There are certain physiological limits in nature. For example, insects can only grow to a certain size due to the fact that too large and nerve impulses would become to slow for proper functioning. Another problem, one that insects share with spiders is the exoskeleton which limits size.
Spiders have another problem, and that is their respiratory system. For example, in tarantulas and certain other spiders have a book-lung respiratory system. The book-lung is an organ located on the abdomen of a spider, and is responsible for oxygen transference. it only works up to a certain size organism. If the spider becomes too large, the book lung becomes insufficient in carrying oxygen.
That said, through a combination of a book-lung and trachea, some modern spiders have gotten around this problem and as a result have an increase in blood flow, speed, stamina and size. But the question remains, how big is the upper limit?
Unless of course, evolution found a way for a new kind of spider, or perhaps an old kind of spider, and has develop a unique system that can account for a giant, maybe even the J’ba Fofi of the Congo, a 4 feet across kind of spider.
I had heard the stories myself when I was trying to put a Mokele-mbembe expedition together years ago, but honestly I heard a lot of things about what awaits in the Congo.
One of the earliest stories was from Uganda in the 1890’s, when an English missionary by the name of Arthur Simes ventured to Lake Nyasa. He claimed that a couple of his native porters became entangled in a web, and two giant spiders came out to attack the porters, and since this isn’t Syfy channel, nobody was eaten, but they were bitten. The result was not great, swelling of extremities, fever and eventually death. The spiders were described as 4 feet across and resembling tarantulas.
Fifty years later, and down the road into the Congo another famous sighting occured to a British couple driving. They initially thought it was a cat crossing the road, when they realized it was a spider between 3 to 5 feet in circumference.
Since then, you get stories here and there, mostly from native who claim that they were once much more abundant but know very rare, but still very dangerous.
Most of the descriptions come from Pygmies that live a little further out in the jungles. They describe them as around 4 feet in circumference, usually brown with some purple.
They behave very much like tarantulas, look like tarantulas, only bigger, and build web nests that are similar to tarantulas. They prey upon birds and small monkeys, and have been known to attack man if the opportunity presents itself. Their range seems to go from Uganda and the Central African Republic to Cameroon and both Congos.
There are also some sightings of a similar specie in Vietnam and especially in Venezuela which I’ll address in a future article,.
Physical description and behavior seem to point to a undiscovered tarantula relative, just bigger at the upper limit of what’s possible it seems.
Tarantulas are members of the Theraphosidae family with approximately 900 species worlwide. The largest, officially is the Goliath which is a foot across, a far cry from the J’ba fofi. There are 50,000 species of spider on the planet, with an estimated 200,000 more to be discovered, according to scientific estimations, and perhaps within that number a very large spider, 4 feet across and mean man, mean.