Lejeunea pocsii R.M.Schust. is a heterotypic synonym of L. helmsiana (Steph.) Steph. (Lejeuneaceae, Marchantiophyta)
Renner, Matt A.M. Brown; Wardle, Glenda M.
Two names, Lejeunea helmsiana and L. pocsii, are currently applied to New Zealand Lejeunea that possess the following three characters: a multicellular first lobule tooth, an inflated lobule carinal region, and pentacarinate perianth. To explore whether the recognition of two species is warranted we searched for size and shape differences in underleaves and lobules among nine individuals with these three characters. Cluster analysis identified three groups on the basis of size data, and two on the basis of shape. There was no concordance between cluster membership and individual membership for modules, which is evidence against the existence of more than one taxon. Allometric data describe a relationship that appears to account for differences between types of L. helmsiana (Steph.) Steph. and L. pocsii R. M. Schust. Here we formally reject the hypothesis that the names L. helmsiana and L. pocsii apply to separate evolutionary entities, and accordingly synonymise L. pocsii with L. helmsiana.