The worlds most venomous spider? End-all-be-all-topic.

[Haplopelmatic]

1. Should be Latrodectus mactans

2. Most likely Hadronyche infensa or H. formidabilis. Possibly Phoneutria fera or P. nigriventer.

3. Phoneutria ssp. I would say. And very few per year.

4. Not sure, maybe Loxoscelus ssp.

However, you must consider the nature of the spider, closeness to humans, willing to bite, venom potency and venom yield per bite.

/Lelle

I agree on all of the above statements, except the first. As far as I am informed, the spider with the most potent venom is L. geometricus. The IV LD-50 dose for L. geometricus is 0,31-0,51 ug/g in mice. Whereas the potency of L. mactans is around 1,50-2,50 ug/g using same test subjects and method of administration.
As I see it, LD-50 tables are the most scientific and only way of determining the toxicity of a creature. As long as we're talking drop-for-drop potency that is.

Great topic by the way!

/Cheers!

 

[kyle_de_aussie]

I guess we will just have to agree to disagree on this one ive researched a lot one these guys and they are marked down everywhere as THE MOST VENOMOUS SPIDER THERE IS IN THE WORLD
:razz: :razz: :razz:
PEACE OUT
KYLE

 

[Sheri]

I dont know where u got that information from mate but i live in australia and its common knowledge that atrax robustus is the most venomous no offence dude but maybe you should go check that info again Hadronyche infensa and Hadronyche formidabilis arent as venomous as atrax robustus thats a fact

On this site it clearly says that Atrax formidabilis is more potent, both male and females, than Atrax robustus, male. Additionally, it still doesn't claim that A. formidabilis is the most potent, but asserts that it is "near to the most dangerous in the world."

I think you might be getting confused with the difference between actual drop for drop venom toxicity, and the human fatality rates, which are entirely different and depend on proximity rather than the chemical makeup of a venom.

Statistically, A. robustus may post a greater threat, but that has little to do with venom potency.

 

[Crotalus]

I dont know where u got that information from mate but i live in australia and its common knowledge that atrax robustus is the most venomous no offence dude but maybe you should go check that info again Hadronyche infensa and Hadronyche formidabilis arent as venomous as atrax robustus thats a fact

Well you need to get updated then. I got the information from the australian Steve Nunn, who got it from Dr. Robert Raven - I assume those two are familar to you.
No offence taken.

/Lelle

 

[Crotalus]

clearly says that Atrax formidabilis is more potent, both male and females, than Atrax robustus, male. Additionally, it still doesn't claim that A. formidabilis is the most potent, but asserts that it is "near to the most dangerous in the world."

Formidabilis is transfered to Hadronyche. The only species in the genus Atrax is A. robustus.

/Lelle

 

[El Johano]

I dont know where u got that information from mate but i live in australia and its common knowledge that atrax robustus is the most venomous no offence dude but maybe you should go check that info again Hadronyche infensa and Hadronyche formidabilis arent as venomous as atrax robustus thats a fact

"Common knowledge" is not always the same as the truth. Lelle is right about H. formidabilis being more venomous than A. robustus. Because bites from A. robustus is far more common than from other funnelwebs the public perception may be that it is the most venomous.

It is also "common knowledge" in Australia that the white tailed spiders (Lampona murina and others) cause necrotising arachnidism similar to brown recluse bites. However it has been shown in a recent study of 130 bites that such symptoms are not associated with bites from white tailed spiders.

 

[kyle_de_aussie]

"Common knowledge" is not always the same as the truth. Lelle is right about H. formidabilis being more venomous than A. robustus. Because bites from A. robustus is far more common than from other funnelwebs the public perception may be that it is the most venomous.

It is also "common knowledge" in Australia that the white tailed spiders (Lampona murina and others) cause necrotising arachnidism similar to brown recluse bites. However it has been shown in a recent study of 130 bites that such symptoms are not associated with bites from white tailed spiders.

Well if its so untrue then the books ive read and the sites that say there the most venomous are wrong sorry dudes i beg to differ. show me proof and il check it out but as far as what ive read seen on sites and learnt about i still think atrax robustus is the most venomous of all spiders and i beleive im right prove me wrong give me a link to the place where the information is and il retract all what ive said if im wrong

 

[Sheri]

Formidabilis is transfered to Hadronyche. The only species in the genus Atrax is A. robustus.

/Lelle

Yeah, I kinda figured that out as I went along.

 

[Sheri]

Well if its so untrue then the books ive read and the sites that say there the most venomous are wrong sorry dudes i beg to differ. show me proof and il check it out but as far as what ive read seen on sites and learnt about i still think atrax robustus is the most venomous of all spiders and i beleive im right prove me wrong give me a link to the place where the information is and il retract all what ive said if im wrong

Did you not check the link I gave you?

Wow dude. You know, I've never seen the earth from space, but I'm still pretty sure I'll go with the current data that says its not flat. :wall:

 

[kyle_de_aussie]

Hi people i did a bit of checking around not in books on the web and sorry about that sherri i missed that link you posted the first time but i did go to it and a lot of other sites with recent info on this subject and it seems you guys are right sorry for doubting people i really thought that spider was the most venomous theres a lot of sites that still say it is to and books but i expect they need to be updated after reading what i have on the site sherry posted the link for and a few other sites sorry bout that people

 

[kyle_de_aussie]

Did you not check the link I gave you?

Wow dude. You know, I've never seen the earth from space, but I'm still pretty sure I'll go with the current data that says its not flat. :wall:

UM alright then

 

[JJJoshua]

Has anyone mention Sicarius, the six eyed sand spider? From what I've read it's venom is pretty dangerous as well.

Now with venom, are we talking how deadly it is, in terms of how many death a year it causes, or potency of the venom.

I would say A. robustus is one of the most deadly, while other species may possess more potent venom, their proximity to humans makes them less deadly.

I agree with Haplopelmatic, in that we should only compare venom potency through the LD-50 tables.

And world's most venomous spider? Does this mean the spider that injects the most venom??

ven·om·ous
adj.
1. Secreting and transmitting venom: a venomous snake.
2. Full of or containing venom.

All spiders are venomous, so the one that secretes or transmits the most venom, would be the most venomous?

Correct me if I am wrong.

 

[El Johano]

I agree with Haplopelmatic, in that we should only compare venom potency through the LD-50 tables.

The problem with LD-50 is that it is based on rats or mice, not humans. The Australian funnelwebs for example are very dangerous to primates and arthropods but not deadly to most other mammals. Therefore they have a rather high LD50 despite being very venomous.

 

[orcrist]

Since Phoneutria is a wellknown spider in the countries where this genus can be found I dont think they mistake a tarantula for a Phoneutria. What do you base this on? Its more a misunderstanding that once thought the european wolf spider, Lycosa tarentula, is supposed to be dangerous that created the myth that theraphosids are dangerous to humans.






/Lelle

My grandpa told me a story about his brother, who worked on a ship that carried all sorts of goods from S. America. One time, they were unloading some tropical fruits, and a large brown spider scurried out and bit a S. American hand on the hand. the man immediately crushed the spider and then quickly chopped his own hand off with a large knife that was nearby. My Grandpa's brother had to cauterize the wound. The guy WAS from the phoneutria area, so he knew what kind of spider it was, and he called it a tarantula. The majority of people in that area are not concerned with learning the difference between a phoneutria and a tarantula, but they do know that the world calls pretty much any big spider a tarantula.

 

[Venom]

I don't know if this has been brought up before or not, but could someone tell me what in the world "drop for drop" potency is supposed to mean?

Doesn't that just mean which venom has the highest toxic effect in the same volume of venom ( i.e. lower LD50 numbers ), and in that case, wouldn't a Hadronyche sp. have the most toxic venom "drop for drop," instead of a Latrodectus?? This term just confuses me.

 

[DR zuum]

According to the Guinness Book of Records the world’s most venomous spider is the Brazilian wandering spider (Phoneutria nigriventer).

This spider is believed to have the most active neurotoxic venom of any living spider. Its venom is so potent that only 0.006mg (0.00000021oz) is sufficient to kill a mouse.

Would Guinness be incorrect in this?If they are known for anything its being tops at validation before putting it in one of thier books.I watched a program on the wandering spiders and australian funnel webs on tv once,it too gave the title to the Brazilian wandering spider.So who volunteers for a test Crotalus?

 

[bugsnstuff]

This spider is believed to have the most active neurotoxic venom of any living spider. Its venom is so potent that only 0.006mg (0.00000021oz) is sufficient to kill a mouse.

Would Guinness be incorrect in this?If they are known for anything its being tops at validation before putting it in one of thier books.I watched a program on the wandering spiders and australian funnel webs on tv once,it too gave the title to the Brazilian wandering spider.So who volunteers for a test Crotalus?

But the LD50 of Latrodectus mactans is 0.0009mg, so going on LD50 figures it has the more potent venom

 

[El Johano]

This spider is believed to have the most active neurotoxic venom of any living spider. Its venom is so potent that only 0.006mg (0.00000021oz) is sufficient to kill a mouse.

Then that is not LD50. LD50 is the amount of venom injected when half of the animals in the experiment dies.

But the LD50 of Latrodectus mactans is 0.0009mg, so going on LD50 figures it has the more potent venom

Is that intravenous, subcutaneous, intraperitoneal? Is it per kilo, gram or some other measurement? What kind of experiment animals where used, mice, flies or maybe humans?
As I've already pointed out this is the problem with LD50, it only gives a value that is comparable with other LD50 values where the same type of administration and animals has been used.

 

[Crotalus]

Would Guinness be incorrect in this?If they are known for anything its being tops at validation before putting it in one of thier books.

Guinness is not always so correct no. I wouldnt use that book for reference unless its for checking up the tallest man maybe ;-)

/Lelle

 

[DR zuum]

Guinness is not always so correct no. I wouldnt use that book for reference unless its for checking up the tallest man maybe ;-)

/Lelle

Thats why i had a question mark behind it.But they've called it,and since they are the world accepted record book it's now up to someone to dispute it,go for it.The program i watched,i believe it was on discovery,not that they are perfect no one is, but its been a long while so i may be wrong on where i saw it,also gave the title to the wandering spider.

Then that is not LD50. LD50 is the amount of venom injected when half of the animals in the experiment dies.

Really ?

But the LD50 of Latrodectus mactans is 0.0009mg, so going on LD50 figures it has the more potent venom

I dont just take LDL'S as accepted and written in stone,was every sample taken from a specimen the same in toxicity?Were multiple tests run or just one on one group to establish the LDL?We were running tests here on LDL involving certain mushroom toxins using mice,we didnt run just one test group we ran multiple test groups guess what?

The LDL varied wildly from group to group using the same dosage and delivery method in multiple tests on mice.So before i'll accept that LDL, i'd be wanting to see that info,just as you posed the question on delivery and test subjects El Johano,were multiple tests run and test subjects run? Or did they just use 2 mice or 10 mice and proudly proclaim EUREKA !! :worship: Crotalus you have specimens of a wandering spider species,the very one cited i believe.Get a 100 gal tank, 2 male mice 25 females,you'll soon have all the test subjects you need,for a conclusive study post your LDL findings see if they match.

Somebody else with Latrodectus mactans specimens and Atrax robustus specimens, do the same,if you really want the question answered,if there really is a clear cut answer?There may not be one.But as it stands accurate or inaccurate the wandering spider holds the title,disprove it gentlemen. :clap:

http://www.directory.co.uk/Most_Venomous_Spiders.htm

For some reason the guinness link wont work,a search on guinness book of records most poisonous spider should take you to the links it took me to.