The origins of these tales date back as far as the 8th century when the Arabs brought their ideas and concepts of national fairytales (Cuento) and folklore to Spain.
[1] The Arabian impacts on Spanish folklore would lead to Spain playing a mediator position between the European regions and the Muslim world and culture.
Not only would Spain play this crucial role in the Muslim world, but they would also incorporate Indian cultural aspects into their tales and oral traditions.
In Asturias and Cantabrian regions, they believe in what is known as the Culebre, which is a giant, winged serpent-dragon that is an inhabitant of caves and guards the treasures found inside them.
Each suitor that does not emerge from the riddle victorious, faces the fate of death, especially since Antiochus dictates the answers as incorrect even if they are a mildly acceptable response.
It is quite common in Spanish folklore for riddlers to be feminine over masculine because it creates a sexual tension between the female character who either poses the question, or answers it, and this confrontation of power.
This choice is specifically made in the tales to display to the inhabitants of Spain a female heroine, who stereotypically starts off as powerless, but finds strength and power in her wit/wisdom by posing or answering a riddle.