Close-up of a cellar spider's cephalothorax, showing two groups of three clustered eyesKingdom:Phylum:Subphylum:Class:Order:Infraorder:Family:, 1850,Estimated of Pholcidae.Pholcidae, commonly known as cellar spider, daddy long-legs spider, granddaddy long-legs spider, carpenter spider, daddy long-legger, vibrating spider and skull spider, is a of first described by in 1850. It contains over 1800 species divided in 94 genera.The common name 'daddy long-legs' is used for several species, especially, but is also the common name for several other groups, including, which are but not spiders,. Contents.Appearance Pholcids are thin and fragile arachnids. The body (resembling the shape of a ) is approximately 2–10 mm (0.08-0.39 inches) in length, and the legs may be up to 50 mm (1.97 inches) long. Pholcus and Smeringopus have cylindrical abdomens and eyes arranged in two lateral groups of three and two smaller median contiguous eyes. Arrangements of eight and six eyes both occur in this family.

Spermophora has a small abdomen and its eyes are arranged in two groups of three without median eyes. Pholcids are gray to brown, sometimes clear, with banding or markings.Habitat Pholcids are found in every continent in the world except. Pholcids hang inverted in their messy and irregular-shaped webs. These webs are constructed in dark and damp recesses such as in caves, under rocks and loose bark, and in abandoned mammal burrows.

Pholcidae, commonly known as cellar spider, daddy long-legs spider, granddaddy long-legs spider, carpenter spider, daddy long-legger, vibrating spider and skull spider, is a family of araneomorph spiders first described by Carl Ludwig Koch in 1850. It contains over 1800 species divided in 94 genera. Some people call them flying daddy long-legs, others confuse them for giant mosquitoes. These frightening-looking insects are actually just harmless, winged creatures, known as crane flies.

In areas of human habitation pholcids construct webs in undisturbed areas in buildings such as attics and cellars (hence the common name 'cellar spider'). Behavior. Cellar spider vibrating rapidly in response to a threat Trapping The web of pholcids has no adhesive properties and instead relies on its irregular structure to trap prey.

When pholcid spiders detect prey within their webs the spiders quickly envelop prey with silk-like material before inflicting a fatal bite. The prey may be eaten immediately or stored for later. When finished they will clean the web by unhooking the prey and letting it drop from the web.

They are passive against humans.Threat response Some species of Pholcidae exhibit a threat response when disturbed by a touch to the web or entangled large prey. The arachnid responds by vibrating rapidly in a gyrating motion in its web. While other species of spider exhibit this behaviour, such behavior by the Pholcidae species has led to these spiders sometimes being called 'vibrating spiders'. There are several proposed reasons for this threat response. The movement may make it difficult for a predator to locate the spider or may be a signal to an assumed rival to leave. Only human cover. Vibrating may also increase the chances of capturing insects that have just brushed their web and are still hovering nearby.

If the spider continues to be disturbed it will retreat into a corner or drop from its web and escape.Diet Certain species of these spiders invade webs of other spiders to eat the host, the eggs, or the prey. In some cases the spider vibrates the web of other spiders, mimicking the struggle of trapped prey to lure the host closer. Pholcids prey on, and are known to attack and eat,. Pholcids may be beneficial to humans living in regions with dense populations as predation on Tegenaria may keep populations in check. Gait Pholcus phalangioides often uses an alternating tetrapod gait (first right leg, then second left leg, then third right leg, etc.), which is commonly found in many spider species.

However, frequent variations from this pattern have been documented during observations of the spiders' movements.Misconceptions There is a that daddy long-legs spiders have the most potent venom of any spider, but that their fangs are either too small or too weak to puncture human skin; the same legend is also repeated of the and, also known as 'daddy long-legs' in some regions. Indeed, pholcid spiders do have a short fang structure (called uncate due to its 'hooked' shape). Also have uncate fang structure, but are able to deliver medically significant bites.Possible explanations include: pholcid venom is not toxic to humans; pholcid uncate are smaller than those of brown recluse; or there is a musculature difference between the two arachnids, with recluses, being hunting spiders, possessing stronger muscles for fang penetration.

According to Rick Vetter of the at Riverside, the daddy long-legs spider has never harmed a human and there is no evidence that they are dangerous to humans.The legend may result from the fact that the daddy long-legs spider preys upon deadly venomous spiders, such as the, a member of the genus. To the extent that such entomological information was known to the general public, it was perhaps thought that if the daddy long-legs spider could kill a spider capable of delivering fatal bites to humans, then it must be more venomous, and the uncate fangs were regarded as prohibiting it from killing people.

In reality, it is able to cast lengths of silk onto its prey, incapacitating them from a safe distance. Mythbusters experiment During 2004, the television show tested the daddy long-legs venom myth in. Hosts and first established that the spider's venom was not as toxic as other venoms, after being told about an experiment whereby mice were injected with venom from both a daddy long-legs and a black widow, with the black widow venom producing a much stronger reaction.After measuring the spider's fangs at approximately 0.25 mm, Adam Savage inserted his hand into a container with several daddy-long-legs, and reported that he felt a bite which produced a mild, short-lived burning sensation. The bite did in fact penetrate his skin, but did not cause any notable harm. Additionally, recent research has shown that pholcid venom is relatively weak in its effects on insects.