Hope this scary spore doesn't develop a taste for us.
As bad as any horror movie ever, from Boingboing, this description from Lawrence Weschler's Mr. Wilson's Cabinet Of Wonder: Pronged Ants, Horned Humans, Mice on Toast, and Other Marvels of Jurassic Technology.
Deep in the Cameroonian rain forests of west-central Africa there lives a floor-dwelling ant known as Megaloponera foetens, or more commonly, the stink ant. This large ant -— indeed, one of the very few capable of emitting a cry audible to the human ear -— survives by foraging for food among the fallen leaves and undergrowth of the extraordinarily rich rain-forest floor.There is even an utterly creepy video clip SHOWING the crazy ants including the giant spike growing out of the ant's head. UGH.
On occasion, while thus foraging, one of these ants will become infected by inhaling the microscopic spore of a fungus from the genus Tomentella, millions of which rain down upon the forest floor from somewhere in the canopy above. Upon being inhaled, the spore lodges itself inside the ant’s tiny brain and immediately begins to grow, quickly fomenting bizarre behavioral changes in its ant host. The creature appears troubled and confused, and presently, for the first time in its life, it leaves the forest floor and begins an arduous climb up the stalks of vines and ferns.
Driven on and on by the still-growing fungus, the ant finally achieves a seemingly prescribed height whereupon, utterly spent, it impales the plant with its mandibles and, thus affixed, waits to die. Ants that have met their doom in this fashion are quite a common sight in certain sections of the rain forest.
The fungus, for its part, lives on. It continues to consume the brain, moving on through the rest of the nervous system and, eventually, through all the soft tissue that remains of the ant. After approximately two weeks, a spikelike protrusion erupts from out of what had once been the ant’s head. Growing to a length of about an inch and a half, the spike features a bright orange tip, heavy-laden with spores, which now begin to rain down onto the forest floor for other unsuspecting ants to inhale.