Systematics of the Hypopterygium tamarisci complex (Hypopterygiaceae, Bryopsida): Implications of molecular and morphological data studies in australtemperate rain forest bryophytes

Five Hypopterygium species, H. tamarisci, H. laricinum, H. tenellum, H. mue lleri, and H. debile, exhibit remarkable morphological similarities and for m a species complex (H. tamarisci complex). This study unravels the problematic delimitation of the species in this com plex using molecular (cpDNA trnL(UAA) intron) and morphological data. Seque nces of the trnL(UAA),, intron of taxa belonging to the H. tamarisci comple x are remarkably similar. In a maximum parsimony tree, the taxa form a poly tomous clade within one well-supported clade of other hypopterygium species (H. filiculaeforme and H, didictyon). The Hypopterygium clade is well-sepa rated from both the outgroup species, Lopidium concinnum, and from the clad e of Canalohypopterygium tamariscinum and Catharomnion ciliatum. Morphologi cal research showed, that the "taxa" of the H, tamarisci complex can not be sharply delimited from one another, but they can be delimited from the oth er Hypopterygium species as a single, variable and widely distributed speci es: H. tamarisci. Hypopterygium debile, H. laricinum, H. muelleri, and H, t enellum are shown to be synonymous with H. tamarisci.