TAXONOMIC REVISION OF THE MOSS FAMILY DIPHYSCIACEAE M. FLEISCH. (MUSCI)

Abstract

  The Diphysciaceae are a small family of mosses consisting of one genus, Diphyscium Mohr. The family is distinguished by the unique combination of short setae, immersed capsules, collared axillary hairs, distinctly differentiated perichaetial leaves, and arthrodontous peristomes with pleated endostomes and exostomes that are rudimentary or lacking. The Diphysciaceae are taxonomically revised based on field studies, examination of 2500 specimens from 36 herbaria, and an extensive review of relevant literature. Fifteen species and one subspecies are recognized in the family: Diphyscium chiapense D. H. Norris, D. chiapense D. H. Norris subsp. unipapillosum (Deguchi) T. Y. Chiang & S. H. Lin, D. domingense (Brid.) W. R. Buck & Steere, D. fasciculatum Mitt., D. fendleri Müll. Hal., D. foliosum (Hedw.) Mohr, D. fulvifolium Mitt., D. kashmirense (H. Rob.) Magombo, D. longifolium Griff., D. lorifolium (Cardot) Magombo, D. mucronifolium Mitt., D. perminutum Takaki, D. pilmaiquen (Crosby) Magombo, D. pocsii (Bizot) R. H. Zander, D. satoi Tuzibe, and D. suzukii Z. Iwats. The following taxa are newly synonmized: Diphyscium foliosum F. Weber & D. Mohr var elatum Thér. = D. foliosum (Hedw.) Mohr, Diphyscium peruvianum Spruce ex Mitt.= Diphyscium longifolium Griff., and Diphyscium cumberlandianum Harvill = Diphyscium mucronifolium Mitt. Lectotypes for D. foliosum, D. domingense, and D. longifolium are newly selected. It is hypothesized here that D. chiapense is a polyploid, presumably through autopolyploidy.