The Fire Eater
The fire eater, Tuckerella flamma, is a little known member of the Acari subclass. Unlike its better knowns cousins, the ticks, the fire eater does not feed on living beings. Neither does it feed of off fire, but rather, it finds its nourishment in the ashes left behind after a fire.
Although little known by most pundits, the fire eater is an essential component of the development of many ecosystems. Mainly found in dry and hot climates, the fire eater fulfills a crucial step in the recolonization of fire-struck environments. By digesting the ashes, it filters out most of the toxic products of combustion, which it stores in special cells called toxocytes. This makes fire eaters extremely toxic, and protects them from predation. At the same time, it allows other animals and plants to colonize the ash-ridden ground after a forest fire that much faster. It is believed that most ecosystems that regularly experience forest fires would not be able to recuperate fast enough without the fire eater.
Until the appearance of Christianity, fire eaters have been considered largely beneficial animals. The old tribes believed that they actually ate the fire, and stopped it spreading too far. Thus, fire eaters were praised, and considered a good omen. However, after the appearance of the Christian religion, they were considered Satan's spawn, the only creature able to survive god's purifying flames. Whether or not they were appreciated by humans had little impact on the fire eater population.
In the latter half of the XXth century, it seemed as if a new strain of fire eaters was evolving. Indeed, there was much discussion regarding Tuckerella flamma urbanus, a new sub-species of fire eaters found manly in ashtrays.
The abundance of smoking in those days created the first urban habitat for fire eaters, and they spread rapidly through the world, adapting to their new environment with incredible speed. However, since smoking laws have become stricter in the last decade, the number of homes for this sub-species has diminished drastically. As populations became more isolated from each other, they soon started dwindling, and at the current speed, urbanus will be extinct in another twenty years.
Meanwhile, the original fire eater seems to have found a good standing with humans once more, and it has become increasingly common that posh people keep a population of the small animals in their fireplace.