The disentanglement of Andreaea alpina Hedw. (Andreaeaceae): Typifications and nomenclatural changes

The name Andreaea alpina was validly published in Hedwig's 1801 work Species muscorum frondosorum, but the entity itself can be traced back in the pre-Linnaean literature to Dillenius of 1741 where it was described under "Lichenastrum". Three hebarium sheets in the Hedwig-Schwägrichen Herbarium in G are associated with A. alpina: one that was identified as A. rupestris (G00056451), one as A. obovata (G00056454), and one non-original specimen that was indicated as A. alpina (G00040015). The latter sheet had been annotated "holotype", and later "lectotype", for this name, although formal typification of the name has yet to be effected via publication. To clarify the confusion over the true identity of the material in G and thus over the correct application of the name Andreaea alpina, a lectotype is designated herein from the original material in the Hedwig Herbarium. The chosen material corresponds most closely to the validating description and represents material that was seen by Hedwig for his 1801 work. In consequence of this typification, the name Andreaea hookeri is proposed for the entity that had erroneously come to be known as Andreaea alpina.