''Gymnosphaera andersonii'',

synonyms A synonym is a word, morpheme, or phrase that means precisely or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are a ...

''Alsophila andersonii'' and ''Cyathea andersonii'', is a species of

tree fern Tree ferns are arborescent (tree-like) ferns that grow with a trunk (botany), trunk elevating the fronds above ground level, making them trees. Many extant tree ferns are members of the order Cyatheales, to which belong the families Cyatheaceae ( ...

native to the eastern Himalayas of India,

Bhutan Bhutan, officially the Kingdom of Bhutan, is a landlocked country in South Asia, in the Eastern Himalayas between China to the north and northwest and India to the south and southeast. With a population of over 727,145 and a territory of , ...

, and Tibet, Myanmar, and south-central

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

, where it grows in moist valleys and montane forest at an elevation of 300–1200 m. The trunk is erect and 6–10 m tall.

Frond A frond is 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. Other botanists allow the term frond to also apply to the lar ...

s are bi- or

tripinnate Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and in ...

and 2–3 m long. The entire plant is relatively dark in appearance; the

rachis In biology, a rachis (from the [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the ''rachi ...

is flushed with dark purple and the stipe is dark, almost to the point of being black. Dark, lanceolate scales with pale fringes are sparsely scattered along the length of the stipe. Sori occur near the midvein of fertile

pinnule A leaflet (occasionally called foliole) in botany is a leaf-like part of a compound leaf. Though it resembles an entire leaf, a leaflet is not borne on a main plant stem or branch, as a leaf is, but rather on a petiole or a branch of the leaf. C ...

s and lack indusia. The specific

epithet An epithet (, ), also a byname, is a descriptive term (word or phrase) commonly accompanying or occurring in place of the name of a real or fictitious person, place, or thing. It is usually literally descriptive, as in Alfred the Great, Suleima ...

''andersonii'' is thought to commemorate Thomas Anderson (1832-1870), a botanist and director of the

Calcutta Kolkata, also known as Calcutta (List of renamed places in India#West Bengal, its official name until 2001), is the capital and largest city of the Indian States and union territories of India, state of West Bengal. It lies on the eastern ba ...

botanical garden.

References

{{Taxonbar, from1=Q93275880, from2=Q11126592, from3=Q5197507 andersonii Ferns of India Flora of Assam (region) Flora of East Himalaya Flora of Myanmar Flora of South-Central China Flora of Tibet Plants described in 1869