Lyon's Pentachaeta

Pentachaeta lyonii

Lyon’s pentachaeta is a California endangered plant species, which means that killing or possessing this plant is prohibited by the California Endangered Species Act (CESA). The species is also listed as endangered under the federal Link opens in new windowEndangered Species Act. Lyon’s pentachaeta is an annual plant in the sunflower family (Asteraceae) that blooms with yellow flower heads from March through August. During a prolific year, each plant can produce up to 1,000 seeds, which are able to persist in the soil during dry years.

Lyon’s pentachaeta tends to occur in grassland vegetation communities on rocky clay soils of volcanic origin. These grassland habitats are often patches within a fire-adapted mosaic of chaparral and coastal sage scrub. The species only occurs in the Santa Monica Mountains; however, historical populations are reported from Santa Catalina Island and the Palos Verdes Peninsula. Some populations are protected on local agency and federal land but the majority of populations are on private land. Habitat loss due to urban development is currently the primary threat to the species. Urban development has increased the spread of invasive plants and has altered ecosystem processes such as fire, pollinator presence, and gene flow. Lyon’s pentachaeta has a limited range and populations may be vulnerable to effects from random events such as drought. Future efforts to protect and manage Lyon’s pentachaeta on private lands will require cooperation with landowners and land managers.

A study of the Link opens in new windowEcology and Distribution of Braunton’s milkvetch (Astragalus brauntii) and Lyon’s pentachaeta (Pentachaeta lyonii) was conducted with the support from the Link opens in new windowCooperative Endangered Species Conservation Fund.

CDFW may issue permits for Lyon’s pentachaeta pursuant to CESA, and you can learn more about California laws protecting Lyon’s pentachaeta and other California native plants. Populations of Lyon’s pentachaeta occur in CDFW’s South Coast Region. More information is also available from the Link opens in new windowU.S. Fish and Wildlife Service Species Profile for Lyon's pentachaeta.

Updated 10/16/2018

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yellow, daisy-like flower
Pentachaeta lyonii photo © link opens in new windowMichael Charters

black and white line drawing
Pentachaeta lyonii, CDFW illustration by Mary Ann Showers. Click to enlarge.