The debate of what are the most venomous snakes is one that occupies a disproportinate amount of time, it is of course purely academic... dead is dead.

However, since the questions arise so often, it is useful to have a list of the available data and sorted by route of injection. This of course greatly influences the relative toxicity.

One thing to keep in mind is that these sort of lists are not all inclusive and should not be taken as absolute rankings. Many snakes were not analysed by all four of the methods. The inland taipan (Oxyuranus microlepidotus, other common names formerly used were fierce snake and western taipan), the worlds most toxic snake , is not on a couple of the lists simply because it was not tested by those methods. The most commonly tested methods are subcutaneous and intravenous injections of mice. Subcutaneous is the most applicable to actual bites. Only large Bitis or extremely large Bothrops or Crotalus specimens wouls be able to deliver a bite that is truly intramuscular. IV injections are extremly rare in actual bites.

The murine model gives a reasonable indication of human toxicity but is not extact. By looking at all four lists, a fair idea of the relative toxities can be formulated.

Venom yield must also be considered. For example, Pseudonaja textilis (Eastern brown snake) is around two and a half time more toxic than Oxyuranus scutellatus (Coastal taipan) but the coastal taipan injects up to twenty to thirty times more venom. Thus, the net result it the coastal taipan injecting eight to twelve times more lethal doses than the eastern brown snake.

The LD50s are compiled from available literature. Where the same expirement was done by different labs, the results were averaged. (publication list will be up shortly)

Notes regarding taxonomy are also included off to the side, this is courtesy of Dr. Wolfgang Wuster who has stated the following:

"Many toxinologists have absolutely no idea what snakes their venoms came from. If you go through the toxinological litterature, you will find a vast selection of outdated, inappropriate, misleading or even totally contrived or invented names. I did a survey a while ago, in which it came out that 50-75% of the venoms of certain groups (Asiatic cobras and Echis) could not be confidently be assigned to one of the currently recognised species.

I bet that a fair few of the LD50s in Bryan's list are also from species other than that stated (not Bryan's fault, of course). This is a big problem in toxinology, which will persist until toxinologists can be persuaded to pay some attention to snake systematics, and furnish all the necessary information in their papers (in particular, locality of origin of specimens; also, specimens used for these studies should be deposited in museums so that their ID can be confirmed if necessary)."