''Sibara filifolia'', the Santa Cruz Island winged rockcress or Santa Cruz Island rockcress, is a rare species of flowering plant in the family

Brassicaceae Brassicaceae () or (the older) Cruciferae () is a medium-sized and economically important family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous plants, while some are shrubs. The l ...

. 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 els ...

to the

Channel Islands of California The Channel Islands () are an eight-island archipelago located within the Southern California Bight in the Pacific Ocean, off the coast of California. The four Northern Channel Islands are part of the Transverse Ranges geologic province, ...

, where it is now known from a few occurrences on

San Clemente Island San Clemente Island (Tongva: ''Kinkipar''; Spanish: ''Isla de San Clemente'') 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. It is administered b ...

and one population on Catalina Island.McGlaughlin, M. E., L. E. Wallace, and K. Helenurm. (2008)
Isolation of microsatellite loci from the endangered plant ''Sibara filifolia'' (Brassicaceae).
''Molecular Ecology Resources'' 8 367-69. It was once present on

Santa Cruz Island Santa Cruz Island ( Spanish: ''Isla Santa Cruz'', Chumash: ''Limuw'') is located off the southwestern coast of Ventura, California, United States. It is the largest island in California and largest of the eight islands in the Channel Islands ...

, and perhaps other Channel Islands, but these occurrences were

extirpated Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...

feral goat The feral goat is the domestic goat (''Capra aegagrus hircus'') when it has become established in the wild. Feral goats occur in many parts of the world. Species Feral goats consist of many breeds of goats, all of which stem from the wild goa ...

s and

pigs The pig (''Sus domesticus''), often called swine, hog, or domestic pig when distinguishing from other members of the genus ''Sus'', is an omnivorous, domesticated, even-toed, hoofed mammal. It is variously considered a subspecies of ''Sus ...

.Center for Plant Conservation
/ref> The plant was feared extinct until small remaining occurrences were discovered in 1986.California Native Plant Society Rare Plant Profile
/ref> 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 ''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. Distribution It is endemic to Catalina Island, one of the southern Channel Islands ...

'' and ''

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 ...

'', two other rare Channel Islands plants.USFWS
Determination of endangered status for three plants from the Channel Islands of California.
''Federal Register'' 62:153 August 8, 1997.

Description

''Sibara filifolia'' is an annual herb producing a hairless, sometimes waxy stem up to around 30 centimeters in maximum height. The leaves are very narrow and 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

silique A silique or siliqua (plural ''siliques'' or ''siliquae'') is a type of fruit (seed capsule) having two fused carpels with the length being more than three times the width. When the length is less than three times the width of the dried fruit ...

up to 4 centimeters long containing tiny seeds.

Distribution and habitat

''Sibara filifolia'' grows in the

coastal sage scrub Coastal sage scrub, also known as coastal scrub, CSS, or soft chaparral, is a low scrubland plant community of the California coastal sage and chaparral subecoregion, found in coastal California and northwestern coastal Baja California. It is ...

of two islands off the coast of southern

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the ...

References

External links

Jepson Manual TreatmentUSDA Plants ProfileFlora of North AmericaPhoto gallery
Brassicaceae Endemic flora of California Natural history of the California chaparral and woodlands Natural history of the Channel Islands of California Plants described in 1887 {{Brassicales-stub