Clarkia biloba
Encyclopedia
Clarkia biloba is a species of flowering plant in the evening primrose family
known by the common name Twolobe clarkia.
Clarkia biloba is endemic to California
, where it is known from the Sierra Nevada foothills; one subspecies can also be found in the San Francisco Bay Area
. It grows in chaparral
and woodland habitat.
. The top of the erect stem is occupied by the inflorescence
, which bears hanging buds above open flowers. The pink or red-purple sepal
s remain fused as the petals spread and emerge from one side of the bud. The petals are up to 2.5 centimeters long and pink to lavender to magenta, sometimes flecked with red. Each petal has a two-lobed tip. There are 8 stamen
s, some with large lavender anthers and some with smaller, paler anthers. The stigma
protrudes past the stamens.
There are three subspecies of this wildflower. The rarest, the Mariposa clarkia (ssp. australis), is known only from the Merced River
drainage, in the Sierra foothills, where it is threatened by road maintenance and non-native plants
.
Onagraceae
Onagraceae, also known as the Willowherb family or Evening Primrose family, are a family of flowering plants. The family includes about 640-650 species of herbs, shrubs, and trees in 20-24 genera...
known by the common name Twolobe clarkia.
Clarkia biloba is endemic to 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...
, where it is known from the Sierra Nevada foothills; one subspecies can also be found in the San Francisco Bay Area
San Francisco Bay Area
The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...
. It grows in chaparral
Chaparral
Chaparral is a shrubland or heathland plant community found primarily in the U.S. state of California and in the northern portion of the Baja California peninsula, Mexico...
and woodland habitat.
Description
Clarkia biloba is an annual herb producing an erect stem approaching a meter in maximum height. The leaves are linear to lance-shaped and up to 6 centimeters long. Each is borne on a short petiolePetiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
. The top of the erect stem is occupied by the inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
, which bears hanging buds above open flowers. The pink or red-purple sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s remain fused as the petals spread and emerge from one side of the bud. The petals are up to 2.5 centimeters long and pink to lavender to magenta, sometimes flecked with red. Each petal has a two-lobed tip. There are 8 stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s, some with large lavender anthers and some with smaller, paler anthers. The stigma
Gynoecium
Gynoecium is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves which evolved to form a closed structure containing the ovules...
protrudes past the stamens.
There are three subspecies of this wildflower. The rarest, the Mariposa clarkia (ssp. australis), is known only from the Merced River
Merced River
The Merced River , in the central part of the U.S. state of California, is a -long tributary of the San Joaquin River flowing from the Sierra Nevada into the Central Valley. It is most well known for its swift and steep course through the southern part of Yosemite National Park, and the...
drainage, in the Sierra foothills, where it is threatened by road maintenance and non-native plants
Introduced species
An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...
.