Orb-weavers (Theridiidae) are, in terms of shape and coloration, an extremely diverse family of spiders. The vast majority have a pronounced pattern on the abdomen, while some are monochromatic. In terms of shape, color, or pattern, some orb-weavers bear a striking resemblance to spiders from other families, for example to baldahinarje (Lyniphiidae), cross spiders (Araneidae) or long-jawed spiders (Tetragnathidae). They differ from them by the small number of spines on the legs of orb-weavers.
The webs of orb-weavers are also highly variable in shape. From three-dimensional webs woven from irregularly interwoven threads for catching flying insects, to completely simple webs built from only a few threads. The capture threads can be attached to a substrate and many sticky droplets are exuded onto which a passing insect sticks, the thread tearing as the creature tries to free itself, and the hapless prey hangs in the air, or in the struggle for life becomes even more entangled in the spider's trap. Some species, however, have abandoned weaving webs and literally cast the silk thread onto their prey, for example onto an ant that comes too close to them. The captured insect is sucked dry by the orb-weavers, leaving only the outer chitinous exoskeleton remaining.
The courtship life of orb-weavers is also diverse. While some species do not place much importance on courtship and mating is quick, the males of other species devote themselves completely to the female and lure her by trembling her web. Some males of certain species even 'sing' to her, as they can signal in a similar way to crickets, by rubbing a toothed structure against a specially designed edge. This mode of signaling is called stridulation.
