![]() Orb webs in "non-orb" weaving ogre-faced spiders (Araneae: Dinopidae): a question of genealogy. Note on the construction of the net and sperm web of the cribellate spider Dinopis subrufus (Koch) (Araneidae: Dinopidae). The biology of two Australian species of dinopid spider. No interactions with humans or threats to net-casters have been identified. In a few weeks they start building their own tiny nets. The dark brown spiderlings emerge in spring and look like a cloud of little anchors (narrow body and extended front legs) hanging in silk lines above the egg sac. It is also known as the skull spider, since its cephalothorax is said to resemble a human skull. The sacs are suspended on vegetation and disguised with twig and leaf litter detritus. Pholcus phalangioides, commonly known as the cosmopolitan cellar spider, long-bodied cellar spider or one of various types called a daddy long-legs spider, is a spider of the family Pholcidae. ![]() The egg sacs are round balls, 9-10 mm in diameter, covered with a tough, closely woven layer of salmon-brown silk flecked with black. The male attaches a mating thread to the female's net support lines and jerks it to entice her onto it for mating. Net-casting spiders mature in summer, with mating and egg-laying taking place into autumn. The image is focussed onto a large, light-receptive retinal membrane (which is destroyed at dawn and renewed again each night). Their compound lenses have an F number of 0.58 which means they can concentrate available light more efficiently than a cat (F 0.9) or an owl (F 1.1). The Net-casting spiders' large eyes provide outstanding low-light night vision. Prey as large as male trapdoor spiders and gryllacridid wood crickets are taken. Prey animals include cockroaches, ants, spiders and even moths - net-casters seem sensitive to air currents and will lunge the net towards aerial prey. While eating its catch, the spider may start making a new net for its next meal. The clinging silk net envelopes the insect, which is then rapidly bitten and wrapped. When an insect passes over the white target spots, the spider opens the stretchy web to two or three times its resting size and lunges it downward over the unsuspecting prey. The spider hangs head down from a trapeze of silk, holding the net in its front pairs of legs and there it waits, its enormous eyes watching for prey movement across the white aiming spots. After spinning its web the spider deposits some spots of white faeces on this surface to act as aiming points. a broad leaf, a tree trunk or even a house wall). These little nets are made among low vegetation, usually above a surface across which prey animals are likely to walk (e.g. Short-bodied cellar spiders may carry a little. At night they build a rectangular, postage-stamp-sized web, made with wool-like, entangling silk threads. The female long-bodied cellar spider typically produces three egg sacs during her lifetime, each one holding between 13 and 60 eggs. Its eyes are able to gather available light more efficiently than the eyes of cats and owls, and are able to do this despite the lack of a reflective layer ( tapetum lucidum) instead, each night, a large area of light-sensitive membrane is manufactured within the eyes, and since arachnid eyes do not have irises, it is rapidly destroyed again at dawn.The prey-catching method of net-casting spiders is unique. At night, it emerges to practice its unusual prey capture method on invertebrate prey. In Florida, Deinopis often hangs upside down from a silk line under palmetto fronds during the day. They are distributed through tropics worldwide from Australia to Africa and the Americas. This family also includes the humped-back spiders ( Menneus). The name refers to the perceived physical similarity to the mythological creature of the same name. Ogre-faced spiders ( Deinopis) are the best known genus in this family. These eyes are larger than the others, and sometimes makes these spiders appear to only have two eyes. The posterior median eyes have excellent night vision, allowing them to cast nets accurately in low-light conditions. These unusual webs will stretch two or three times their relaxed size, entangling any prey that touch them. It consists of stick-like elongated spiders that catch prey by stretching a web across their front legs before propelling themselves forward. Deinopidae, also known as net casting spiders, is a family of cribellate spiders first described by Carl Ludwig Koch in 1850.
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