Bryum gemmilucens R.Wilczek & Demaret, 1976

Osman, Imen Ben, Hugonnot, Vincent, Muller, Serge D. & Daoud-Bouattour, Amina, 2022, New bryophytes for Tunisia (North Africa). Part 2: other families, Cryptogamie, Bryologie 20 (11), pp. 173-185 : 177

Bryum gemmilucens R.Wilczek & Demaret

SPECIMENS EXAMINED. — Tunisia. Kroumiria, Jendouba Governorate, Delegation of Aïn Draham: Majen Ma, sterile, 36°46’52”N, 08°47’24”E, 505 m a.s.l. (site 2019-6), 02.IV.2019, Ben Osman & Hugonnot (TUN[TUN2019-221, TUN2019-226]); Majen Sghaïer, sterile, 36°46’53.44”N, 08°47’12.32”E, 506 m a.s.l. (site 2019-10), 02.IV.2019, Ben Osman & Hugonnot (TUN[TUN2019-210]).

REMARKS

Bryum gemmilucens was collected in a cork oak forest, on a wet lawn with Isoetes histrix Bory , Ophioglossum lusitanicum L. and Radiola linoides Roth (Majen el Ma) , and on a peat meadow, bordering temporary ponds (Majen Sghaïer).This tiny species was previously neglected in Tunisia, probably because it is inconspicuous or has only recently received taxonomic recognition ( Wilczek & Demaret 1976).

North African Mediterranean wetlands – semi-permanent lakes, peatlands and temporary pools – are habitats with high conservation value (Belouahem-Abed et al. 2011; Bouldjedri et al. 2011; Daoud-Bouattour et al. 2011; Rhazi et al. 2012). These fragile ecosystems are subject to strong pressures from overgrazing (Bouahim et al. 2010; Ferchichi-Ben Jamaa et al. 2014), which can cause severe trampling of the substrate. Paradoxically in Tunisia, wandering animals that scuff the superficial layer of soil can promote the spread of pioneer species such as Bryum gemmilucens , which are typically linked to open ground and bare soil (Demaret 1993). The occurrence of numerous long-lived gemmae buried in the substrate ( Wilczek & Demaret 1976) may contribute to this species’ success in such habitats.

Bryum gemmilucens is distinguished from similar species of the B. dichotomum complex by the occurrence of many very shiny yellowish-brown axillary gemmae with reduced apical appendages (Demaret 1993).

Bryum gemmilucens is primarily a European-western North American sub-oceanic temperate species, slightly penetrating to western Asia Minor and North Africa. It is scattered in Europe, including Macaronesia ( Hodgetts & Lockhart 2020), present in Northwestern Africa( Ros et al. 2013), Southwestern Asia ( Turkey; Kürschner & Frey 2020), and Northwestern America (California; Spence 1988).