There is a venerable Spanish de Losada noble line which originated in the Galicia region early in the Reconquista. Reference to them in the time of Olivares can be found here; and they can be found in many places in Spanish history including the founding of Caracas, Venezuela!
Accounts can be found of some legendary figures - such as Juan and Diego de Losada who are said to be the founders of the Losada lineage having been granted land near Quiroga in Galicia because they somehow dealt with a plague of large lizards with stone slabs, giving rise to a coats of arms with two or six lizards and a stone slab! An example of this genre follows: