''Chorizanthe robusta'' is a species of flowering plant in the buckwheat family. It is

endemic Endemism is the state of a species being found only 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 foun ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, where it is a rare, 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, inv ...

Description

''Chorizanthe robusta'' is variable in form, growing decumbent or erect and reaching a maximum length of half a meter. It is grayish in color and hairy. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is made up of several flowers with each flower surrounded by white or pink

bract In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also lo ...

s with hooked tips. The flower itself is just a few millimeters long and white to pink in color.

Varieties

It is composed of two varieties: *var. ''robusta'', known generally as the robust spineflower, which is known only from southern Santa Cruz and Monterey Counties, *var. ''hartwegii'', the Scotts Valley spineflower, which is known from a few locations in

Scotts Valley Scotts Valley is a small city in Santa Cruz County, California, United States, about south of downtown San Jose and north of the city of Santa Cruz, in the upland slope of the Santa Cruz Mountains. As of the 2020 census, the city populati ...

in Santa Cruz County.Flora of North America: var. ''hartwegii''
/ref> The plant is closely related to ''

Chorizanthe pungens ''Chorizanthe pungens'' is a species of flowering plant in the buckwheat family known by the common name Monterey spineflower. It is endemic to California, where it is known from the San Francisco Bay Area south along the Central Coast. Descri ...

'', another rare endemic from the area.

References

External links

Jepson Manual Treatment: ''Chorizanthe robusta''The Nature Conservancy: ''C. robusta''Photo gallery: ''C.robusta'' var. ''hartwegii''

robusta ROBUSTA (Radiation on Bipolar for University Satellite Test Application) is a nano-satellite scientific experiment developed by the University of Montpellier students as part of a Centre National d'Études Spatiales (CNES) call for student proje ...

Endemic flora of California Natural history of the California chaparral and woodlands Natural history of the San Francisco Bay Area Natural history of Santa Cruz County, California Plants described in 1889 {{Polygonaceae-stub