some other content i found on the net, rather intresting...
Apparently the most venomous spider is the
Brazilian wandering spider (Phoneutria spp.).
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. Recent studies suggest that these spiders only inject venom in approximately one-third of their bites and may only inject a small amount in another third. The evidence, so far, clearly shows that both
P. nigriventer and
P. fera (on the photo) are extremely dangerous.
The
funnel web spider are other very venomous genus.
Atrax robustus (on the photo) and
Atrax formidabilis arguably are the most venomous and dangerous spiders in the world according with AFPMB.
The
widow spiders are very dangerous too. The venom is not as potent as the two genus above but the evidence show that there are comparable amount of deaths and health problems caused by these spiders. Relatively to the most of the spiders their venom is still very potent, (15 times more potent than that of the rattlesnakes; it is also reported to be much more potent than the venom of cobras and coral snakes). For
Latrodectus mactans the amount of venom necessary to kill a 20 gm mouse was 0.110 mg (intravenously) and 0.2 mg subcutaneously. 63 deaths were reported in the United States between 1950 and 1989. Prior to the development of antivenom, 5% of reported bites resulted in fatalities. On the photo
black widow (possibly
Latrodectus mactans) - one of the most dangerous in the genus.
Deadliest spiders!
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