Description
Summary:Racomitrium Brid., in its traditional circumscription is poorly represented in the moss flora of Madagascar and hitherto only one specimen of this genus has been discovered on this fourth largest island in the world. It was collected in 1924 by Perrier de la Bathie on the Tsaratanana Massif, and Thériot (1926) reported it as an unnamed form of Racomitrium lepervanchei Besch., a species endemic to Réunion Island. As Racomitrium proved to be heterogeneous, it was split into six segregates (Ochyra, Żarnowiec et al. 2003; Bednarek-Ochyra, Ochyra, Sawicki et al. 2014; Bednarek-Ochyra, Sawicki, Ochyra, et al. 2015; Sawicki et al. 2015), R. lepervanchei was placed in the genus Bucklandiella Roiv. Nevertheless, the voucher specimen was not studied by De Sloover (1977) in his survey of African Racomitrium and this material was assigned either to R. crispulum (Hook.f. & Wilson) Wilson (Crosby et al. 1983) or Bucklandiella membranacea (Mitt.) Bedn.-Ochyra & Ochyra (Marline et al. 2012), as R. lepervanchei was considered to be conspecific with these species (Clifford 1955; Lawton 1973). The specimen from the Tsaratanana Massif has distinct auricles and broad, flattened costa with 6–8 enlarged ventral guide cells, which are typical of Bucklandiella subsecunda. This is a pantropical oreophyte, widespread in tropical and subtropical Asia (Frisvoll 1988), subSaharan Africa (Bednarek-Ochyra and Ochyra 2012a, 2013; Ochyra and van Rooy 2013), Central and South America (Bednarek-Ochyra et al. 1999; Bednarek-Ochyra and Ochyra 2012b; Ellis, Bakalin et al. 2013) and the maritime Antarctic (Ochyra, Lewis Smith et al. 2008). Fil: Ellis, L. T. Natural History Museum; Reino Unido Fil: Afonina, O.M. Russian Academy Of Sciences. Komarov Botanical Institute; Rusia Fil: Czernyadjeva, I. V. Russian Academy Of Sciences. Komarov Botanical Institute; Rusia Fil: Konoreva, L. A. Russian Academy Of Sciences. Komarov Botanical Institute; Rusia Fil: Potemkin, A. D. Russian Academy Of Sciences. Komarov Botanical Institute; Rusia ...