Colo Colo (mythology)

The Colo Colo or Colocolo is an evil rat-like creature from Mapuche mythology.
The colocolo is reputed to nest near a residence and sneak in, drinking blood from a sleeping resident, or sucking or extracting saliva, or licking utensil, causing debilitating weakness or tuberculosis. It must be exterminated in timely manner to save the life of the human.
It is often said to hatch from a stunted-looking "rooster's egg", and the young resembles a snake or burrowing lizard, but it later metamorphosing into a feathered rat form.
A type of wildcat is also called "colocolo", and this may perhaps be related to the origin of the lore.
According to Mapuche legend, the Colo Colo is a bloodthirsty animal which begins its life first as a hen's egg (or a rooster's egg by popular belief), and then as a snake or lizard that hatches out when the baking sun's heat is sufficient during incubation. Then after some while, it metamorphoses into this creature, like a feathered rat. The suspicious egg would be stunted or be small to come from a hen, so both the indigenous people and locals believe it must have been laid by a rooster.
The Colocolo dwells in caves near people's houses, and invading the home (alternative myth: it hides in a house as a newborn hatchling), feeds on the saliva of the residents, also licking their used utensils. Due to this the family will contract pulmonary tuberculosis and eventually die. Some sort of sympathetic magic is said to be at work. Whenever a suspected rooster egg is found, the people are wont to destroy it by burning.
The Colo Colo can be detected if someone of the house is feeling tired for no reason, or because of its cry, which is similar to an infant wailing. When it is suspected that a Colo Colo is in the house, a Machi must be contacted to exorcise the premises. Sometimes the only remedy is burning the building in order to kill the Colo Colo.
Julio Vicuña Cifuentes [es] published the data on the colo colo lore in urbanized area within the general area from Valparaíso to Concepción (northern coast to central Chile), including the vicinity of the capital city of Santiago.
At the northerly end, Colocolo was said to suck blood from people while they were asleep. (lore "a)" from La Serena)
At the capital or in the Santiago Metropolitan Region, Colocolo nests near someone's residence, and drinks the saliva (repeatedly from the same) person, who would suffer worsening weakness and disfigurement unto death, unless this was interrupted by eradicating the pest (lore "b)" of Santiago. Talagante), Colocolo, a black bird the size of a chercán (Northern house wren) whose saliva-drinking wasimmediately fatal (lore "c)" of Malloco [es]).
At locales nearer Concepción (451 kilometres (280 mi) south of the capital) but more inland, the Colocolo was a small bird similar to a bat, that entered rooms at night and brought saliva-sucking death (lore "d)" of Quella in Cauquenes). Or a little mouse whose saliva-drinking or leftover-eating would make person fatally ill. (lore "e)" of Coihueco de Chillán); Or an evil animal though unseen, and its crying call sounds like "colo-colo". Its drinking a person's saliva, caused death by fever, probably tuberculosis (lore "f)" of Coelemu).
This last version "f)" is the most common in the Valparaíso–Concepción parts of Chile.
In the more southerly Llanquihue and Valdivia Provinces, there extends similar lore about the colocolo as a subterranean lizard hatched from an underdeveloped egg (called rooster's egg), which kill humans by extracting their saliva.
Rodolfo Lenz [es]'s dictionary (1904) lists it as a mountain cat, i.e. Felis colocolo, commonly called "colocolo". According to Agustín Edwards Mac-Clure, colocolo used to signify an extinct or vanishing species of "catamountain" (wildcat), which folklore transformed into a lizard that burrows underground. "Coloco" is listed as a common name for the Pampas cat, which naturally hybridizes with other species.
The marsupial monito del monte is also called by the common name "colocolo", but the monotypic Dromiciops may just have been named from the onomatopoeia of its crying call, otherwise described as sounding like tzchí, tzchii, or kod-kod.