There are two subspecies of the purple finch, H. p. purpureus and H. p. californicus. H. p. californicus was identified by Spencer F. Baird in 1858. It differs from the nominate subspecies in that it has a longer tail and shorter wings. The plumage of both males and females is darker, and the coloration of the females is more greenish. The bill of C. p. californicus is also longer than that of the nominate subspecies.
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