Brazilian wandering spider
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P. bahiensis |
The Brazilian wandering spider (Phoneutria spp.) is an aggressive and highly venomous spider regarded by some as the most dangerous spider in the world. It is named as such because it was first discovered in Brazil, though this genus is known to exist elsewhere in South and Central America. This spider is a member of the Ctenidae family of wandering spiders.
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[edit] Phoneutria
Phoneutria spp. is actually a genus with five known similar species whose members are highly venomous and not reluctant to attack people who appear threatening. However, recent studies possibly indicate (but not with any irrefutable proof) that these spiders only inject venom in approximately one-third of their bites and may only inject a small amount in another third. The problem with this theory are the inaccuracies involved with absolute definitive identification of a particular subspecies. Thus the effects of the bites from these spiders are hard to determine when based on sketchy information or inaccurate identification of a subspecies.
The effects are reported to range from only a couple of painful pinpricks to a full-blown envenomation. In either case, people bitten by a Phoneutria or any Ctenid should seek immediate emergency treatment as the venom is possibly life threatening. The Phoneutria fera and nigriventer are the two most commonly implicated as the most virulent of the Phoneutria spiders. The Phoneutria not only has a potent neurotoxin, but is reported to have one of the most excruciatingly painful envenomations of all spiders due to its high concentration of serotonin.
Of the five species known, P. nigriventer and P. fera seem to be the ones to receive mention most frequently in mass-media publications. P.nigriventer species are responsible for most cases of venom intoxication in Brazil because this specie is commonly found in highly populated areas of Brazil, namely the South-eastern states: São Paulo, Minas Gerais, Rio de Janeiro and Espírito Santo. The P. fera is native to the northern portion of South America, especially the Brazilian Amazônia, Venezuela and French Guiana.
The Brazilian wandering spider is reputed to occasionally hide in clusters of bananas. As a result, any large spider appearing in a bunch of bananas should be treated with due care.
This spider is called the wandering spider because it wanders the jungle floor, rather than residing in a lair or maintaining a web. This attribute is another reason it is considered so dangerous. In densely populated areas, Phoneutria species usually search for cover and dark places to hide during daytime, and this may occur inside houses, clothes, cars, boots, boxes and log piles; thus generating accidents when near people.
Despite its reputation as the world's deadliest spider, there are multiple studies that argue its capacity for a fatal human envenomation. One study suggested that only 2.3% of bites (mainly in children) were serious enough to require antivenom.[1] However, other studies suggest it is the most dangerous or toxic spider in the world based upon toxicology studies. One of the most notable and thorough studies are presented in the book "Venomous Animals and their Venoms Vol. III" edited by Wolfgang Bucheral and Eleanor Buckley, and cleary demonstrate Phoneutria nigriventer's extreme toxicity in a table showing that the amount necessary to kill a 20gm mouse was only .006mg (intravenously) and .0134 subcutaneously as compared to Latrodectus mactans (Black Widow) at 0.110 and 0.2 respectively. The same study reports the death of two children killed by the same spider in Sao Sebastião (near San Paulo Brazil) identified as a Phoneutria, and identified by Bucheral. This demonstrates the fact that identification is key in the process of accurately associating a bite with the correct, offending species. The evidence, so far, clearly shows that both P. nigriventer and P. fera are extremely dangerous and one should not take any chances based on opposing studies of its toxicity to humans. There is no doubt as represented in the above mentioned study that credible, hard scientific, pharmalogical studies strongly suggest the danger of Phoneutria envenomation and ranks various species of the Phoneutria genus arguably as one of the world's most dangerous spiders.
[edit] Interesting Facts
The spider is called Brazilian because it was discovered and documented in Amazonia.
The antidote for its poison was developed by Carlos Chagas, in Brazil.
Spiderlings of this species eat flightless fruit flies and pinhead crickets, while adults eat crickets, other large insects, small lizards, and mice.
This spider is sometimes called the "banana spider" because it is often hidden among bananas shipped to the U.S.
The Brazilian wandering spider can grow up to 4-5 inches. Spiderlings can live in a clear plastic deli container with air holes and adults can live in a 5-to-10-gallon tank.
[edit] In fiction
The Fear from Metal Gear Solid 3: Snake Eater used the venom from the aforementioned spider to cover his crossbow bolts with it to fire at the player. (Additionally, it is not confirmed if it's the most potent poison in the game itself.)
Synthetic Brazilian Wandering Spider venom was also used as a murder weapon in an episode of CSI: NY.
[edit] Species
- Phoneutria bahiensis Sim & Brescovit, 2001
- Phoneutria boliviensis (F. O. Pickard-Cambridge, 1897)
- Phoneutria fera Perty, 1833
- Phoneutria nigriventer (Keyserling, 1891)
- Phoneutria reidyi (F. O. Pickard-Cambridge, 1897)
[edit] Footnotes
- ^ Bucaretchi F, Deus Reinaldo C, Hyslop S, Madureira P, De Capitani E, Vieira R. "A clinico-epidemiological study of bites by spiders of the genus Phoneutria". Rev Inst Med Trop Sao Paulo 42 (1): 17-21. PMID 10742722.
