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.
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 buennemeijeri, synonym Cyathea buennemeijeri, is a species of tree fern endemic to the Natuna Islands in Indonesia. In the World Geographical Scheme for Recording Plant Distributions, these islands are treated as part of Kalimantan. A. buennemeijeri grows in open scrub at an altitude of about 600 m. This rare species is known only from the summits of two low hills. 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 dark and covered with spines at the base, as well as numerous scattered dark scales with pale, fragile edges. Sori occur near the midvein of fertile pinnules and are covered by thin, fragile indusia that resemble cups in shape.
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 doctersii, synonym Cyathea doctersii, is a species of tree fern endemic to Sumatra, where it grows in forest at an altitude of approximately 150 m. The trunk is erect and 2–3 m tall. Fronds are bi- or tripinnate and 2–3 m long. The stipe is covered with scattered flat, brown scales and some hairs. Sori occur near the fertile pinnule midvein and are covered by thin, brown indusia that are scale-like in appearance.
Alsophila dryopteroides, synonym Cyathea dryopteroides, is a tree fern native to Puerto Rico, where it grows where it grows in shaded areas and cloud forest 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 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.
Gymnosphaera gigantea, synonyms Alsophila gigantea and Cyathea gigantea, is a species of tree fern native to northeastern to southern India, Sri Lanka, Nepal to Myanmar, Thailand, Laos, Vietnam, the Malay Peninsula, as well as central Sumatra and western Java. It grows in moist open areas at an elevation of 600–1000 m. The trunk of this species is erect and may be as tall as 5 m or more. Fronds are bi- or tripinnate and usually 2–3 m long. The rachis is long, dark to black in colouration and rough in appearance after the fall of scales. These scales are dark brown, glossy and have a narrow paler margin and fragile edges. Sori are round and indusia absent.
Alsophila gleichenioides, synonym Cyathea gleichenioides, is a species of tree fern endemic to New Guinea, where it grows in open peaty grassland and on forest margins, often in groups, at an altitude of 2800–3700 m. The trunk of this plant is erect, up to 3 m tall and about 24 cm in diameter. The narrow fronds are tripinnate and about 1 m in length. Around 60 fronds form a rounded crown. The stipe is warty and bears scattered scales towards the base. These scales may be either glossy brown with a paler dull margin, or small, pale and fringed. Sori occur one or two per fertile pinnule and are protected by firm, brown indusia.
Alsophila × marcescens, synonym Cyathea × marcescens, commonly known as the skirted tree fern, is a tree fern endemic to the Cape Otway ranges in Victoria and Tasmania, Australia. It is a natural hybrid, apparently Alsophila australis × Alsophila cunninghamii. Large and Braggins (2004) note that it has characteristics midway between these two species. The spores of A. × marcescens are usually malformed although sterile. The trunk of this plant is erect and up to 10 m tall. Fronds may be bi- or tripinnate and 3–4 m in length. Dead fronds often persist, forming a characteristic skirt around the trunk. The stipe is thick, black and warty. The rachis and trunk are covered in shiny, dark brown scales. Sori are borne near the fertile pinnule midvein and are protected by thin indusia that are saucer-like in appearance.
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 imbricata, synonym Cyathea imbricata, is a species of tree fern endemic to Western New Guinea, where it grows in open forest at an altitude of 3240 m. The trunk of this plant is erect and approximately 2 m tall. Fronds may be bi- or tripinnate and are usually less than 1 m in length. The stipe is dark, spiny, and covered with caducous scales. These scales are glossy brown in colouration and have a paler margin and fragile edges. Sori are borne in groups of one to four per pinnule lobe. They are protected by firm indusia.
Alsophila incisoserrata, synonym Cyathea incisoserrata, is a species of tree fern native to the Malay Peninsula and the state of Sarawak on the island of Borneo, where it grows in forest and forest margins from the lowland to approximately 1250 m. The trunk is erect, about 4 m tall and 12 cm in diameter. Fronds may be bi- or tripinnate and 1–2 m in length. The stipe of this species is partly persistent and is sometimes retained on the upper trunk. It is warty, bears conical spines, and is sparsely covered with scales. These scales may be either small and fringed or bullate. Sori are borne near the fertile pinnule midvein. They are protected by very small, often bilobed indusia.
Alsophila javanica, synonym Cyathea javanica, is a species of tree fern native to western Java and Sumatra, in Indonesia. It grows in rain forest and on riverbanks at an altitude of 250–1500 m.
Alsophila junghuhniana, synonym Cyathea junghuhniana, is a species of tree fern native to southern and central Sumatra and western Java, where it grows in forest at an altitude of 1000–2000 m. The trunk of this species is erect and may be 2 m tall or more. Fronds are tripinnate and up to about 3 m long. The stipes of this species are persistent and form a skirt around the trunk. They are brown, spiny, and covered with glossy, dark brown scales. Sori are borne near the midvein of fertile pinnules and are protected by thin indusia.
Alsophila arfakensis, synonym Cyathea kanehirae, is a species of tree fern native to western New Guinea, where it grows in montane forest at an altitude of 1600–2700 m. The trunk of this plant is erect and 1–4 m tall. Fronds may be bi- or tripinnate and 1–2 m in length. The rachis is smooth, while the stipe is dark and warty. The stipe is covered with flat, brown, scattered scales. Sori are borne near the fertile pinnule midvein. They are protected by small indusia that are cup-like in appearance.
Alsophila latebrosa, synonym Cyathea latebrosa, is a common and widespread species of tree fern native to Indochina. Its natural range covers Cambodia and Thailand, and stretches from the Malay Peninsula to Indonesia, where it is present on the islands of Borneo and Sumatra. Plants reported from India and Sri Lanka have thinner indusia and may represent a separate, as-yet undescribed, species. A. latebrosa grows in a wide range of habitats, including forest, secondary forest, and plantations, from sea level up to an elevation of about 1500 m.
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.
