Silene hawaiiensis is a rare species of flowering plant in the pink family

Caryophyllaceae

The Caryophyllaceae, commonly called the pink family or carnation family, is a family of flowering plants. It is included in the dicotyledon order Caryophyllales in the APG III system, alongside 33 other families, including Amaranthaceae, Cactaceae and Polygonaceae...

 known by the common names Hawaiian catchfly and Sherff's catchfly. It is endemic to Hawaii

Hawaii

Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

, where it is known only from the island of Hawaii

Hawaii (island)

The Island of Hawaii, also called the Big Island or Hawaii Island , is a volcanic island in the North Pacific Ocean...

. It is threatened by the degradation of its habitat and it is a federally listed threatened species of the United States.

This subshrub

Shrub

A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

 grows 15 to 40 centimeters tall and bears narrow leaves and greenish white flowers. The roots are spindle

Spindle

The term spindle may refer to:In textiles and manufacturing:*Spindle , a device to spin fibres into thread*Spindle , is the main rotating part of a machine tool, woodworking machine, etc...

-shaped and sometimes grow exposed aboveground, which may help the plant survive.

This plant grows on the lava

Lava

Lava refers both to molten rock expelled by a volcano during an eruption and the resulting rock after solidification and cooling. This molten rock is formed in the interior of some planets, including Earth, and some of their satellites. When first erupted from a volcanic vent, lava is a liquid at...

 and ash

Volcanic ash

Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...

 substrates of the volcanoes of the island of Hawaii. It grows at Kīlauea

Kilauea

Kīlauea is a volcano in the Hawaiian Islands, and one of five shield volcanoes that together form the island of Hawaii. Kīlauea means "spewing" or "much spreading" in the Hawaiian language, referring to its frequent outpouring of lava. The Puu Ōō cone has been continuously erupting in the eastern...

, Mauna Loa

Mauna Loa

Mauna Loa is one of five volcanoes that form the Island of Hawaii in the U.S. state of Hawaii in the Pacific Ocean, and the largest on Earth in terms of volume and area covered. It is an active shield volcano, with a volume estimated at approximately , although its peak is about lower than that...

, Mauna Kea

Mauna Kea

Mauna Kea is a volcano on the island of Hawaii. Standing above sea level, its peak is the highest point in the state of Hawaii. However, much of the mountain is under water; when measured from its oceanic base, Mauna Kea is over tall—significantly taller than Mount Everest...

, and Hualālai

Hualalai

Hualālai is a dormant shield volcano on the island of Hawaii in the Hawaiian Islands. It is the third-youngest and the third most active of the five volcanoes that form the island of Hawaii, following Kīlauea and the much larger Mauna Loa, and also the westernmost. Its peak is above sea...

. It is a member of the sparse flora in the southwest rift zone of Kilauea, which includes such plants as Coprosma ernodeoides (pilo), Dubautia ciliolata (naenae), Leptecophylla tameiameiae (pukiawe), Metrosideros polymorpha

Metrosideros polymorpha

The ōhia lehua is a species of flowering evergreen tree in the myrtle family, Myrtaceae, that is endemic to the six largest islands of Hawaii. It is a highly variable tree, being tall in favorable situations, and much smaller when growing in boggy soils or on basalt...

(ʻōhiʻa lehua), Nephrolepis exaltata (nianiau, ikupukupu), Sadleria

Sadleria

Sadleria is a genus of six species of ferns in the family Blechnaceae, all endemic to Hawaii.Species*Sadleria cyatheoides Kaulf. *Sadleria pallida Hook...

sp. (amau), and Vaccinium reticulatum

Vaccinium reticulatum

Vaccinium reticulatum, known as Ōhelo ai in Hawaiian, is a species of flowering plant in the heather family, Ericaceae, that is endemic to Hawaii. It grows at altitudes of on lava flows and freshly disturbed volcanic ash on Maui and Hawaii, and less commonly on Kauai, Oahu, and Molokai...

(ōhelo ʻai). A recent estimate is a total of 22 populations containing 8360 individuals.

Threats to the plant include fire in some areas. Fire also fosters the takeover of invasive plant species

Invasive species

"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....

 such as Pennisetum setaceum (fountain grass), which displaces native plants; the flammable fountain grass then increases the likelihood of more fire. Construction and other activities at Mauna Kea and the Pohakuloa Training Area

Pohakuloa Training Area

Pōhakuloa Training Area is located on the island of Hawaii in the high plateau between Mauna Loa, Mauna Kea and the Hualālai volcanic mountains...

 may threaten some plants. Introduced

Introduced species

An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...

 Mouflon sheep

Mouflon

The mouflon is a subspecies group of the wild sheep Ovis aries. Populations of Ovis aries can be partitioned into the mouflons and urials or arkars...

are a threat to this and other native plants. Insect damage and climate change may be threats as well.