''Isodendrion laurifolium'' is a rare species of flowering plant in the violet family known by the common names rockcliff isodendrion and ''aupaka''. 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 is known from fewer than 1000 individuals on the islands of

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

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 ...

.''Isodendrion laurifolium''.
The Nature Conservancy. 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.

Description

This is a

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

growing 1 to 2 meters tall. It produces purple flowers. It has very few branches. The leathery leaves are from 4-16 centimeters long. The flowers are borne along the stems. The five clawed petals are purple with white edges. The fruit is a green capsule. The flowers are bisexual, meaning that they have both male and female flowers. The stipules are

glabrous Glabrousness (from the Latin ''glaber'' meaning "bald", "hairless", "shaved", "smooth") is the technical term for a lack of hair, down, setae, trichomes or other such covering. A glabrous surface may be a natural characteristic of all or part of ...

ciliate The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to flagellum, eukaryotic flagella, but are in general shorter and present in much larger numbers, with a ...

. The bottom flower petals are slightly longer than the others.

Habitat

This shrub only grows in moist and wet forest habitat. As of 2003 there were five occurrences of the plant on Oahu for a total of 22 or 23 individuals in the

Waianae Waianae () is a census-designated place (CDP) in Honolulu County, Hawaii, United States. As of the 2020 census, the CDP population was 13,614. Its name means "waters of the mullet". Its etymology is shared with the far northern Wellington subu ...

and Koolau Mountains. In Kauai there were thirteen occurrences with 142 to 154 plants. Only one population of the plant has more than 50 individuals.USFWS
''Isodendrion laurifolium'' Five-year Review.
July 2009. The plants' habitat is threatened 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 including

wild boars The wild boar (''Sus scrofa''), also known as the wild swine, common wild pig, Eurasian wild pig, or simply wild pig, is a Suidae, suid native to much of Eurasia and North Africa, and has been introduced to the Americas and Oceania. The speci ...

. Another threat is competition with non-native plant species.

References

External links

''Isodendrion'' photo gallery
laurifolium Endemic flora of Hawaii {{Violaceae-stub