The Riccietum jovet-astii- argenteolimbatae ass. nov. of the Jabal Arays area, Yemen- life strategies of a remarkable xerotropical African bryophyte community
Based on a phytosociological analysis, the terrestrial Riccietum jovet-astii- argenteolimbatae, grouped within the Mannion androgynae alliance (Barbuletalia/Barbuletea unguiculatae) is described from South Arabia (Jabal Arays area, Yemen). It is typical of shallow soils overlying the volcanic rock outcrops in the understory of monsoon-affected Sterculia africana subsp. arabica woodland. It consists of a great number of riccioid and marchantioid liverworts with strong xerotropical African relationships. Character species are R. atromarginata var. jovet-astii, and the palaeo-African R. cf. albolimbata and R. argenteolimbata. The latter two are new records for the Arabian Peninsula with remarkable range extensions. In addition to the syntaxonomic and ecological description of the community, a life strategy analysis has been carried out: shuttle species, characterized by large spoores clearly dominate, indicating short-range dispersal and the formation of a diaspore bank. Further more, the geophyte and colonists strategy occur, but both of minor importance.