''Streptanthus vernalis'' 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 l ...

known by the common name early jewelflower. It was first observed in the 1970s but not actually described to science until 2005.O'Donnell, R. and R. W. Dolan. (2005)
A new species of ''Streptanthus'' (Brassicaceae) from Three Peaks in Lake County, California.
''Madroño'' 52(3) 202-6. 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 ...

Lake County, California Lake County is a county located in the north central portion of the U.S. state of California. As of the 2020 census, the population was 68,163. The county seat is Lakeport. The county takes its name from Clear Lake, the dominant geographic f ...

, where it is known from a single occurrence at Three Peaks near the

Napa County Napa County () is a county north of San Pablo Bay located in the northern portion of the U.S. state of California. As of the 2020 census, the population was 138,019. The county seat is the City of Napa. Napa County was one of the original c ...

line. It is apparently limited to serpentine outcrops in forested 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 Mediterrane ...

habitat.

Genetic analysis Genetic analysis is the overall process of studying and researching in fields of science that involve genetics and molecular biology. There are a number of applications that are developed from this research, and these are also considered parts of ...

indicates that the species is distinct from other ''Streptanthus'' and is most closely related to ''

Streptanthus morrisonii ''Streptanthus morrisonii'' is an uncommon species of flowering plant in the mustard family known by the common name Morrison's jewelflower. It is endemic to California, where it is known from the North and Central Coast Ranges. It is limited to ...

'', which it resembles. It is a hairless annual herb producing an erect branching or unbranched stem 2 to 20 centimeters tall. The ephemeral basal leaves have thick, fleshy leaves which are green and unmottled on top and purple on the undersides. Leaves higher on the stem are linear to lance-shaped and lack petioles. Flowers occur at intervals along the upper stem. Each flower has an urn-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 ...

s which is solid green with no purple or yellowish tinge. The petals emerging from the tip are white without darker veining. The fruit is a flattened straight

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 ...

3 to 5 centimeters long containing orange seeds.

References

External links

Jepson Manual TreatmentCalifornia Native Plant Society Rare Plant ProfileThe Nature ConservancyPhoto gallery
vernalis Endemic flora of California Natural history of Lake County, California Plants described in 2005 {{Brassicales-stub