![]() These include groups like the ground spiders (Gnaphosidae), huntsman spiders (Sparassidae), sac spiders (Clubionidae) and sun spiders (Corinnidae). Many other litter, bark and foliage hunting spiders use lie-in-wait ambush as well as active wandering strategies to catch their prey. However, as well as looking like a 'turd' the spider also secretes a chemical scent that makes it smell like one! Flies and butterflies that feed on dung (yes, some butterflies do this) are attracted to these 'dung' spiders, which ambush and eat them. Its body colour and shape resembles a drop of bird dung. A tropical Thomisid species, Phrynarachne decipiens, has gone about things a little differently. Their strong, spiny front legs allow them to grasp and hold the prey while it is bitten. Using sight, vibration and touch senses they target insects and other prey alighting or walking nearby - like flies, butterflies and bees, some of which may be considerably larger than the spider. Their body colours usually merge well with their background (flower frequenting species are capable of adjusting their body colour to suit), concealing them from both predators and prey. They sit in the open, on foliage ( Sidymella spp.), flowers ( Diaea spp.) or bark ( Stephanopis spp.). Many are ambush hunters like the flower or crab spiders (Thomisidae). ![]() Such spiders also have a surprising range of prey catching strategies. There are many other araneomorph spiders that no longer build snare webs. Two notable examples are the Bolas Spiders ( Ordgarius), another moth specialist, and Net -casting Spiders ( Deinopis). These involve simplification and modification of the orb web and highly specialised web handling behaviour. In such elongate webs, moths lose so many scale hairs while struggling to get free that they become stuck before they can roll out of the web.Įven more specialised prey capture strategies have evolved in other descendants of orb weaver lineages. However, some orb web weavers have evolved long, ladder-like orb webs. The body and wings of moths are covered in scale-like hairs that can be easily shed, and this often allows them to struggle free of a silk trap. For example, moths are a very abundant food source. ![]() Many of these web builders use silk enswathing and wrapping to subdue and 'package' their meal for immediate or later consumption.ĭespite its great success as an insect trap, the orb web has undergone some interesting specialisations. These included 'space webs', 3-D webs with a maze of threads that delay the prey long enough for the spider to enswathe it in silk or bite it knockdown webs combining a maze of lines above with a silk sheet below - the maze of 'knockdown' threads stop flying or jumping prey which fall onto the sheet below and also help keep the sheet clear of debris orb webs, with large, planar catching surfaces that are sticky, strong and stretchy and virtually invisible to flying insects sticky 'gum-footed' webs like that of the Redback Spider that catch walking prey and many others. Insects provide the vast majority of spiders' food and many web-based prey catching strategies evolved in response to this plentitude. These webs are effective for capturing walking and jumping prey but will also entangle flying prey like moths and flies. ![]() By contrast, Hammock Web spiders sit on the rock or wood substrate shielded by their hammock-like sheet web. Most of these webs are built out from a crevice retreat in a soil bank or tree trunk. The common Black House or Window Spiders progressively thicken their sheet webs with several silk layers - the shawl-like webs. They are made by primitive cribellate spiders like the Tasmanian Cave Spider, Hickmania troglodytes, and many modern spiders like the striped sheet web spiders ( Therlinya spp). The ancestors of today's araneomorph spiders used cribellate (wool-like) catching silk, probably in some form of a simple sheet web, to capture their prey.
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