The Cyatheaceae are the scaly tree fern family and include the world's tallest tree ferns, which reach heights up to 20 m. They are also very ancient plants, appearing in the fossil record in the late Jurassic, though the modern genera likely appeared in the Cenozoic. Cyatheaceae are the largest family of tree ferns, including about 500 species. Cyatheaceae and Dicksoniaceae, together with Metaxyaceae and Cibotiaceae, are a monophyletic group and constitute the "core tree ferns". Cyatheaceae are leptosporangiate ferns, the most familiar group of monilophytes.
Cyathea archboldii is a species of tree fern native to New Guinea and Bougainville, where it is common in submontane rain forest at an altitude of 1000–3000 m. The trunk is erect and up to about 3 m tall. Fronds are bipinnate and 2–3 m long. The rachis may be purplish and has short spines and scales. The scales range in colour from pale to brown, to bicoloured and have fragile edges. Sori occur in two rows along each side of the pinnule midvein and are covered by firm indusia.
Cyathea brooksii is a species of tree fern native to Cuba, Hispaniola and Puerto Rico, where it grows on serpentine soils in shaded ravines, along streams, and on forested slopese at an altitude of 250–950 m. The trunk is prostrate and only about 6 cm in diameter. Fronds are pinnate or bipinnate and up to 2 m long. The base of the rachis is covered with blackish scales that have a paler margin. Sori occur in two rows, one along each side of the pinnule midvein.
Cyathea bryophila is a species of tree fern native to Puerto Rico, where it grows in the understory in wet montane and mossy forest at an altitude of 750–1200 m. The trunk is erect, up to 7 m tall and about 10 cm in diameter. Fronds are pinnate or bipinnate and grow to 2 m in length. The underside of the rachis is pubescent and has occasional scales towards the base. The scales range in colour from brown to bicoloured. Sori occur along each side of the pinnule midvein and are covered by scale-like indusia. C. bryophila is a slow growing species, reportedly only increasing in trunk height by 5 cm a year, a growth rate more akin to that of Dicksonia species. It has been estimated that plants may live in excess of 150 years.
Cyathea capensis is a regionally widespread and highly variable species of tree fern. It is indigenous to Southern Africa and South America.
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.
Cyathea cunninghamii, also known as the gully tree fern and slender tree fern, is a species of tree fern indigenous to New Zealand including North Island, South Island and Chatham Islands; also to Victoria, possibly New South Wales, southeastern Queensland and Tasmania in Australia. It grows in damp forest, often emerging from stream gullies and riverbanks. Brownsey noted that it has a lower tolerance for drought than other species of Cyathea. The erect trunk may be 20 m tall and is usually 6–15 cm in diameter, occasionally as much as 20 cm. Fronds are tri- to tetrapinnate and 3 m or more in length. The rachis and stipe are slender, black brown, warty and covered with brown scales. Sori occur along each side of the pinnule midvein and are covered by hood-like indusia. C. cunninghamii is an uncommon and slow-growing tree fern.
Cyathea dregei is a widespread species of tree fern in southern Africa.
Cyathea esmeraldensis is a species of tree fern which is endemic to Ecuador. It grows in coastal forest and forested slopes of the Andes.
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.
Cyathea squamulata is a species of tree fern native to the Malay Peninsula, Sumatra, Java, Borneo and the southern Philippines, including the Sulu Archipelago, where it grows in forest from the lowlands to an altitude of about 1500 m. The trunk is erect and up to 2 m tall. Fronds are pinnate or bipinnate and approximately 1.5 m long. The stipe is covered in densely packed firm, medium brown scales. Sori occur near the fertile pinnule midvein and lack indusia.
Cyathea glabra is a species of tree fern native to Borneo, western Java, Sumatra and the Malay Peninsula, where it grows in lowland swamp forest and montane forest at an elevation of up to 1500 m. The trunk of this plant is erect and 2–4 m tall. Fronds are bi- or tripinnate and 1–2 m in length. Characteristically of this species, the lowest pinnae may be significantly reduced. The stipe is very dark and bears basal scales. These scales are dark, glossy and have a paler margin and fragile edges. Sori are produced in groups of one to three on fertile pinnule veins. They lack indusia.
Cyathea hancockii is a species of tree fern native to the Ryukyu Islands, Japan, Taiwan and Hong Kong. The specific epithet hancockii commemorates William Hancock (1847-1914), who collected numerous plants in Japan, China and Southeast Asia. It grows in forest, on stream banks, and in forest margins at an elevation of about 600 m or higher.
Cyathea propinqua is a species of tree fern native to Fiji and possibly Samoa, where it grows in wet forest. The trunk of this plant is erect and slender, growing to 10 m in height. Fronds may be bi- or tripinnate and 2–3 m long. Dull brown scales cover the dull, dark stipe of this species. The scales are minute along most of its length, becoming thick and fleshy towards the base. Sori are borne halfway between the pinnule midvein and the edge of the lobe. Indusia are present.
Cyathea metteniana is a species of tree fern native to the Ryukyu Islands, Japan, and Taiwan, where it grows in wet forest, forest margins, and on hillsides. The trunk of this plant is erect, up to 1 m tall, and 6–10 cm in diameter. C. metteniana has tripinnate fronds that are 1-2.5 m long. The stipe is brown to purple-black in colouration. It is covered in long, broad-based scales that are usually bicoloured. Sori are round, lack indusia, and occur in two rows, one on either side of the pinnule midvein.
Cyathea hotteana is a species of tree fern endemic to Haiti, where it grows in cloud forest at an altitude of 1000–1200 m. The trunk of this plant is erect, up to 2 m tall, and approximately 8 cm in diameter. Fronds are pinnate and may reach 2 m in length. Brown basal scales cover the rachis and stipe, which are also brown. Sori are borne in two rows, one on each side of the pinnule midvein. They are covered by shallow, plate-like indusia, which bear one or two clefts at the margin.
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.
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.
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. C. 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.
Cyathea smithii, commonly known as the soft tree fern or kātote, is a species of tree fern from New Zealand.
