Figure 2.

Overview of informative Apocynaceae wood anatomical characters based on LM sections (A–L, N) and SEM surfaces (M, O). (A) Willughbeia coriacea—cross section, mainly solitary vessels (arrow). (B) Thevetia ahouai—cross section, vessels mainly in radial multiples (arrow). (C) Gongronemopsis tenacissima—cross section, vessels in radially oriented clusters including many narrow (arrows) and few wide vessels (vessel dimorphism). (D) Minaria acerosa—tangential section, ground tissue composed of densely pitted imperforate tracheary cells (tracheids, arrow pointing right), which are difficult to distinguish from narrow vessels with simple perforations (tilted arrow pointing left) surrounding wider vessels (tilted arrow pointing right). (E) Kanahia laniflora—tangential section, ground tissue composed of fiber‐tracheids with distinctly bordered pits (arrows). (F) Cerberiopsis candelabra—tangential section, ground tissue composed of few minutely bordered libriform fibers (arrows point to pits). (G) Dyera costulata—tangential section, uni‐ (arrow pointing left), and multiseriate rays (arrow pointing right). (H) Aspidosperma oblongum—cross section, apotracheal axial parenchyma (arrow). (I) Aspidosperma album—cross section, paratracheal axial parenchyma (arrow). (J) Secamonopsis madagascariensis—tangential section, laticifer in multiseriate ray (arrow pointing left) and vasicentric tracheids (arrow pointing right). (K) Leptadenia arborea—cross section, cambial variant (arrows) leading to zones of nonlignified xylem (in blue) including fibers, parenchyma, rays, and traces of interxylary phloem cells. (L) Mandevilla rugellosa—radial section, septate libriform fibers (arrows pointing to septa). (M) Pentopetia grevei—tangential surface, prismatic crystals in ray cells (arrow). (N) Aspidosperma megalocarpon—radial section, prismatic crystals in chambered axial parenchyma cells (arrow), (O) Funastrum clausum—cross section, druses in nonlignified tissue.