Is it true that the Daddy Long Legs spider has the most venomous bite of any spider but its mouth parts are too small to bite humans?

looney_tunes

The short answer is no. The long answer is more complex! The term Daddy Long Legs is used to describe three totally different arthropods: Pholcidae or Cellar door spiders (which are true spiders), the Crane Fly (insects) and harvestmen (arachnids, but not spiders). Pholcidae: "There is an urban legend stating that daddy long-legs spiders have the most potent venom of any spider, but that their chelicerae (fangs) are either too small or too weak to puncture human skin; the same legend is also repeated of the harvestman and crane fly, also called "daddy long-legs" in some locales. Indeed, pholcid spiders do have a short fang structure (called uncate). However, brown recluse spiders also have uncate fang structure, but are able to deliver medically significant bites. Either pholcid venom is not toxic to humans or there is a musculature difference between the two arachnids, with recluses, being hunting spiders, possessing stronger muscles for fang penetration. [5] In 2004, the Discovery Channel show MythBusters set out to test the daddy long-legs myth (season 1, episode 13 "Buried in Concrete"). After measuring the spider's fangs at approximately 0.25 mm (average human skin thickness varies from about 0.5mm to 4mm), the show's host was apparently bitten, although the bite produced little more than a mild short-lived burning sensation. This appears to confirm the suspicion that pholcids can penetrate human skin, but that their venom is practically harmless to humans. Additionally, recent research by Alan Van Dyke has shown that pholcid venom is actually relatively weak in its effects on insects as well[6]. According to the University of California at Riverside, the daddy long-legs spider has never harmed a human and there is no evidence that they are venomous to humans.[7] One reason why these spiders are said to be so dangerous could be that they regularly prey on other spiders, including the black widow (Latrodectus spp.), which itself can be dangerous to humans, with the reasoning that the preying spider must be even more venomous; which is incorrect. (Pinto-da-Rocha et al. 2007:4)" http://en.wikipedia.org/wiki/Pholcidae Harvestman: "An urban legend claims that the harvestman is the most venomous animal in the world, but possesses fangs too short or a mouth too round and small to bite a human and therefore is not dangerous. (The same myth applies to the cellar spider, which is also called a daddy longlegs.)[8] This is untrue on several counts. None of the known species have venom glands or fangs, instead having chelicerae.[9] The size of its mouth varies by species, but even those with relatively large jaws hardly ever bite humans or other large creatures, even in self-defense. The few known cases of actual bites did not involve envenomation, and had no lasting effect." http://en.wikipedia.org/wiki/Opiliones Crane Fly: There is an urban legend stating that the daddy long-legs spider has the most potent venom of any spider, and this same legend is attributed to crane flies where they commonly go by the name "daddy-long legs" (principally in the United Kingdom). However, both the daddy long-legs spider and the crane fly are in fact innocuous; the spider's venom is practically harmless to humans, and the crane fly is not venomous. The commonly confused harvestman, also known as daddy long-legs but which isn't a spider, is also not venomous." http://en.wikipedia.org/wiki/Crane_fly Dec 27 08, 4:47 PM

Boycie75

There is an urban legend stating that the daddy long-legs spider has the most potent venom of any spider, and this same legend is attributed to crane flies where they commonly go by the name "daddy-long legs" (principally in the United Kingdom). However, both the daddy long-legs spider and the crane fly are in fact innocuous; the spider's venom is practically harmless to humans, and the crane fly is not venomous. The commonly confused harvestman, also known as daddy long-legs but which isn't a spider, is also not venomous. http://en.wikipedia.org/wiki/Crane_fly#Venom Dec 27 08, 4:47 PM

zbeckabee

Their mouth is too small to bite humans. It feeds on small insects or the corpses of larger ones. It has a penis, which makes it different from spiders. In fact, the Daddy Longlegs is not technically a spider, although it is an arachnid. The problem with the 'Daddy Longlegs' is that the name is used for several kinds of animals, 2 of them arachnids: 1) The family Phalangiidae (a part of the opilionids [harvestmen], a different order than spiders) 2) a spider: Pholcus phalangioides Number one doesn't have poison glands. Number two has poison glands but as far as is known in the scientific world, nobody has ever been bitten by one of them. It's not sure if the poison has ever been investigated since there was no need for it." http://www.straightdope.com/columns/read/1447/is-a-daddy-long-legs-the-most-poisonous-spider Dec 27 08, 6:40 PM