Pteridophytes are a large family of plants, including Adiantaceae, Cyatheaceae, Dryopteridaceae, Polypodiaceae and so on.
Adiantaceae.
Endangered species under national second-class protection. Small and medium-sized herbaceous ferns that have been growing on land for many years have great body variation. 5-20cm high. Rhizomes are short, erect or slender, with tubular stele, covered with brown or black, thick and usually entire lanceolate scales. A shape of leaves, spirally clustered, scattered or gathered in two rows, not attached to the rhizome through joints; Petiole black or reddish brown, shiny, usually thin and round, as hard as iron wire, with one or two vascular bundles at the base, one upward; Most of the leaves are pinnate compound leaves or bifurcations over 1-3 weeks, a few are fan-shaped single leaves, grassy or thick paper, a few are leathery or membranous, and many are smooth and hairless; Leaf axis, feather axis and kohane axis are all the same color and shape as petiole; The terminal pinnae has different shapes, such as oval, fan-shaped, group fan-shaped or split-shaped, with serrated edges, a few split or whole edges, sometimes connected with the petiole by joints, and often falls off after drying. Veins are separated, rarely reticulate, and there are many branches radially from the base upward or from the base to the periphery, with the top branch reaching the edge and visible on both sides. The leaf margin is serrated, and the veins of the leaf margin or the top margin of the feather of the long spore leaf are reversely rolled into false veins. There are many shapes of false crowns, such as round, kidney, half moon, rectangle and ellipse. The upper edge of the false crown (the edge connected with the feather after turning over) is deep, shallow or truncated. Sporangia is spherical, long-stalked, and the girdle is erect, and it is mostly composed of 18 thickened cells (sometimes up to 28); Spores are quadrangular, light yellow, transparent and smooth, and have no peripheral walls. Born in thin soil, cracks or grass on the surface of warm, humid and shady rocks at an altitude of about 205 cm. This variety is the most primitive type of Adiantum.
(1) Cyatheaceae: tree fern, tree height 1-6m, trunk height 1-3m, DBH 10-20cm. The leaves are pinnate for three times, and are 1-3m long. They are born at the top of the stem and the young leaves are curly. Mainly distributed in the southeast and southwest, it is born in gullies at an altitude of 400-900m and wet slopes at the sunny side of streams, and sometimes scattered in shrubs at the edge of forests. Southeast Asia and southern Japan are also distributed. Mesozoic was widely distributed on the earth, but now the distribution area is shrinking. Protection of endangered species at the national level.
(2) Dryopteridaceae: Ardisia Emei, a perennial herbaceous fern with a height of 25-35cm. Rhizomes are short with sparse scales and petioles. The pinnate leaves are divided into three or four periods, and the last period is only 1 veinlets. Distributed in Yunnan, Guizhou and Sichuan, it is born on wet rocks or trunk beside streams at an altitude of 800- 1500m.
(3) Dryopteridaceae: perennial epiphytic herbaceous ferns of Dryopteridaceae. Leaf type ⅱ, the basal leaves are attached to the trunk, and the leaves can be irregularly branched into antlers for 3-5 times. Rare plants newly discovered and distributed in China. Yingjiang, which is only distributed in the southwest of Yunnan, is born in the tropical rain forest at an altitude of 2 10-950m-950 m, and is mostly attached to trunks and branches. It is also distributed in Indian zhina Peninsula. Rare species under national second-class protection.