Chloroplast data reveal two conflicting hypotheses for the positions of Campylostelium and Grimmia pitardii (Bryophyta)

Abstract

Due to conflicting morphological characters, the systematic placement of the Mediterranean-Central Asian Grimmia pitardii, lately considered a member of Campylostelium (Ptychomitriaceae), has been controversial. Phylogenetic inferences based on the chloroplast gene rps4 and the trnL-F region were performed to clarify its systematic affinities. Grimmia pitardii is consistently resolved as a member of a maximally supported clade together with the genus Campylostelium. This combined clade forms the sister group to a similarly high supported clade comprising Grimmia, Racomitrium, Coscinodon, and Schistidium. Consequently, G. pitardii must be treated as Campylostelium pitardii (Corb.) E. Maier. Analysis of the systematic position of Campylostelium and Ptychomitrium, traditionally placed in the family Ptychomitriaceae, yielded two conflicting topologies: one groups Ptychomitrium and Campylostelium, whilst the second branches Campylostelium first, grouping Ptychomitrium with Grimmiaceae.