''Streptanthus hispidus'', the Mt. Diablo jewelflower, is a rare species of flowering plant in the

mustard family 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 le ...

Distribution

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 elsew ...

Contra Costa County, California ) of the San Francisco Bay , subdivision_type = Country , subdivision_name = United States , subdivision_type1 = State , subdivision_name1 = California , subdivision_type2 ...

, where it is known from fewer than 15 occurrences on and around

Mount Diablo Mount Diablo is a mountain of the Diablo Range, in Contra Costa County, California, Contra Costa County of the eastern San Francisco Bay Area in Northern California. It is south of Clayton, California, Clayton and northeast of Danville, Califo ...

. It grows in rocky outcrops in

grassland A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...

and

chaparral Chaparral ( ) is a shrubland plant community and geographical feature found primarily in the U.S. state of California, in southern Oregon, and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterranean c ...

habitat. It is threatened by habitat degradation, such as trampling by

hikers Hiking is a long, vigorous walk, usually on trails or footpaths in the countryside. Walking for pleasure developed in Europe during the eighteenth century.AMATO, JOSEPH A. "Mind over Foot: Romantic Walking and Rambling." In ''On Foot: A Histor ...

and destruction during maintenance activities.The Nature Conservancy
/ref>

Description

''Streptanthus hispidus'' is a bristly annual herb growing up to 30 centimeters tall. Flowers occur in a

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

, the uppermost ones often sterile and different in form. The bristly bell-shaped calyx of

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

s is greenish brown in the fertile flowers and purple in the sterile. Fertile flowers have four light purple petals up to a centimeter long. The fruit is a bristly

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 i ...

up to 8 centimeters in length.

References

External links

Calflora Database: ''Streptanthus hispidus'' (Mt. Diablo jewelflower)

Jepson Manual eFlora (TJM2) treatment of ''Streptanthus hispidus''

* ttp://calphotos.berkeley.edu/cgi/img_query?query_src=photos_index&where-taxon=Streptanthus+hispidus U.C. Photos gallery of ''Streptanthus hispidus'' images hispidus Endemic flora of California Mount Diablo Natural history of the California chaparral and woodlands Natural history of the California Coast Ranges Natural history of Contra Costa County, California Endemic flora of the San Francisco Bay Area Critically endangered flora of California {{Brassicales-stub