苏铁Cycas revoluta

苏铁Cycas revoluta

苏铁Cycas revoluta

苏铁Cycas revoluta

苏铁Cycas revoluta

苏铁Cycas revoluta

中文名(Chinese Name):苏铁
学名(Scientific Name):Cycas revoluta Thunb.
英文名(English Common Name):sago palm
别名(Chinese Common Name):辟火蕉、铁树、凤尾蕉
异名(Synonym):
科属(Family & Genus):苏铁科(Cycadaceae)苏铁属
形态特征(Description):树干高约2米,稀达8米或更高,圆柱形如有明显螺旋状排列的菱形叶柄残痕。羽状叶从茎的顶部生出,下层的向下弯,上层的斜上伸展,整个羽状叶的轮廓呈倒卵状狭披针形,长75-200厘米,叶轴横切面四方状圆形,柄略成四角形,两侧有齿状刺,水平或略斜上伸展,刺长2-3毫米;羽状裂片达100对以上,条形,厚革质,坚硬,长9-18厘米,宽4-6毫米,向上斜展微成“V"字形,边缘显著地向下反卷,上部微渐窄,先端有刺状尖头,基部窄,两侧不对称,下侧下延生长,上面深绿色有光泽,中央微凹,凹槽内有稍隆起的中脉,下面浅绿色,中脉显著隆起,两侧有疏柔毛或无毛. 雄球花圆柱形,长30-70厘米,径8-15厘米,有短梗,小孢子飞叶窄楔形,长3.5-6厘米,顶端宽平,其两角近圆形,宽1.7-2.5厘米,有急尖头,尖头长约5毫米,直立,下部渐窄,上面近于龙骨状,下面中肋及顶端密生黄褐色或灰黄色长绒毛,’花药通常 3个聚生;大孢子叶长14-22厘米,密生淡黄色或淡灰黄色绒毛,上部的顶片卵形至长卵形,边缘羽状分裂,裂片12-18对,条状钻形,长2.5-6厘米,先端有刺状尖头,胚珠2-6枚,生于大孢子叶柄的两侧,有绒毛。种子红褐色或桔红色,倒卵圆形或卵圆形,稍扁,长2-4厘米,径1.5-3厘米,密生灰黄色短绒毛,后渐脱落,中种皮木质,两侧有两条棱脊,上端无棱脊或棱脊不显著,顶端有尖头。花期6-7月,种子10月成熟。
分布(Distribution):产于福建、台湾、广东,各地常有栽培。日本南部、菲律宾和印度尼西亚也有分布。
用途(Use):苏铁为优美的观赏树种,多栽植于庭园或盆栽培。种子有毒,忌食用。
引自中国植物志英文版FOC Vol. 4
Cycas revoluta Thunberg, Verh. Holl. Maatsch. Weetensch. Haarlem. 20(2): 424, 426-427. 1782.
苏铁 su tie| Cycadaceae  | Cycas
Trunk to 3(-8) m × 45(-95) cm, base and sometimes distal part with numerous adventitious lateral branches or bulbils, apex tomentose; bark gray-black, scaly. Leaves 40-100 or more, 1-pinnate, 0.7-1.4(-1.8) m × 20-25(-28) cm; petiole subtetragonal in cross section, 10-20 cm, with 6-18 spines along each side; leaf blade oblong- or elliptic-lanceolate, strongly "V"-shaped in cross section, recurved, brown tomentose when young; leaflets in 60-150 pairs, horizontally inserted at ca. 45° above rachis, not glaucous when mature, straight to subfalcate, 10-20 cm × 4-7 mm, leathery, sparsely pubescent abaxially, base decurrent, margin strongly recurved, apex acuminate, pungent. Cataphylls triangular, 4-5 × 1.5-2.3 cm, densely brown tomentose, apex acuminate. Pollen cones pale yellow, ovoid-cylindric, 30-60 × 8-15 cm; microsporophylls narrowly cuneate, 3.5-6 × 1.7-2.5 cm, apex rounded-truncate, cuspidate. Megasporophylls yellow to pale brown, 14-22 cm, densely tomentose; stalk 7-12 cm; sterile blade ovate to narrowly so, 6-11 × 4-7 cm, deeply laciniate, with 21-35 lobes 1-3 cm; ovules 2 or 3 on each side of stalk, densely pale brown tomentose. Seeds 2(-5), orange to red, obovoid or ellipsoid, somewhat compressed, (3-)4-5 × 2.5-3.5 cm, sparsely hairy; sclerotesta not grooved on sides. Pollination May-Jul, seed maturity Sep-Oct.
Thickets on hillsides on islands, sparse forests on mainland; 100-500 m. Fujian (Lianjiang Xian, Ningde Xian, and some islands) [S Japan (Kyushu, Ryukyu Islands)]
A vulnerable, if not endangered, species in China. Its formerly wide distribution in E Fujian has now been severely reduced as a result of over collection by commercial dealers and habitat destruction. It was sporadically distributed in Fujian in the 1960s, but it is now uncertain that any wild populations still exist. Cycas revoluta is the most commonly cultivated cycad because of its ornamental appearance, hardiness, and adaptability.
(责任编辑:徐晔春)

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