Cyathea is a large genus of tree ferns comprising over 470 species, and is the type genus of the fern order Cyatheales, placed within the family Cyatheaceae. The genus was described by the English botanist James Edward Smith in 1793, published in the Mémoires de l'Académie des Sciences de Turin.
Species of Cyathea are mostly terrestrial ferns characterised by a single erect trunk that can reach several metres in height, though a minority of species produce branched or creeping stems. Many species develop a dense fibrous mass of adventitious roots at the trunk base, which helps anchor the plant and may absorb moisture. Fronds are typically large and pinnately divided. On the underside of fertile fronds, the spore-bearing structures (sori) are sheltered within small cup-shaped indusia — a feature reflected in the genus name, derived from the Greek kyatheion, meaning "little cup".
The genus has a pantropical distribution, with species occurring across tropical and subtropical regions of the Americas, Africa, Asia, and Oceania, as well as extending into temperate woodlands in some areas. Habitats range from lowland tropical rain forests to montane cloud forests and temperate fern-dominated woodlands.
Etymology
The name Cyathea is derived from the Greek kyatheion, meaning "little cup", a reference to the distinctively cup-shaped indusia (sori coverings) found on the underside of the fronds. The genus was formally described by James Edward Smith in 1793.
Distribution
Cyathea has a pantropical distribution, with species found across tropical and subtropical regions of the Americas, Africa, Asia, and Oceania. Members of the genus grow in a variety of habitats, from lowland tropical rain forests to montane cloud forests and temperate woodlands.
Taxonomy Notes
Cyathea is the type genus of the order Cyatheales and the family Cyatheaceae. It was described by J.E. Smith in 1793 (Mém. Acad. Turin 5: 4). The GBIF backbone recognises 468 accepted descendants. Two fossil species are known: †Cyathea cranhamii and †Cyathea inequilateralis (Eocene, North American west coast).
