El Cuero, the lake 'hide'
El Cuero ('the hide') is a creature of Mapuche and Chilean lake lore: a flat, octopus-like skin with claws on its edges that lies on the bottom of lakes and wraps around swimmers to drag them under.
1915 CE · -39.25, -72.20 · status: legend
The account
It is reported from the lakes of Araucanía and northern Patagonia on both sides of the Andes, and Mapuche tradition calls a similar being trülke wekufe. The year used here is approximate: it marks the period when Chilean folklorists such as Julio Vicuña Cifuentes collected the story in print. The pin marks the Araucanian lake district, not a single lake.
The sceptical view
Folklorists read the Cuero as a warning about cold, weed-choked lakes where swimmers drown; some cryptozoologists have suggested large freshwater rays or misidentified mats of vegetation.