Wood, stem, and root anatomy of Basellaceae with relation to habit, systematics, and cambial variants

Wood data from wider stem, root, and root-stem transition of a mature plant of Anredera baselloides are analyzed for quantitative and qualitative feat ures. Distinctive characters of A. baselloides include presence of successi ve cambia in wider stem, root, and root-stem transition; other types of cam bial variants are newly reported for the family. Systematic distribution of successive cambia in Caryophyllales does not parallel cladistic schemes fo r the order, and possible reasons are advanced. Wood features other than su ccessive cambia are compatible with relationship to the other families of P ortulacinae (Cactaceae, Didiereaceae, Hectorellacaeae, Portulacaeae) except for features related to habit, particularly the scandent habit. These feat ures (mostly newly reported for Basellaceae) include restriction of vessels to central portions of fascicular areas (vessels thereby likely protected from torsion); some vessels wide but many narrow; all ray cells and ray-adj acent axial parenchyma with thin walls; (interxylary) phloem strands in ray -adjacent axial parenchyma (with cambia that augment the phloem strands); a nd intraxylary phloem. Tubers contain pith phloem strands adjacent to which cambia produce secondary xylem and phloem. Druses and mucilage cells in co rtex and rays and storying in axial xylem cells are newly reported for Base llaceae.