''Tonestus peirsonii'' is a local-endemic species of flowering plant in the family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...

known by the common names Inyo tonestus, Peirson's serpentweed and Peirson's tonestus.

Distribution

The plant 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 ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, where it is known only from the Eastern High Sierra Nevada, and the White Mountains across

Owens Valley Owens Valley (Numic Numic is a branch of the Uto-Aztecan language family. It includes seven languages spoken by Native American peoples traditionally living in the Great Basin, Colorado River basin, Snake River basin, and southern Great Pl ...

to the east, both within

Inyo National Forest Inyo National Forest is a United States National Forest covering parts of the eastern Sierra Nevada of California and the White Mountains of California and Nevada. The forest hosts several superlatives, including Mount Whitney, the highest poi ...

. It grows in mountain habitat in

subalpine Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial f ...

and

alpine climate Alpine climate is the typical weather (climate) for elevations above the tree line, where trees fail to grow due to cold. This climate is also referred to as a mountain climate or highland climate. Definition There are multiple definitions of ...

s at 2900–3700 m, preferring rock talus or niches in granite cliffs. These images are from the original type location high in Rock Creek basin, Inyo County CA.

Description

''Toiyabea peirsonii'' is a perennial herb producing a branching stem from a

caudex A caudex (plural: caudices) of a plant is a stem, but the term is also used to mean a rootstock and particularly a basal stem structure from which new growth arises.pages 456 and 695 In the strict sense of the term, meaning a stem, "caudex" is m ...

and

taproot A taproot is a large, central, and dominant root from which other roots sprout laterally. Typically a taproot is somewhat straight and very thick, is tapering in shape, and grows directly downward. In some plants, such as the carrot, the taproo ...

unit, reaching up to about 20 centimeters tall and taking a clumpy form. The leaves are up to 8 centimeters long, variable in shape but usually broader toward the end, and with toothed edges. Dried remnants of leaves or flowers from previous years may be visible. The

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. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is usually a single

flower head A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, compos ...

, or a cluster of up to four heads, each up to 2 centimeters wide with green, rough-haired

phyllaries In botanical terminology, a phyllary, also known an involucral bract or tegule, is a single bract of the involucre of a composite flower. The involucre is the grouping of bracts together. Phyllaries are reduced leaf-like structures that form one or ...

in a broad (14-28mm) somewhat leaf-like

involucre 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 usually different from foliage leaves. They may be smaller, larger, or of ...

below the flower. The head bears 16-20 curling, bright yellow ray florets around a center containing many tubular disc florets. Blooming occurs in July and August.

References

External links

Jepson Manual Treatment of ''Tonestus peirsonii''''Tonestus peirsonii'' Photo galleryFlora of North America
Astereae Endemic flora of California Flora of the Sierra Nevada (United States)

• In typography, a bullet or bullet point, , is a typographical symbol or glyph used to introduce items in a list. For example: *Point 1 *Point 2 *Point 3 The bullet symbol may take any of a variety of shapes, such as circular, square, diamo ...

Natural history of Inyo County, California Flora without expected TNC conservation status {{Astereae-stub