Euphorbia eleanoriae
Encyclopedia
Euphorbia eleanoriae is a rare species of flowering plant in the euphorb family
known by the common name Nā Pali sandmat. It is endemic to Kauai
, Hawaii
. Like other native Hawaiian euphorbs it is called akoko locally. This plant was only discovered in 1992 and described to science in 1996 as Chamaesyce eleanoriae. At that time there were fewer than 500 plants known, all occurring in small populations scattered across the sheer cliffs along the Nā Pali Coast
of Kauai. By 2001 the total population had already dropped; only three populations were found, for a total of fewer than 50 plants. The plant was federally listed as an endangered species
of the United States in 2010.
This is a shrub
growing up to about 40 centimeters in maximum height. It is intricately branched into brittle red or green twigs. The leaves have oval blades up to 2 centimeters long by 1.4 wide, and pale green in color with reddish edges. The inflorescence
is a small cyathium
about 3 millimeters long with white appendages each less than 3 millimeters wide.
This rare plant grows on basalt
cliffs and other windy coastal rocky slopes at elevations between 270 and 1036 meters. It inhabits mesic forests dominated by ōhia lehua
(Metrosideros polymorpha) and lama
(Diospyros sandwicensis), M. polymorpha-dominated cliff-side and mesic shrublands, and dry
cliffs dominated by kāwelu (Eragrostis variabilis). Threats to its existence include feral goat
s and invasive plant species
such as Santa Barbara daisy
(Erigeron karvinskianus), airplant
(Kalanchoe pinnata), and lantana
(Lantana camara). Many plants were destroyed by Hurricane Iniki
in 1992.
Euphorbiaceae
Euphorbiaceae, the Spurge family are a large family of flowering plants with 300 genera and around 7,500 species. Most are herbs, but some, especially in the tropics, are also shrubs or trees. Some are succulent and resemble cacti....
known by the common name Nā Pali sandmat. It is endemic to Kauai
Kauai
Kauai or Kauai, known as Tauai in the ancient Kaua'i dialect, is geologically the oldest of the main Hawaiian Islands. With an area of , it is the fourth largest of the main islands in the Hawaiian archipelago, and the 21st largest island in the United States. Known also as the "Garden Isle",...
, 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...
. Like other native Hawaiian euphorbs it is called akoko locally. This plant was only discovered in 1992 and described to science in 1996 as Chamaesyce eleanoriae. At that time there were fewer than 500 plants known, all occurring in small populations scattered across the sheer cliffs along the Nā Pali Coast
Na Pali Coast State Park
Nā Pali Coast State Park encompasses of land and is located in the center of the rugged along the northwest side of Kauai, the oldest inhabited Hawaiian island. The Nā Pali coast itself extends southwest starting at Kee Beach extending all the way to Polihale State Park. The pali rise as high as...
of Kauai. By 2001 the total population had already dropped; only three populations were found, for a total of fewer than 50 plants. The plant was federally listed as an endangered species
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
of the United States in 2010.
This is a shrub
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...
growing up to about 40 centimeters in maximum height. It is intricately branched into brittle red or green twigs. The leaves have oval blades up to 2 centimeters long by 1.4 wide, and pale green in color with reddish edges. The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
is a small cyathium
Cyathium
A cyathium is one of the specialised pseudanthia forming the inflorescence of plants in the genus Euphorbia . A cyathium consists of:...
about 3 millimeters long with white appendages each less than 3 millimeters wide.
This rare plant grows on basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
cliffs and other windy coastal rocky slopes at elevations between 270 and 1036 meters. It inhabits mesic forests dominated by ōhia lehua
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...
(Metrosideros polymorpha) and lama
Diospyros sandwicensis
Diospyros sandwicensis is a species of flowering tree in the ebony family, Ebenaceae, that is endemic to Hawaii. Its common name, Lama, also means enlightenment in Hawaiian. Lama is a small to medium-sized tree, with a height of and a trunk diameter of . It can be found in dry, coastal mesic,...
(Diospyros sandwicensis), M. polymorpha-dominated cliff-side and mesic shrublands, and dry
Hawaiian tropical dry forests
The Hawaiian tropical dry forests are a tropical dry broadleaf forest ecoregion in the Hawaiian Islands. They cover an area of on the leeward side of the main islands and the summits of Niihau and Kahoolawe. These forests are either seasonal or sclerophyllous. Annual rainfall is less than and...
cliffs dominated by kāwelu (Eragrostis variabilis). Threats to its existence include feral goat
Feral goat
The feral goat is the domestic goat when it has become established in the wild. Feral goats occur in Australia, New Zealand, Ireland, Great Britain, Hawaii, the Galapagos and in many other parts of the world...
s and 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 Santa Barbara daisy
Erigeron karvinskianus
Erigeron karvinskianus is a species of flowering plant in the daisy family known by the common name Latin American fleabane, though some know it as the Santa Barbara daisy....
(Erigeron karvinskianus), airplant
Kalanchoe pinnata
Kalanchoe pinnata is a succulent plant native to Madagascar...
(Kalanchoe pinnata), and lantana
Lantana camara
Lantana camara, also known as Spanish Flag or West Indian Lantana, is a species of flowering plant in the verbena family, Verbenaceae, that is native to the American tropics. It has been introduced into other parts of the world as an ornamental plant and is considered an invasive species in many...
(Lantana camara). Many plants were destroyed by Hurricane Iniki
Hurricane Iniki
Hurricane Iniki was the most powerful hurricane to strike the U.S. state of Hawaii in recorded history. Forming on September 5 during the strong El Niño of 1991–1994, Iniki was one of eleven Central Pacific tropical cyclones during the 1992 season. It attained tropical storm status on...
in 1992.