A taxonomic synopsis of Acianthera (<em>Orchidaceae: Pleurothallidinae</em>) in Peru, including two new species

A taxonomic synopsis of Peruvian Acianthera including 35 accepted species is presented. An artificial key and maps for known localities from all these species are also included. Acianthera berlinensis sp. nov. and A. marleniae sp. nov. are described and illustrated as new species based on specimens collected in the Peruvian regions of Amazonas and Cajamarca, respectively. Information on the distribution and habitat is provided for both new taxa, followed by a discussion comparing the traits that distinguish them from their closest relatives. A. consatae, A. dodsonii, A. lamia, A. scalpricaulis and A. toachica, previously known only from Ecuador and Bolivia, are herein reported for the first time for the Peruvian flora