First Appearance: Captain America Comics #2 (Apr. 1941): "The Devil and the Green Plague"
Number of Appearances: 1
Enemy of: Makkari
Worked for: Kro
It seems that Kepiquatzl was named after Quetzalcoatl, who was primarily a Mayan and Aztec god. Kepiquatzl's origins and the exact religious culture he was supposedly representing may be a little precise. Kepiquatzl's story takes place in Brazil, while Quetzalcoatl was worshiped most prominently in Mexico. But Quetzalcoatl came to Mexico-based Aztecs from previous Mayan and Toltec cultures, which ranged into Central America and parts of South America, including Guatemala and Brazil.
Suggested links for further research about this character and the character's religious affiliation: