The "Bicha Pintada", located on the right bank of the Ribeira do Codes, below the belvedere of Penedo Furado(Portugal)
is a fossil that, according to some scholars, is believed to be more than 480 million years old, inserted in the top of a layer of quartzite Dark gray, 30 cm thick.
It is formed by a groove of variable thickness, with 5 cm of average width and 1 cm of depth, of rectangular outline and regular lateral limits, meandriform, sinuous, with about 8.1 m of visible extension. At the same time and on the same layer, unrecognizable vermiform galleries occur.
This type of structure is interpreted as having grooves produced by the activity of feeding and displacing trilobites in a sandy bottom.
Due essentially to its sinuous serpentine form, successive creations of legends, myths and stories of the popular knowledge were created.