The male constructs a mating thread within the web, onto which it attracts a receptive female by vibrating the thread. One or more males sit in the upper parts of the web - some may be missing legs, survivors of encounters with unreceptive females. Mating occurs from summer to autumn and can be hazardous for the small male St Andrew's Cross Spiders. These measures don't always succeed, as indicated by empty, damaged webs and the presence of these spiders as food in the mud cells of wasps. When threatened, the St Andrew's Cross Spider responds either by dropping from the web or shaking it so vigorously that both spider and stabilimentum become a blur, confusing its attacker. These are usually secured by silk wrapping into a neat parcel before being bitten - although smaller prey may be bitten first. The prey of the St Andrew's Cross Spider includes flies, moths, butterflies, bugs and bees. The St Andrew's Cross Spider is found in eastern Australia in habitats ranging from rainforest margins to open forest and heathland (Queensland, New South Wales, Victoria). Another possibility is that the stabilimentum advertises a warning to predators like birds to stay away - after diving through the sticky web, the effort required to clean silk off plumage may deter birds from trying again. However, the variability of the shape of the cross decoration (a complete cross a partial cross with from one to three arms or sometimes absent altogether) could make web recognition confusing for the predator. The silk decoration could also make the web and its owner more obvious to day-active predators like birds and wasps. ![]() If the stabilimentum silk attracts insects it may increase the web's prey catching efficiency. ![]() Such light is attractive to flying insects, which use it to locate food sources like flowers and to navigate through openings in the vegetation. The ribbon-like silk reflects ultra-violet light strongly. At first thought to strengthen or 'stabilise' the web, more recent ideas associate it with capturing prey or avoiding predators. The role of the cross-like web decoration, called the stabilimentum, has long been a puzzle. The St Andrew's Cross Spiders build medium-sized orb webs, occupied day and night, on low shrubby vegetation.
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