Didymodon heilongjiangensis (Pottiaceae, Musci), a new species from Heilongjiang Province, China and its phylogenetic position based on molecular data

Abstract

Didymodon heilongjiangensis is described as a new species from Nianzishan District, Heilongjiang Province, China. It is mainly characterized by triangular to ovate‐lanceolate leaves that are erect to erect‐patent when moist, acute leaf apices, leaf margins recurved to near leaf apex, yellowish color in KOH, percurrent to short‐excurrent costa that is widened toward apex, laminal cells with low papillae over the transverse walls, which reach the two adjacent cells, and marginal basal cells with thickened transverse walls. A phylogenetic analysis based on DNA sequences of ITS, rps4, trnM‐trnV confirms that D. heilongjiangensis belongs to the genus Didymodon s.str. The new species is fully illustrated and its affinities are discussed in detail.