A taxonomic contribution on the European cleistocarpous species of Pottiaceae (Musci)

The morphological characters of the sporophyte and gametophyte of the genera Phascum L. ex Hedw., Microbryum Schimp., Acaulon Mull. Hal. and Aschisma Lindb., are delimited. Leptophascum J. Guerra &, M.J. Cane stat, nov. (type: Leptophascum leptophyllum (Mull. Hal.) J. Guerra & M.J. Cane comb. nov.), and Protobryum J. Guerra & M.J. Cane nom. nov, are proposed to replace Mildeella Limpr. hem. illeg., las a genus with intermediate characteristics between Phascum and Pottia (Rchb.) Furnr.). In addition, Phascum cuynetii Bizot & R.B. Pierrot ex J. Guerra et al. is transfered to the genus. Aschisma Lindb. (A. cuynetii J. Guerra & M.J. Cano comb, nov.).