Alsophila albidosquamata, synonyms Cyathea albidosquamata and Sphaeropteris albidosquamata, is a species of tree fern native to the Maluku Islands, New Guinea and the Bismarck Archipelago, where it grows in rain forest and montane forest at an altitude of 620–2,500 metres (2,000–8,200 ft). The trunk is erect and about 2 m tall. Fronds are bi- or tripinnate and 1–1.5 m in length. The lower surface of the rachis is covered in scales and the stipe has scattered scales throughout its length. These are glossy and pale, with dull, fragile edges. Sori occur near the fertile pinnule midvein and have flat indusia which resemble small saucers.
Alsophila amboinensis, synonym Cyathea amboinensis, is a species of tree fern native to the Maluku Islands and possibly central and southern Sulawesi, where it grows in swamp and forest at low elevations. This species has an erect trunk, usually 2–4 m tall. Fronds are 1–2 m long and bi- or tripinnate. The stipe is warty near the base and covered with scattered scales that are dark, glossy, and have fragile edges. Sori occur near the midvein of fertile pinnules and are covered by small, dark indusia which resemble small scales.
Alsophila aneitensis, synonym Cyathea aneitensis, is a species of tree fern native to Vanuatu and possibly New Caledonia. This species has an erect trunk up to 3 m tall. Fronds are bipinnate and may reach 2 m in length. The rachis and stipe are either very dark and smooth or have a few scales towards the base of the stipe. The scales are dark and narrow. Sori occur near the pinnule midvein and are covered by large, thin, fragile indusia. The closest relative of A. aneitensis appears to be Alsophila vieillardii. It can be distinguished from that species by its very dark stipes and frond bases.
Alsophila batjanensis, synonym Cyathea batjanensis, is a species of tree fern native to the Maluku Islands and western New Guinea, where it grows in rain forest at an altitude of approximately 600 m. The trunk is erect and 2–3 m tall. Fronds are bi- or tripinnate and 1–2 m long. The stipe is spiny, warty and covered with scattered scales that are dark brown and have fragile edges. Sori are round and occur near the fertile pinnule midvein. They are covered by small, narrow indusia that resemble small saucers in appearance.
Gymnosphaera biformis, synonyms Alsophila biformis and Cyathea biformis, is a species of tree fern native to New Guinea and the Maluku Islands, where it grows against trees in mossy forest and rain forest at elevations of 850–2200 m. The climbing trunk is very thin, only 1–2 cm in diameter, but can reach 3 m in height. The apex of the trunk is covered in scales. Two types of fronds are produced, simple pinnate fronds, which are sterile, and bipinnate fronds, which may be fertile. The stipe is smooth, glossy and very dark, almost to the point of being black. It is covered at the base with long, very dark scales that have a pale margin. Fertile pinnules are distinctly stalked and lobed. Sori occur in four pairs per pinnule lobe and lack indusia.
Alsophila borneensis, synonym Cyathea borneensis, is a species of tree fern native to southern parts of Thailand and Cambodia, as well as the Malay Peninsula and Borneo, where it grows in lowland forest at an altitude of 400–1100 m. The trunk is erect and usually up to 2 m tall or more. Fronds are bi- to tripinnate and 2–3 m long. The stipe is spiny and warty. It is covered with scattered scales that are dark, glossy and have narrow, fragile edges. Sori are close to fertile pinnule midveins and covered by thin indusia.
Alsophila brevipinna, synonym Cyathea brevipinna, is a species of tree fern endemic to the higher parts of Mount Gower on Lord Howe Island, where it grows in exposed areas at an altitude of about 790 m. The trunk is erect and may reach 3 m in height. It is often covered with reddish brown scales and stipe bases. This species may produce stolons at ground level. Fronds are tripinnate, densely crowded, and up to about 3 m long. The stipe is brown and sometimes warty after scales fall off. The scales are long, glossy dark brown, with a distinctly narrow apex and fragile paler edges. Sori are attached to deeply divided fertile pinnules that may uncurl over the sori. Indusia are firm and large. A. brevipinna is a stunted plant with short pinnae.
Alsophila caudata, synonym Cyathea caudata, is a species of tree fern native to the islands of Luzon and Mindanao in the Philippines, where it grows in montane forest. The trunk is erect and up to 4 m tall or more. Fronds are bi- or tripinnate and 1–2 m long. The stipe is warty and covered with dark, narrow, glossy scales. Sori are borne near the midvein of fertile pinnules and are protected by firm, brown indusia. As of April 2022, Plants of the World Online treated it as a synonym of Alsophila speciosa.
Alsophila costularis, synonyms Cyathea chinensis and Sphaeropteris chinensis, is a species of tree fern native to Yunnan in China, Sikkim in India, as well as Nepal, Myanmar, Laos and Vietnam. Plants grow in forest and montane forest at an altitude of 900–1800 m. The trunk is erect and 1–2 m tall. Fronds are bipinnate and 1–2 m long. The stipe is either long and warty or has short spines towards the base as well as scattered glossy dark brown scales with fragile edges. Sori occur near the midvein of fertile pinnules and are covered by thin indusia.
Alsophila hermannii, synonym Cyathea christiiCopel., is a species of tree fern endemic to Mindanao in the Philippines, where it grows in forest at an altitude of 900–1800 m. The trunk is erect and may be 5 m tall or more. Fronds are bi- or tripinnate and 2–3 m long. The stipe is covered with some warts and narrow, brown scales. Sori occur near the midvein of fertile pinnules and are covered by thin, fragile indusia.
Alsophila dryopteroides, synonym Cyathea dryopteroides, is a tree fern native to Puerto Rico, where it grows in shaded areas and cloud forests at an altitude of 1000–1200 m. The erect trunk may be 1.3 m tall and approximately 5 cm in diameter. Fronds are pinnate and up to 1.6 m long. The rachis is often purplish brown and covered with scales, usually on the underside. The scales range in colour from golden brown to bicoloured. Sori occur along each side of the pinnule midvein and indusia are cup-like.
Alsophila edanoi, synonym Cyathea edanoi, is a species of tree fern endemic to Luzon in the Philippines, where it grows in montane forest at an altitude of about 1300 m. The trunk is erect and 1–2 m tall. Fronds are bi- or tripinnate and approximately 1 m long. The stipe is covered in dark, glossy scales that have narrow, fragile edges. Sori occur near the midvein of fertile pinnules and are covered, sometimes half-covered, by large, firm, brown indusia.
Alsophila fenicis, synonym Cyathea fenicis, is a species of tree fern native to the Philippines, Taiwan, and Orchid Island, where it grows in wet forest, forest margins and on hillsides. The trunk is erect, up to 1 m tall and about 6 cm in diameter. Fronds are tripinnate and 1.5–2 m long. Characteristically of this species, the lowest pinnae are usually reduced. The stipe is spiny and ranges in colour from brown to purple-dark brown. It bears two types of scales: long dark brown scales as well as minute brown ones. Occasionally the scales are pale. Sori are round and arranged in two rows, one on either side of the pinnule midvein. They are covered by very small indusia that resemble scales in appearance.
Alsophila ferruginea, synonym Cyathea ferruginea, is a species of tree fern endemic to the Philippines. It is native to the islands of Negros, Palawan and Balabac. It grows in mossy forest up to an altitude of about 1,200 metres (3,900 ft).
Alsophila geluensis, synonym Cyathea geluensis, is a species of tree fern native to central and eastern New Guinea as well as the Louisiade Archipelago, where it grows in mossy forest. In New Guinea itself, plants grow at an altitude of 1000–2000 m, however they are present at lower elevations of 700–900 m on associated islands. The trunk of this tree fern is erect and may be 5 m tall or more. Fronds are bi- or tripinnate and 1–2.5 m long. They are usually about ten live fronds present in the crown at once. The stipe may be warty and/or have short spines as well as many scattered scales towards the base. These scales are pale to dark and have dull, fragile edges. Sori occur near the fertile pinnule midvein and are protected by pale, thin indusia. A. geluensis is a variable taxon and further study is needed to determine whether it does not in fact represent a species complex.
Alsophila halconensis, synonym Cyathea halconensis, is a species of tree fern native to the islands of Luzon and Mindoro in the Philippines, where it grows in forest at an altitude of 1200–1700 m. The trunk of this plant is erect and 2–4 m tall. Fronds may be bi- or tripinnate and more than 1 m in length. Conical spines and scales cover the stipe. These scales are dark brown in colouration and have fragile edges. Sori occur near the fertile pinnule midvein. They are protected by thin, pale indusia.
Alsophila hooglandii, synonym Cyathea hooglandii, is a species of tree fern native to the Western Highlands of New Guinea, where it grows in mossy forest at an altitude of about 3000 m. The trunk of this plant is erect, up to 3 m tall and approximately 10 cm in diameter. Fronds are tripinnate, 1–2 m in length and produced in two whorls of five to seven each. The stipe may be dull and warty or densely covered with scales. These scales range in colour from dark to medium brown and have a broad, paler margin as well as fragile edges. Perhaps the most distinguishing feature of this species are its sori, which are borne singly at the base of each tertiary pinnule on the midvein. They are protected by firm indusia that are saucer-like in appearance.
Gymnosphaera khasyana, synonyms Alsophila khasyana and Cyathea khasyana, is a species of tree fern. Its natural distribution extends from the Himalayas and eastern India to Myanmar and south-central China, although it is absent from Sri Lanka. G. khasyana grows in forest at an elevation of 1400–1700 m. The trunk of this plant is erect and 5–7 m tall. Fronds may be bi- or tripinnate and 2–3 m in length. G. khasyana has a long, dark stipe that is covered in numerous scales. These scales are dark and have broad, pale, fringed edges. Sori are borne near the midvein of fertile pinnules and lack indusia.
Alsophila brausei, synonym Cyathea hunsteiniana, is a species of tree fern endemic to eastern New Guinea, where it grows in rain forest at an altitude of 1300–2000 m. This species has a slender, erect trunk up to 1 m tall and about 3 cm in diameter. Fronds are bipinnate and approximately 1 m in length. Scattered scales cover the stipe. They are dark brown in colouration and have a broad paler margin and fragile edges. Round sori are borne one or two per fertile pinnule segment. The sori are protected by deep, firm indusia that are cup-like in appearance.
Alsophila crassicaula, synonym Cyathea ledermannii, is a species of tree fern native to Papua New Guinea and Bougainville Province in the Solomon Islands, where it is common in submontane rain forest at an altitude of 1000–3000 m. The trunk of this plant is erect and grows to about 3 m in height. Fronds may be bi- or tripinnate and up to 2 m in length. The rachis is purplish brown in colouration and usually bears basal scales. These scales range from pale, to brown, to bicoloured. Sori are borne on each side of the pinnule midvein. They are protected by firm indusia.
