Cyathea hookeri is a species of tree fern

Cyatheales

The order Cyatheales is a taxonomic division of the fern subclass, Cyatheatae, which includes the tree ferns. No clear morphological features characterize all of the Cyatheales, but DNA sequence data indicates that the order is monophyletic. Some species in the Cyatheales have tree-like growth...

 endemic

Endemic (ecology)

Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...

 to Sri Lanka

Sri Lanka

Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

, where it grows in lowland forest. This plant has a narrow, erect trunk that is usually 1-2 m tall. Frond

Frond

The term frond refers to a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group...

s are pinnate

Pinnate

Pinnate is a term used to describe feather-like or multi-divided features arising from both sides of a common axis in plant or animal structures, and comes from the Latin word pinna meaning "feather", "wing", or "fin". A similar term is pectinate, which refers to a comb-like arrangement of parts...

 and approximately 1 m in length. The stipe

Stipe (botany)

In botany, a stipe is a stalk that supports some other structure. The precise meaning is different depending on which taxonomic group is being described....

 is dark and covered with blunt spines and scattered scale

Scale (zoology)

In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...

s. These scales are long, glossy, medium brown in colouration, and have fragile edges. Sori

Sorus

A sorus is a cluster of sporangia .In fungi and lichens, the sorus is surrounded by an external layer. In some red algae it may take the form of a depression into the thallus....

 are borne on the lowest one or two pairs of veins of fertile pinnules. They are protected by thin indusia.

The specific epithet

Epithet

An epithet or byname is a descriptive term accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, divinities, objects, and binomial nomenclature. It is also a descriptive title...

 hookeri commemorates botanist William Jackson Hooker

William Jackson Hooker

Sir William Jackson Hooker, FRS was an English systematic botanist and organiser. He held the post of Regius Professor of Botany at Glasgow University, and was the first Director of the Royal Botanic Gardens, Kew. He enjoyed the friendship and support of Sir Joseph Banks for his exploring,...

 (1785-1865), director of the Royal Botanic Gardens, Kew

Royal Botanic Gardens, Kew

The Royal Botanic Gardens, Kew, usually referred to as Kew Gardens, is 121 hectares of gardens and botanical glasshouses between Richmond and Kew in southwest London, England. "The Royal Botanic Gardens, Kew" and the brand name "Kew" are also used as umbrella terms for the institution that runs...

from 1841 until his death.