中文名：石山苏铁
科名：Cycadaceae
属名：Cycas
描述：Trunk generally subterranean, often ellipsoid or abruptly tapered apically, sometimes to 60 × 20 cm above ground; bark white-gray, nearly smooth toward base of trunk. Leaves 25-40, 1-pinnate, 50-100 × 15-22 cm; petiole subterete, 10-20 cm, with 0-8 spines along each side of apical part; leaf blade oblong, flat; leaflets in 60-100 pairs, longitudinally inserted at ca. 90° to rachis, often overlapping, straight, 13-18 × 1.4-1.8 cm, thick, leathery, sparsely red-brown tomentose abaxially when young, later becoming dark green and glabrous, midvein nearly flat adaxially, raised abaxially, base usually truncate, decurrent, sometimes contracted, margin flat or only slightly revolute, apex mucronate, pungent at maturity. Cataphylls triangular, 3-4 × 1-1.3 cm, brown tomentose, apex soft. Pollen cones ovoid-fusiform, 20-30 × 6-8 cm; microsporophylls broadly cuneate, 1.5-3 × 1.2-1.5 cm, apical, sterile part subrhombic, thickened, densely pale brown tomentose, margin inconspicuously toothed, apex with short, upcurved mucro. Megasporophylls more than 30, tightly grouped, 8-14 cm, tawny tomentose when young, later glabresent; stalk 4.5-7.5 cm; sterile blade rhombic-ovate, 3.5-5.5 × 3-5 cm, margin pectinate, with 17-31 subulate lobes 1-2.5 cm, terminal lobe subulate, 3-4 cm; ovules 2 or 3 on each side of stalk, glabrous. Seeds 2-4, yellowish when fresh, brown when dry, obovoid or subglobose, 2-2.8 × 1.8-2.5 cm, apex mucronate; sclerotesta smooth. Pollination Mar-Apr, seed maturity Aug-Oct.
分布：广西
来源：Flora of China