Sibara filifolia
Encyclopedia
Sibara filifolia, known by the common name Santa Cruz Island winged rockcress, is a rare species of flowering plant in the mustard family
. It is endemic to the Channel Islands of California
, where it is now known from a few occurrences on San Clemente Island
and one population on Catalina Island.
It was once present on Santa Cruz Island
, and perhaps other Channel Islands, but these occurrences were extirpated
by feral goat
s and pigs. The plant was feared extinct
until small remaining occurrences were discovered in 1986. A 1995 estimate of the total remaining population was 500 individuals. The plant became a federally listed endangered species
of the United States in 1997, along with Cercocarpus traskiae
and Lithophragma maximum
, two other rare Channel Islands plants.
up to 4 centimeters long containing tiny seeds.
of two islands off the coast of southern California
.
Brassicaceae
Brassicaceae, a medium sized and economically important family of flowering plants , are informally known as the mustards, mustard flowers, the crucifers or the cabbage family....
. It is endemic to the Channel Islands of California
Channel Islands of California
The Channel Islands of California are a chain of eight islands located in the Pacific Ocean off the coast of Southern California along the Santa Barbara Channel in the United States of America...
, where it is now known from a few occurrences on San Clemente Island
San Clemente Island
San Clemente Island is the southernmost of the Channel Islands of California. It is owned and operated by the United States Navy, and is a part of Los Angeles County. Defined by the United States Census Bureau as Block Group 2 of Census Tract 5991 of Los Angeles County, California, it is long and...
and one population on Catalina Island.
It was once present on Santa Cruz Island
Santa Cruz Island
Santa Cruz Island was the largest privately owned island off the continental United States, but is currently part-owned by the National Park service . The island, located off the coast of California, is long and from wide...
, and perhaps other Channel Islands, but these occurrences were extirpated
Local extinction
Local extinction, also known as extirpation, is the condition of a species which ceases to exist in the chosen geographic area of study, though it still exists elsewhere...
by 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 pigs. The plant was feared extinct
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally 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 recover may have been lost before this point...
until small remaining occurrences were discovered in 1986. A 1995 estimate of the total remaining population was 500 individuals. The plant became a federally listed 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 1997, along with Cercocarpus traskiae
Cercocarpus traskiae
Cercocarpus traskiae, known by the common names Santa Catalina Island mountain-mahogany and Catalina mahogany, is a rare species of plant in the rose family. It is endemic to the Channel Islands of California in the United States, where it is known from just a single population...
and Lithophragma maximum
Lithophragma maximum
Lithophragma maximum, known by the common name San Clemente Island woodland star, is a rare species of flowering plant in the saxifrage family. It is endemic to San Clemente Island, one of the eight Channel Islands of California. It is known from only about four kilometers of rocky coastal cliffs...
, two other rare Channel Islands plants.
Description
Sibara filifolia is an annual herb producing a hairless, sometimes waxy stem up to about 30 centimeters in maximum height. The leaves are very narrow, almost strandlike, measuring less than a millimeter wide, and growing about 1.5 centimeters long. The flowers each have four spoon-shaped lavender petals a few millimeters long. The fruit is a flattened, elongated siliqueSilique
A silique or siliqua is a fruit of 2 fused carpels with the length being more than three times the width. The outer walls of the ovary usually separate when ripe, leaving a persistent partition...
up to 4 centimeters long containing tiny seeds.
Distribution and habitat
Sibara filifolia grows in the coastal sage scrubCoastal sage scrub
Coastal sage scrub is a low scrubland plant community found in the California chaparral and woodlands ecoregion of coastal California and northern Baja California. It is characterized by low-growing aromatic, and drought-deciduous shrubs adapted to the semi-arid Mediterranean climate of the...
of two islands off the coast of southern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
.