This name is not recognized as a valid taxon; it is a plant trade fabricated name, and the taxon does not occur naturally, or in the wild.

"Alocasia × amazonica is a hybrid whose parents are unknown. ...In terms of botanical origin and proper nomenclature, it remains somewhat of a mystery. Some experts today consider Alocasia x amazonica to be a manufactured horticultural name rather than a legitimate scientific name. Although amazonica seems to suggest that this plant is native to the Amazon River in Brazil, none of the species of Alocasia are native to South America.

Some authorities currently believe that Alocasia × amazonica is simply a name applied by Salvadore Mauro in the 1950s to a hybrid created by him at his Miami, Florida nursery known as Amazon Nursery. Mauro never published or registered this hybrid name, however."
https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=259315&isprofile=0&