[1] Goethe Univ Frankfurt, Inst Ecol Evolut & Div, D-60323 Frankfurt, Germany
[2] Biodivers & Climate Res Ctr BiK F, D-60325 Frankfurt, Germany
[3] Natl Bot Garden Belgium, B-1860 Meise, Belgium
[4] Res Inst Senckenberg, Dept Bot & Mol Evolut, D-60325 Frankfurt, Germany
[5] Polytech Univ Bobo Dioulasso, Dept Water & Forest, Bobo Dioulasso 01, Burkina Faso
[6] Univ Abobo Adjame, Stn Ecol Trop LAMTO, Abidjan, Cote Ivoire
[7] Aarhus Univ, Dept Terr Ecol, NERI Natl Environm Res Inst, DK-8600 Silkeborg, Denmark
[8] Univ Abdou Moumouni Niamey, Lab Garba Mounkaila Biol, Fac Sci, Niamey, Niger
[9] Univ Cheikh Anta Diop Dakar, Inst Environm Sci, Fac Sci & Technol, Dakar, Senegal
[10] Univ Abomey Calavi, Lab Appl Ecol, Cotonou 1974, Benin
[11] Univ Ouagadougou, Lab Plant Biol & Ecol, UFR Life & Earth Sci, Ouagadougou 03, Burkina Faso