Fissidens Subgenus Aloma (Bryophyta) in Tropical Africa I. the Large-Celled Costate and Ecostate Species

A revision of the large-celled costate and ecostate species of Fissidens subgenus Aloma Kindb. from tropical Africa is presented. Fissidens flaccidus var. mammillosus Brugg.-Nann. var. nov. is described and the Neotropical F. mollis Mitt. is reinstated. Most African specimens previously identified as F. enervis Sim are referred to Fissidens dealbatus Hook. f. & Wilson, a new indigene for Africa. Fissidens molliculus P. de la Varde, F. hedbergii P. de la Varde and F. hookerioides Bizot & Onr. in Bizot are subsumed under F. dealbatus. Fissidens enervis s.str. appeared to be a rare species. The distributions in O’Shea (2006) are revised, updated and, when necessary, amended. Fissidens flaccidus Mitt. is for the first time reported from South Africa and Guinea, F. zollingeri Mont. from Ghana, F. grandifolius Broth. & P. de la Varde from Cameroon and F. usambaricus Broth. from Malawi and Gabon. Pending further research, F. palmatus Hedw. is excluded from the African bryoflora. It is stressed that, since vegetative and perichaetial stems are different, perichaetial stems (and leaves of perichaetial stems) are to be compared with perichaetial stems (and leaves of perichaetial stems), whereas vegetative stems (and leaves of vegetative stems) should be compared with other vegetative stems (and leaves of vegetative stems).