Spiders might exist that have crawled out of nightmares. They're called the "J'ba FoFi" (giant spider, pronounced ch-bah foo fee) in Central Africa.
Many people might define a giant spider as one that's bigger than their hand. Some may think bigger and envision the horrifying Goliath 'bird eating spider' that dwells in the darker corners of the ancient Amazon rain forest. That eight-legged terror spans a whopping 14-inches.
Unfortunately, those people aren't thinking big enough.
The size of the Congolese Giant spider-when its legs are included-is said to be up to five feet across.
According to cryptozoologists (researchers that investigate unknown creatures that have not been recognized by orthodox science), most of the J'ba FoFi dwell in the Congo. Natives tell stories of the giant web-nests the spiders build, similar to a trap-door spider.
Most of the many anecdotal tales describe the spiders digging a shallow tunnel under tree roots and camouflaging it with a large bed of leaves. Then they create an almost invisible web between their burrow and a nearby tree, booby-trapping the whole thing with a network of trip lines. Some hapless creature—soon to end up on the menu—will trip the line alerting the spider. The victim will be chased into the web. This predatory entrapment is similar to some species of tarantula.
Presumably, the J'ba FoFi eggs are a pale yellow-white and shaped like peanuts. Native claim the hatchlings are bright yellow with a purple abdomen. Their coloration becomes darker and brown as they mature.
Some of the natives indigenous to the regions in the Congo where the J'ba FoFi has been seen assert that the spider was once quite common, but has become very rare.
Other than the testimonies of natives, the fullest account by Westerners appears in a cryptozoological book by George Eberhart. On page 204, Eberhart relates the terrifying experience of an English couple traveling through a jungle region of what is now called the Congo:
"R.K. Lloyd and his wife were motoring in the Belgium Congo in 1938 when they saw a large object crossing the trail in front of them. At first, they thought it was a cat or monkey, but they soon realized it was a spider with legs [spanning] nearly 3 feet [across]." 
Famous naturalist and cryptozoologist, William J. Gibbons, has hunted for what some think may be a living African dinosaur called Mokele-mbembe. On his third expedition in search of the creature he came upon natives who related their experiences with giant spiders. He shared his experience with readers upon his return to Canada:
"On this third expedition to Equatorial Africa, I took the opportunity to inquire if the pygmies knew of such a creature [giant spider], and indeed they did! They speak of the Jba Fofi, which is a "giant" or "great spider." They described a spider that is generally brown in color with a purple abdomen. They grow to quite an enormous size with a leg span of at least five feet. The giant arachnids weave together a lair made of leaves similar in shape to a traditional pygmy hut, and spin a circular web (said to be very strong) between two trees with a strand stretched across a game trail."
This is exactly the same description that other researchers have heard. Although the spider seems to have been spotted mostly in the Congo, there are reports of the same—or similar—spiders inhabiting Uganda and the Central African Republic.
"These giant ground-dwelling spiders prey on the diminutive forest antelope, birds, and other small game, and are said to be extremely dangerous, not to mention highly venomous," Gibbons states. "The spiders are said to lay white, peanut-sized eggs in a cluster, and the pygmies give them a wide birth when encountered, but have killed them in the past. The giant spiders were once very common but are now a rare sight."
Many of the natives describe the spiders as once being numerous, but now a vanishing species. Encroachment by civilization in the form of rain forest being converted to farming may have driven the spiders from their natural habitats.
[Although their numbers are dwindling] they are still encountered from time to time. The Baka chief, Timbo, casually mentioned to us that a giant spider had taken up residence in the forest just behind his village in November 2000, when I and Dave Woetzel from New Hampshire had visited him! He did not think that we would have been interested in the creature as our interest was focused on Mokele-mbembe at the time! Valuable evidence had eluded us."
Cryptozoologists—like any other researchers—sometimes only get the information they specifically ask for!
If these giants do indeed exist, their physiology is puzzling. As some entomologists have rightly pointed out, spiders of that size would have to overcome the limitations of their exoskeletons. In addition to that hurdle, many of the more primitive arachnids have a primitive book-lung respiratory system. Modern spiders, however, often have a trachea and book-lungs. That combination allows for a smaller heart, more efficient blood flow and greater speed and stamina. If the Congolese giant spiders exist, they would most likely have both trachea and book-lungs. 
"On questioning our group of six Baka guides," Gibbons narrative continues, "they have all seen these spiders at one time or another and state that they are quite capable of killing a human being. According to the Baka (and the Bantu hunters who have encountered them) the giant spiders were once surprisingly common and would often construct their lairs very close to human villages. They have become quite rare now thanks mainly to the deforestation of Central Africa, but my guess would be that they are still to be found in numbers in the vast and still untouched forests of the former [Belgian Congo or Zaire] where the Lloyds encountered one in 1938." 
Gibbons knew the Lloyd's personally and adds that Mr. Lloyd tried to get a photo of the spider while Mrs. Lloyd was so stricken with fear all she wanted to do was return to their home in Rhodesia.
Other stories of giant spiders abound. Some of the stories are little more than spotty tales told in the villages of unnamed missionaries whose porters were killed by giant spiders.
An English missionary named Arthur Simes related an incident that occurred in Uganda during the 1890s. While trekking near the shore of Lake Nyasa, his porters became entangled in a monstrous web. Several giant spiders swiftly descended upon them, injecting the men with poisonous venom. Later, all the men's extremities swelled, they grew feverish, delirious and then died.
Simes claimed he drove the giant spiders off with his pistol.
Whether the Congo spider is real, or a myth remains to be seen. And hopefully, whomever the researcher is hunting for it will see the spider before it sees him.
 "Mysterious Creatures – A Guide to Cryptozoology," George M. Eberhart, Giant spider, p. 204.
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 "The Weiser Field Guide to Cryptozoology"
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