''Pneumatopteris truncata'', also known as the Christmas Island fern, is a species of

terrestrial Terrestrial refers to things related to land or the planet Earth, as opposed to extraterrestrial. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on o ...

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

in the

Thelypteridaceae Thelypteridaceae is a family of about 900 species of ferns in the order Polypodiales. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is placed in the suborder Aspleniineae. Alternatively, the family may be submerged in a ...

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Description

The species grows as a large upright fern with 80–120 cm long fronds.

Distribution and habitat

The species is found in various sites in Asia, including India, southern China and Indochina. It also occurs on

Christmas Island Christmas Island, officially the Territory of Christmas Island, is an States and territories of Australia#External territories, Australian external territory in the Indian Ocean comprising the island of the same name. It is about south o ...

, an

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

territory A territory is an area of land, sea, or space, belonging or connected to a particular country, person, or animal. In international politics, a territory is usually a geographic area which has not been granted the powers of self-government, ...

in the eastern

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

, where it inhabits permanently moist sites in deep shade. The extremely small Christmas Island population has been listed as

Critically Endangered An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...

under Australia's

EPBC Act The ''Environment Protection and Biodiversity Conservation Act 1999'' (Cth) is an Act of the Parliament of Australia that provides a framework for protection of the Australian environment, including its biodiversity and its natural and cult ...

References

truncata Ferns of Asia Flora of Christmas Island Ferns of Australia Taxa named by Jean Louis Marie Poiret Plants described in 1804 {{Polypodiales-stub