A phylogenetic analysis of the boreal lichen Mycoblastus sanguinarius (Mycoblastaceae, lichenized Ascomycota) reveals cryptic clades correlated with fatty acid profiles

► The 'bloody heart lichen' Mycoblastus sanguinarius consists of two, widespread, cryptic species. ► Mycoblastus sanguinarioides, previously thought confined to Tasmania, is widely distributed. ► Low level clades within both of the cryptic species are correlated with fatty acid profiles. ► Early chemical differentiation may play a role in incipient speciation events.