Oxytheca parishii
Encyclopedia
Oxytheca parishii is a species of flowering plant in the buckwheat family
Polygonaceae
Polygonaceae is a family of flowering plants known informally as the "knotweed family" or "smartweed family"— "buckwheat family" in the United States. The name is based on the genus Polygonum and was first used by Antoine Laurent de Jussieu in 1789 in his book, Genera Plantarum. The name refers...

 known by the common name Parish's oxytheca. It 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 only from the Transverse Ranges
Transverse Ranges
The Transverse Ranges are a group of mountain ranges of southern California, in the Pacific Coast Ranges physiographic region that runs along the Pacific coast from Alaska to Mexico in North America. The Transverse Ranges begin at the southern end of the California Coast Ranges and lie between...

 and nearby slopes of the southernmost Central Coast Ranges. It grows in dry and rocky mountain soils. It is an annual herb producing a waxy, hairless, leafless stem up to about 60 centimeters in maximum height in the spring when it is time to flower; during the winter the plant is a small rosette of oval leaves a few centimeters wide. 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...

 atop the stem is an array of small cymes of flowers, each enveloped in a partially fused cup of bract
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...

s tipped in spinelike awns. The flower has six hairy white or pinkish lobes.

There are four varieties of this species.
  • O. p. var. abramsii (Abrams' oxytheca) is limited to the 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...

     of mountain slopes in Santa Barbara
    Santa Barbara County, California
    Santa Barbara County is a county located in the southern portion of the U.S. state of California, on the Pacific coast. As of 2010 the county had a population of 423,895. The county seat is Santa Barbara and the largest city is Santa Maria.-History:...

     and Ventura Counties
    Ventura County, California
    Ventura County is a county in the southern part of the U.S. state of California. It is located on California's Pacific coast. It is often referred to as the Gold Coast, and has a reputation of being one of the safest populated places and one of the most affluent places in the country...

  • O. p. var. cienegensis (Cienega Seca oxytheca) is known from only about six occurrences in the San Bernardino Mountains
    San Bernardino Mountains
    The San Bernardino Mountains are a short transverse mountain range north and east of San Bernardino in Southern California in the United States. The mountains run for approximately 60 miles east-west on the southern edge of the Mojave Desert in southwestern San Bernardino County, north of the...

  • O. p. var. goodmaniana (Cushenbury oxytheca) is federally listed as an endangered species
    Endangered species
    An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

    ; it is known only from loose, rocky, limestone
    Limestone
    Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

     scree
    Scree
    Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...

    on steep north-facing slopes in the San Bernardino Mountains in an area highly disturbed by limestone mining operations
  • O. p. var. parishii is found in sandy, gravelly habitat in the Transverse Ranges

External links

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