Dipteris conjugata is a species of fern (in the family Dipteridaceae). It has a rhizome, and 2-3 tall stems with mid green or dark green fronds, which have several divisions to toothed lobes. It is grows in clearings, mountain ridges and in forest margins, from tropical and temperate Asia, northern Queensland in Australia and some islands in the Pacific Ocean. It has limited native medicinal uses.
It has a creeping rhizome,[3] covered with black shiny hairs,[4][5] or reddish brown hairlike scales.[1] The hairs are 4 to 5 mm long and 0.2 mm in diam.[2] The hairs are more like bristles on the older sections of the rhizomes.[5] It is up to 1 cm or more in diameter.[6]
It has Stipes (or stalks) that are normally between 0.4–2.0 m (1 ft 4 in – 6 ft 7 in) tall,[3][5] but stipes up to 2.5 m (8 ft 2 in) have also been found.[7] They have hair-like scales at base, which then becomes smooth and glabrous.[1][6] They are stramineous (straw coloured) to brown.[2]
The leaf stems appear at regular intervals along the rhizome.[5] and branch three or four times,[4] (these rhizomes are usually terrestrial, but can also climb trees). The fronds, or laminae ( are composed of two enormous leaflets, each up to 1 metre wide and broad>[8][9][10]
The mid green,[3] or dark green fronds,[1] but paler or glaucous underneath.[2] are between 0.5–0.7 m (1 ft 8 in – 2 ft 4 in) long and 0.5–0.7 m (1 ft 8 in – 2 ft 4 in) wide.[1][5][3] They are divided to the base into two spreading fan-shaped halves, which are further divided more than halfway into 4 or more unequal lobes, these lobes are again less deeply lobed once or more times. The ultimate lobes taper to a narrow apex with the edges deeply or coarsely toothed. The main veins are dichotomously branched several times.[6][1] The veins on the fronds are also dichotomously-branched with 2–4 main veins entering each of the lobes.[5][2] The juvenile fronds are tomentose (with a layer of downy hairs).[3]
On the lower surface of the fronds, are numerous,[10] small sori (spore producers),[4][9][5] they are irregularly scattered and of irregular size and shape.[6][3] They do not have indusia (umbrella-like covers) and have paraphyses (filament-like support structures) which are club-shaped.[1][2]
The leaves contain 2 ent-kauranoid hydroxy acids.[11]
In Fijian, it is known as koukoutangane,[4][3] or 'aivuiniveli'.[12] In Thailand it is called bua chaek[13] and bua cek in Singapore,[14]
It is written as 双扇蕨[1] or 破傘蕨,[3] in Chinese script, and known as shuang shan jue in Pinyin in China.[1]
The Latin specific epithet conjugata refers to the leaf having one pair of leaflets.[15][16]
It was described by Caspar Georg Carl Reinwardt in Syll. Pl. Nov. 2: 3 in 1828.[1][17]
Dipteris conjugata was also published by Tardieu & C.Chr., Fl. Indo-Chine 7(2): 442. 1941; Holttum, Rev. Fl. Malaya ed. 1, 2: 135, f. 55. 1955 [‘1954’]; Tagawa & K.Iwats., SouthE. Asian Stud. 5: 46. 1967; Acta Phytbtax. Geobot. 23: 52. 1968; Tagawa & K.Iwats., Fl. Thailand 3: 481, f. 49.1 & 49.2. 1989; Boonkerd & Pollawatn and Pterid. Thailand: 32, 78. 2000.[2]
It is native to tropical and temperate Asia, Australia and some islands in the Pacific Ocean.[13]
It can be found in temperate Asia, within the Ryukyu Islands of Japan. In tropical Asia, within Papua New Guinea, Cambodia (mainly Kampot[2]), Singapore,[5][18] Thailand, Vietnam,[13] and Hainan (in China), Taiwan, India, Indonesia, Malaysia (including on the slopes of Mount Ophir,[19]) and in the Philippines.[3][6][1] Also within Queensland in Australia,[20] and on the islands of New Caledonia,[13][6][3] (of New Zealand) and Fiji.[9]
Within Thailand, it is found in the provinces of Surat Thani, Phangnga, Nakhon Si Thammarat, Trang and Yala.[2] Within Singapore, it is found in the district of Kranji, Tanjung Gul and on the island of Pulau Tekong.[21]
D. conjugata grows on clay slopes,[2] in clearings,[14] ridges and on forest margins.[1][6] In East Kalimantan, Indonesia, it grows along rivers together with Nypa Palms.[6] In Borneo, it is found commonly growing with Histiopteris incisa (Thunb.) J. Sm. and Lygodium circinnatum (Burm.) Sw., along forest margins and paths.[22] In New Caledonia, it is found on sunny roadside banks.[9] The fern is also common in forest margins in high rainfall areas.[4]
The species occurs mainly at altitudes of 500 to 1,200 m (1,600 to 3,900 ft) above sea level in China,[1] 300 to 1,700 m (980 to 5,580 ft) in Malaysia,[5] and 300 to 2,900 m (980 to 9,510 ft) in Singapore.[6] In Singapore, it occurs on coastal cliffs,[14][3] and at the risk of landslides.[5][6] It is also
Dipteris conjugata is listed as Critically Endangered,[14] in the 2008 Singapore Red Data Book.[5][6][21] In Labrador Nature Reserve in Singapore, a large historic fern population was decimated,[21] when the reserve was downgraded to a nature park to only a few plants left in 2001.[6][3] It has also been found in Tanjong Berlayar Park in Singapore.[18][23]
To help conserve this fern, staff from the National Biodiversity Centre regularly check on the growth of the Dipteris in the Western Water Catchment. Using parangs and secateurs, they prune and clear the plants that may damage the fern, such as the invasive weed, Simpuh Air (Dillenia suffruticosa), the Weeping Fig (Ficus benjamina), and the Resam (fern) (Dicranopteris linearis).[21]
Elsewhere in other areas, at has been assessed as Least Concern (LC), as this species is widespread and not under any known threat.[2]
It is sometimes planted as an ornamental plant in Singapore.[14]
It can grown in poor to well drained soils and is mostly disease and pest resistant.[3]
Also specimens of the plant can be found in Cibodas Botanical Garden in West Java of Indonesia,[24] and in the Fernarium of Univerisiti Kebangsaan in Malaysia[25]
It has been used as a medicinal plant to treat various ailments,[26] such as in southern Thailand, the roots have been collected for used in traditional medicine.[6][14][3] In Fiji, it is used to treat male reproductive ailments.[3]
It also has another use, in the highlands of Mindanao in the Philippines, the large fronds are used as an umbrella.[6]
Dipteris conjugata is a species of fern (in the family Dipteridaceae). It has a rhizome, and 2-3 tall stems with mid green or dark green fronds, which have several divisions to toothed lobes. It is grows in clearings, mountain ridges and in forest margins, from tropical and temperate Asia, northern Queensland in Australia and some islands in the Pacific Ocean. It has limited native medicinal uses.
Dipteris conjugata là một loài dương xỉ trong họ Dipteridaceae. Loài này được Reinw. mô tả khoa học đầu tiên năm 1828.[1]
Dipteris conjugata là một loài dương xỉ trong họ Dipteridaceae. Loài này được Reinw. mô tả khoa học đầu tiên năm 1828.
双扇蕨(学名:Dipteris conjugata)为双扇蕨科双扇蕨属下的一个种,為中大型蕨類。又稱鐵雨傘、破傘蕨、半把繖、松葉蘭、雄過山、灰背雙扇蕨,是台灣唯一的雙扇蕨科植物
*根莖部
成體的莖直徑約1cm寬,根經常橫走狀,基部具窄批針型鱗片
* 葉部
葉柄長30-60cm,稻桿色,葉輪廓為圓形,裂成兩半,分別呈扇型,直徑20-60cm。為多回二叉撕裂之複葉,如同一把破傘。每一片裂片都有兩個主要葉脈(葉脈重複二叉分支),分裂至距離基部超過3/4處。末裂片寬1-2cm,頂端漸尖。葉主脈重複二叉分支,明顯凸起於葉背。葉緣增厚,具粗鋸齒缺刻。幼葉密布柔軟紅褐色易脫落絨毛;成葉光滑無毛,葉背綠灰色。
*孢子
孢子囊群小,紅棕色,沒有孢膜。散生狀,每一網眼中有一枚,著生在游離小脈上。
喜霧氣較重的空曠地,主要生長在向陽的岩壁上或道路邊坡,地生或岩生。常大片生長,呈成林狀態
印尼、菲律賓、太平洋群島、中國西南部等地,澳洲也曾發現
在台灣的分布為北端及南端,且在低海拔地區山脊線上。多生於岩壁。北部分布較南部為多,蘭嶼亦有分布。
觀賞價值高,亦為藥用植物
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中的日期值 (帮助)
ヤブレガサウラボシは、熱帯系の特異な形のシダ植物の一つ。左右対称に広がる葉の形は独特である。
ヤブレガサウラボシ Dipteris conjugata Reinw. は、ヤブレガサウラボシ科ヤブレガサウラボシ属の常緑性多年草で、この類では唯一の日本産の種である。
根茎は太くて径1cmほどにもなり、褐色で鱗片を密生し 長く横に這う。根茎の背面からはやや間を空けて葉を出す。葉には長い葉柄があり、時に2mに達する。葉柄は成熟すると藁色から濃い褐色で無毛となり、表面に強いつやがあって硬くなる。
葉身の形はとても独特である。まず葉柄の延長方向に伸びるような主脈はない。葉身はほぼ左右に大きく区分され、先端方向でほぼ完全に分断される。左右に伸びる裂片では葉脈は2-3回ほど二叉分枝しており、葉身もそれにあわせて、先端にゆくにつれ掌状に裂ける。裂けた部分はそれぞれに先がとがり、縁にはあらい鋸歯を持つ。なお太い葉脈からはずっと細い細脈がほぼ直角に出て、それらは複雑な網状になっている。
このような左右対称な葉は葉柄先端で折れ曲がって左右に大きく広がり、それぞれの裂片は扇形で先端は次第にしだれる。左右の裂片はそれぞれ長さ50cmに達することもある。葉は硬い髪質で厚くはないがばりばりと硬い手触りである。表側は黄緑から緑で強いつやがあり、遠くからも照りが見える。裏面は粉を吹いたような灰緑色を呈する。また、表面では葉脈はやや窪み、裏面では強く突出し、脈上には褐色の毛が生える。
胞子嚢群は丸く小さく、あるいは脈に沿って少し長くなるが包膜はない。側脈に沿って生じ、葉身の基部近く、太い脈付近から形成され、よく発達したものはほぼ裏面全体に出る。
なお、小さい苗では葉は左右相称でやや横長ながら裂け目のない単葉として広がり、成長するにつれてまずは先端中央から切れ込んで左右に分かれ(この時点ではハート形)、次に両列片にも側面から切れ込んで、次第に大きく細かく裂けるようになる。
この種の和名は破れ傘裏星で、葉の形が傘が破れた状態に似ていることからの名称であるが、むしろキク科植物のヤブレガサに見立てたものと思われる。裏星はシダを指す。ちなみに学名の属名は「二つの翼」を意味する。
山間部にはえ、森林内に見られることもあるが、森林の切れ目や林縁など、日当たりがよいところによく群生する。山腹から渓流周辺まで見られ、やや乾燥したところ、やせた赤土の場所、あるいは岩の上に出ることもある。このような生育条件はコシダのそれとも似ており、時にごく近くに生育しているのが見られる。これらは密生した群落を作る様子でも似ている。
西表島では観光地としても知られる浦内川の岸辺にもよく見られるし、カンピレーの滝周辺にも岩盤上などに小さな群落がいくつも見られる。
日本では琉球列島、八重山諸島の石垣島と西表島のみに分布する。国外ではインド、中国南部、タイ、マレーシアから南はニューカレドニアにわたる。ちなみにタイプ産地はインドネシアのジャワ島。中国名は灰背双扇蕨、あるいは単に双扇蕨という。
ヤブレガサウラボシ科はこの属一つからなる単型群であるが、化石は中生代から複数属が出ており、古い群のようである。ヤブレガサウラボシ属には世界に7種ほどが知られるが、日本にはこの種だけが分布する。中国には同属の D. chinensis Christ があるが、こちらはより小柄で、葉の裏面が灰色を帯びないという。なお、分類上はこの科をウラボシ科に収める場合もあり、その扱いには議論がある。
実用的な利害はない。
極めて独特の姿と、熱帯系の特異なシダであることから山野草部門からは関心が持たれるが、あまりに大きくなることから扱いづらい。それ以上に栽培が難しいことでも知られる。この点でもウラジロやコシダに似ている。
ヤブレガサウラボシは、熱帯系の特異な形のシダ植物の一つ。左右対称に広がる葉の形は独特である。