''Acaena exigua'' is an extinct species of flowering plant in the

rose family Rosaceae (), the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus ''Rosa''. Among the most species-rich genera are '' Alchemilla'' (270), ''Sorbus ...

known by the common name liliwai. It was

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 was known from

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 west

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 ...

. It had not been seen or collected since 1957 and was feared

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

until 1997, when one plant was discovered in a remote montane

bog A bog or bogland is a wetland that accumulates peat as a deposit of dead plant materials often mosses, typically sphagnum moss. It is one of the four main types of wetlands. Other names for bogs include mire, mosses, quagmire, and muskeg; a ...

on Maui.Records of the Hawaii Biological Survey for 1997, Part 2: Notes.
''Bishop Museum Occasional Papers'' 56, page 6. The plant died in 2000, and the species is now considered extinct.

Reason for extinction

The reason for extinction is unknown. While it has been ascribed to rooting by pigs, feral populations have only been present in the vicinity of the population on Kauai for some twenty years, and West Maui is pig-free.

References

External links

USDA Plants ProfileThe Nature Conservancy
exigua Endemic flora of Hawaii {{Rosoideae-stub