''Cyperus pennatiformis'' (formerly ''Mariscus pennatiformis'')USFWS
''Cyperus pennatiformis'' Five-year Review.
August 2010. is a rare species of

sedge The Cyperaceae are a family of graminoid (grass-like), monocotyledonous flowering plants known as sedges. The family is large, with some 5,500 known species described in about 90 genera, the largest being the "true sedges" genus ''Carex'' wit ...

known by the common name coastal flatsedge. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

, where it grows on the islands of

Maui The island of Maui (; Hawaiian: ) is the second-largest of the islands of the state of Hawaii at 727.2 square miles (1,883 km2) and is the 17th largest island in the United States. Maui is the largest of Maui County's four islands, which ...

Kauai Kauai, () anglicized as Kauai ( ), is geologically the second-oldest of the main Hawaiian Islands (after Niʻihau). With an area of 562.3 square miles (1,456.4 km2), it is the fourth-largest of these islands and the 21st largest island ...

, and

Laysan Laysan (; haw, italics=no, Kauō ), located northwest of Honolulu at , is one of the Northwestern Hawaiian Islands. It comprises one land mass of , about in size. It is an atoll of sorts, although the land completely surrounds a shallow ...

. It is a federally listed

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...

of the United States. This sedge grows 40 centimeters to 1.2 meters tall with leathery leaves as long as the stem or longer. The flower cluster atop the stem is

umbrella An umbrella or parasol is a folding canopy supported by wooden or metal ribs that is usually mounted on a wooden, metal, or plastic pole. It is designed to protect a person against rain or sunlight. The term ''umbrella'' is traditionally used ...

-shaped and up to 15 centimeters long by 25 wide. It contains up to 18 spikes which are each made up of several yellowish or grayish spikelets. The spikelet contains up to 25 flowers.USFWS
Endangered Status for 12 Plants From the Hawaiian Islands.
''Federal Register'' November 10, 1994. Today, this plant grows on

, and

; it has recently been

extirpated Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...

from

Oahu Oahu () (Hawaiian language, Hawaiian: ''Oʻahu'' ()), also known as "The Gathering place#Island of Oʻahu as The Gathering Place, Gathering Place", is the third-largest of the Hawaiian Islands. It is home to roughly one million people—over t ...

and the island of

. The most recent surveys found about 30 individual plants on Maui and four populations on Kauai; these represent the subspecies ''pennatiformis''. On Laysan the plants are of subspecies ''bryanii'', known as Laysan sedge or Bryan's sedge. In 2008, a total of 488 individuals were counted. The Laysan sedge, though rare, appears to be reproducing successfully. On Maui, the sedge grows on seaside cliffs where it is washed with ocean spray. The habitat is a type of coastal forest dominated by hala (''Pandanus tectorius''). On Kauai, it can be found in moist forested canyons. On Laysan, ssp. ''bryanii'' grows in

wetland A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...

s and

sand dunes A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, fl ...

.''Cyperus pennatiformis''.
The Nature Conservancy. This plant is threatened by a number of processes, chiefly

habitat destruction Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

and degradation by

feral A feral () animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some ...

ungulate Ungulates ( ) are members of the diverse clade Ungulata which primarily consists of large mammals with hooves. These include odd-toed ungulates such as horses, rhinoceroses, and tapirs; and even-toed ungulates such as cattle, pigs, giraffes, cam ...

s such as

pigs The pig (''Sus domesticus''), often called swine, hog, or domestic pig when distinguishing from other members of the genus '' Sus'', is an omnivorous, domesticated, even-toed, hoofed mammal. It is variously considered a subspecies of ''Sus s ...

and

goats The goat or domestic goat (''Capra hircus'') is a domesticated species of Caprinae, goat-antelope typically kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a membe ...

and the presence of non-native plants. The worst invasive plants include shoebutton (''Ardisia elliptica''),

lantana ''Lantana'' () is a genus of about 150 species of perennial flowering plants in the verbena family, Verbenaceae. They are native to tropical regions of the Americas and Africa but exist as an introduced species in numerous areas, especially in ...

(''Lantana camara''), yellow foxtail (''Setaria parviflora''), and Pride of India (''Melia azedarach''). On Laysan, this sedge and other plants were decimated by introduced rabbits. The seeds are eaten by the

Laysan finch The Laysan finch (''Telespiza cantans'') is a species of Hawaiian honeycreeper, that is endemic to the Northwestern Hawaiian Islands. It is one of four remaining finch-billed Hawaiian honeycreepers and is closely related to the smaller Nihoa finc ...

(''Telespiza cantans'').

References

External links

USDA Plants Profile
{{Taxonbar, from=Q5200208 pennatiformis Endemic flora of Hawaii Plants described in 1931

See also

References

External links