The band may be a lure for prey, a marker to warn birds away from the web, and a camouflage for the spider when it sits in the web. As orb-weavers age, they tend to have less production of their silk, many adult orb-weavers can then depend on their coloration to attract more of their prey. It is found in several genera, but Argiope – the yellow and banded garden spiders of North America – is a prime example. One feature of the webs of some orb-weavers is the stabilimentum, a crisscross band of silk through the center of the web. Some species of Gasteracantha have very long, horn-like spines protruding from their abdomens. ![]() The spiny orb-weaving spiders in the genera Gasteracantha and Micrathena look like plant seeds or thorns hanging in their orb-webs. Both genera of bolas spiders are highly camouflaged and difficult to locate. These get stuck on the globule and are reeled in to be eaten. The pheromone analog attracts male moths of only a few species. The globule is hung from a silken thread dangled by the spider from its front legs. Members of the genera Mastophora in the Americas, Cladomelea in Africa, and Ordgarius in Australia produce sticky globules, which contain a pheromone analog. Some orb-weavers do not build webs at all. Thus, the webs of orb-weavers are generally free of the accumulation of detritus common to other species, such as black widow spiders. ![]() Generally, towards evening, the spider will consume the old web, rest for approximately an hour, then spin a new web in the same general location. Most orb-weavers tend to be active during the evening hours they hide for most of the day. Many orb-weavers build a new web each day. This leads to a trade-off between the visibility of the web and the web's prey retention ability. Much of the orb-spinning spiders' success in capturing insects depends on the web not being visible to the prey, with the stickiness of the web increasing the visibility and so decreasing the chances of capturing prey. If the prey is a venomous insect, such as a wasp, wrapping may precede biting and/or stinging. Characteristically, the prey insect that blunders into the sticky lines is stunned by a quick bite, and then wrapped in silk. The third claw is used to walk on the nonsticky part of the web. The rest of the scaffolding follows with many radii of nonsticky silk being constructed before a final spiral of sticky capture silk. The spider secures the line and then drops another line from the center, making a "Y". The building of a web is an engineering feat, begun when the spider floats a line on the wind to another surface. Generally, orb-weaving spiders are three-clawed builders of flat webs with sticky spiral capture silk. Their webs are strikingly similar, but use a different kind of silk. ![]() The cribellate or hackled orb-weavers ( Uloboridae) belong to a different group of spiders. The family Arkyidae has been split off from the Araneidae. The long-jawed orb weavers ( Tetragnathidae) were formerly included in the Araneidae they are closely related, being part of the superfamily Araneoidea. Orb webs are also produced by members of other spider families. A framework of nonsticky silk is built up before the spider adds a final spiral of silk covered in sticky droplets. Araneid webs are constructed in a stereotyped fashion. With 3,067 species in 177 genera worldwide, Araneidae is the third-largest family of spiders (behind Salticidae and Linyphiidae). The family has a cosmopolitan distribution, including many well-known large or brightly colored garden spiders. Araneids have eight similar eyes, hairy or spiny legs, and no stridulating organs. The English word orb can mean "circular", hence the English name of the group. They are the most common group of builders of spiral wheel-shaped webs often found in gardens, fields, and forests. Orb-weaver spiders are members of the spider family Araneidae.
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