Lowland deciduous thorn woodland & shrubland geocomplex. 1. Saxicolous vegetation: Zehntnerella squamulosa community. Gneiss rock outcrops 2. Deciduous succulent thorn-woodland: Pilosocereus pachycladus-Mimosa tenuiflora community, with Melocactus zehntneri, Senegalia bahiensis, Syagrus coronata, Cereus jamacaru, Pilosocereus gounelleii, etc. Hillsides with stony (quartz and gneiss) squeletic regosols. 3. Deciduous succulent thorn-woodland and shrubland: Espostoopsis dybowskii-Caesalpinia laxiflora community, with Pilosocereus pentaedrophorus, P. pachycladus, Leocereus bahiensis, Commiphora leptophloeos, Opuntia inamoena, etc. (in Juazeiro region). Extensive glacis and plains with sandy-loamy soils (arenic regosols and luvisols). 3’ Deciduous succulent thorn-woodland and shrubland: Pilosocereus catingicola-Caesalpinia pyramidalis community, with Syagrus coronata, Cnidoscolus phyllacanthus, Pseudobombax simplicifolium, etc. (in Senhor de Bonfim-Riacho Jacuípe region). Extensive glacis and plains with sandy-loamy soils (arenic regosols and luvisols). 4. Phreatophyllous thorn-woodland: Parkinsonia aculeata-Prosopis juliflora community. Clay-silty soils with shallow water table (gleyic luvisols). 5. Flooded palm-woodland: Geoffroea spinosa-Copernicia prunifera community with Acacia piauhyensis, Ruprechtia laxiflora, Zizyphus joazeiro. Seasonally flooded alluvial plains of São Francisco River (sodic humic vertisols and fluvisols). Graphic geobotanical interpretation based on our own field transect data in Bahia (1996) and cited references.