In Spanish speaking countries without Italian influence (Argentina and Uruguay have it),
Luca is often interpreted as feminine name, because of the ending in -A.
This is a mistake, but a popular Spanish name book as
El libro de los nombres by
Josep Maria Albaigès list
Luca as feminine form of
Lucas. I don't know if Albaigès has found some documents of traditional use of
Luca as feminine form of
Lucas in Spanish, if he reflects the fact that nowadays it is considered the feminine form (originated by a mistake) or, simply, if it is an Albaigès's error (name books often have errors).
Lumia
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