Peter's Blog: Dipteris conjugata (雙扇蕨)

Dipteris conjugata is in the genus Dipteris and the family Dipteridaceae. There are only 2 genera of the family Dipteraceae in the world, Dipteris and Cheiropleuria, about 12 species in total. There are both genera in Taiwan with 1 species each and in addition to this species, the other is Cheiropleuria integrifolia. Ferns of Pteridaceae have existed on the earth before the Jurassic era, and have remained until now. They are listed as "relict plants" and are standard living fossils. There are two species in Taiwan, which can be said to be extremely precious.

Dipteris conjugata is native to Taiwan, S. W. China, Indonesia, the Philippines and Islands of Pacific. In Taiwan, it is distributed in low-altitude areas in the north and south and more in the north than in the south. It is a terrestrial or lithophyte fern, grows on sunny rock walls, ridgelines, or road slopes, especially rock walls, at the edge of forests. The shape of its blade is special. The circular outline first divided into two halves from the middle and then each is multiply binary splits. It makes the blade looks like two broken fans side by side, hence it has Chinese name "雙扇蕨", and some people regard it as a broken umbrella so it is also called "破傘蕨" (broken umbrella fern) in Chinese. The diameter of its blades can reach 60 cm, and the stipes can reach more than 60 cm so it can be regarded as a medium-to-large fern and because they have long creeping rhizomes so they often grow in groups in the wild.

Dipteris conjugata

（2014.8.1 Northern Taiwan）

About Dipteris conjugata

◆	Classification: Genus Dipteris, Family Dipteridaceae
◆	Scientific Name: Dipteris conjugata Reinw.
◆	Common Name: Broad-leaf Fern、Coupled Dipteris
◆	Chinese Name: 雙扇蕨、破傘蕨、鐵雨傘、半把繖、松葉蘭、雄過山、灰背雙扇蕨
◆	Origin: Taiwan, S. W. China, Indonesia, the Philippines, Islands of Pacific
◆	Growth environment: In Taiwan, it is distributed on sunny rock walls, ridgelines, or road slopes, especially rock walls, at the edge of forests in low-altitude areas in the north and south and more in the north than in the south
◆	Growth habit: Terrestrial or lithophyte
◆	Hight: Up to 1 meter or more
◆	Rhizome: Long creeping, about 1 cm in diameter, densely scaly, scale black, setose
◆	Frond
	》	Stipe: Stout, 40-120 cm, with hairlike scales at base
	》	Blade →Fan-shaped, up to 60 cm in diameter, cut into 2 halves, each half multiple binary splits, main loabes narrowly lanceolate, with 2 main veins →Thin coriaceous, margins coarse serrate
	》	Veins →Netted veins, areolae with included veinlets →main veins multiple two-forked, prominently protruding on abaxial side
◆	Sori
	》	orbicular, born on the included veinlets in areolaes
	》	No Indusia

Dipteris conjugata is native to Taiwan, S. W. China, Indonesia, the Philippines and Islands of Pacific. In Taiwan, it is distributed on sunny rock walls, ridgelines, or road slopes, especially rock walls, at the edge of forests in low-altitude areas in the north and south and more in the north than in the south.