The first problem encountered when trying to answer this question is the definition of the word "largest". By"largest" do we mean "longest", or "heaviest"?
When trying to answer this question do we take unsubstantiated reports into account, or do we only take into account verified scientific evidence?
It is also important to note at this point that there are exceptions to the rule. A record breaking length of any individual within a species cannot justify the entire species being labelled as giants, there are of course "freaks of nature" that are exceptions to the rule. So when answering what seems to be a simple question do we take record measurements of a species into account, or do we take the average size of any particular species in question?
There are only two possible candidates that could lay claim to the title of the world's largest snake. The Green Anaconda (Eunectes murinus) of central and tropical South America and the Reticulated python (Python reticulatus) of Asia. Both can be classified as giants. (At least the experts agree on this one)
The first contender for the title of largest snake is the Green Anaconda (Eunectes murinus). There are a number of unsubstantiated reports and claims of specimens exceeding 11 m (37ft) being found, but none of these claims could be verified and should be regarded with caution.
The average adult length for a Green Anaconda is between 5.3 m - 6.2 m (18 - 20ft) with the female always being much larger than the male of the species.
What is truly impressive is the sheer size (weight) of the Green Anaconda. Individuals weighing in at more than 220kg (485lbs) with a diameter of 30cm are not uncommon in this species.
The Reticulated python (Python reticulatus) may attain a maximum length of more than 9m (29ft). The longest reticulated python recorded was 10.05m (33ft). Despite its impressive length the record weight for a reticulated python is 145kg (320lbs), far less than the maximum weight of the Green Anaconda. As a result of its slender, less bulkier, build the reticulated python is a far more agile snake.
Although there may be disputes regarding which species of snake is the largest, there can be little argument as to which was the most colossal snake ever...
Coming in part 2!!!!!