[Plant morphology] :perennial climbing vine-like big. Up to 10 meters or more. Root cylindrical, gray-brown skin, xylem yellow. Stem stout, old stems grayish brown, with irregular vertical stripes and horizontal cracks, twigs gray-green, with thin vertical stripes. Leaves alternate, leathery; leaf blade oval, elliptical, narrowly ovate or ovate-elliptic, apex obtuse or slightly acuminate, base rounded or nearly truncate, entire, green above, shiny, pale below green, glabrous, primary veins 3, ar