Lomaria discolor, synonym Blechnum discolor, commonly called crown fern (Māori: piupiu), is a species of fern in the family Blechnaceae. This species is endemic to New Zealand. As noted by C. Michael Hogan, this species is found in a number of forest communities in diverse locations within New Zealand, and is sometimes a dominant understorey component.

Spores are produced on specialised fronds. These are more erect, with a dark and shrivelled look.