognisable due to a zig-zag pattern (called a “stabilimentum” that resembles a cross) dissecting the web’s centre.
As Sydney Out Back shared the story of the St Andrew’s Cross Spider on a recent tour to North Head, our guests were most surprised to learn that its stabilimentum (the “cross” that was originally thought to stabilize the web) reflects ultra-violet light that attracts flying insects! Too clever.
In this picture, taken by Sydney Out Back, a female (averaging 10 – 16mm in size) waits day and night with legs in pairs, aligned with her zig-zag pattern, in a medium-sized orb web hung lower in the bush at North Head reserve – hoping for flying insects that she can wrap into a silk parcel for dinner later; insects including bugs, bees, flies, butterflies, dragonflies, cicadas and moths.
While orb spiders like the St Andrew’s Cross Spider rarely bite, its bite is painful and only requires medical attention if pain persists, or the wound becomes inflamed or infected. Best not to touch.
A St Andrews Cross Spider at North Head reserve. Photo: D.Cave for SydneyOutBack.com.au