Cyathea alleniae is a species of tree fern native to the Malay Peninsula, where it grows in forest margin on steep ground at an altitude of approximately 1200 m. The trunk is erect, about 4 m tall and 15 cm in diameter. It is usually unbranched, but may branch to form several small crowns. Fronds are bi- or tripinnate and 1–2 m long. The stipe is spiny at the base and at least partially covered by scales. Typically of section Alsophila, these scales are dark brown, glossy, and have fragile edges. Sori occur near the midvein of fertile pinnules and are covered by firm, brown indusia that resemble scales in appearance.
Cyathea alpicola is a species of tree fern native to central Sumatra, where it grows in montane rain forest at an altitude of 2000–2750 m. The erect trunk can reach 5 m or more in height. Fronds are bi- or tripinnate and usually 2–3 m long. They have a tendency to persist on the plant after withering, forming an irregular skirt around the trunk. This species has a spiny stipe, which is covered with a woolly layer of scales. There appear to be two forms with different scales; either dark glossy brown with a broad paler margin and fragile edges, or small, brown and finely fringed. Sori are covered by thin, fragile indusia and occur near the midvein of fertile pinnules. The closest relative of C. alpicola is thought to be Cyathea polycarpa, which differs by lacking spines altogether. Cyathea macropoda and Cyathea magnifolia may also be closely allied with this species.
Cyathea approximata is a species of tree fern endemic to Madagascar. The trunk is erect, spiny and about 2 m tall. Fronds are bipinnate and usually 2 m long. They often form a crown of two whorls of about seven fronds each. Dark brown scales with a paler margin cover the stipe. Sori are round and occur near the fertile pinnule midvein. They are covered by thin, brown indusia, which are cup-like in appearance.
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 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. C. brevipinna is a stunted plant with short pinnae.
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 costulisora is a species of tree fern native to Sumatra. The trunk is erect and usually 1–4 m tall. Fronds are bi- or tripinnate and 1–2 m long. The stipe is covered with warts and scales. The scales are either pale and glossy or dark and flat. Sori occur near the fertile pinnule midvein and are covered by large, 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 deckenii is a species of tree fern native to the Democratic Republic of the Congo, Tanzania and Mozambique, where it grows in wet forest at an altitude of 1350–2300 m. The trunk is erect and up to 10 m tall. Fronds are bipinnate and 2–3 m long. Characteristically of this species, the most basal one or two pairs of pinnae are reduced. The rachis and stipe range in colour from brown to dark brown or black-brown and are sparsely covered with a few scales. The scales are dark and narrow with a fragile margin of variable width. The stipe also has conical warts near the base. Sori are round and covered by large, thin indusia.
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.
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.
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 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 kermadecensis is a species of tree fern endemic to Raoul Island in the Kermadec Islands, where it is locally common in damp, and sometimes drier, forest and scrub. The trunk of this plant is erect, slender, and up to 20 m tall. It is often covered with scars of old stipe-bases. Fronds are tripinnate and up to 4 m in length. The rachis and stipe are both brown in colouration and bear basal scales that are brown, glossy, and often twisted. Sori are borne on either side of the pinnule midvein. They are covered by hood-like indusia.
