Tonestus eximius
Tahoe tonestus, Tahoe Tonestus
(c) Steve Matson, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Subshrub · Native
Conservation status: CNPS 4.3
Tonestus eximius (Tahoe tonestus) is a native California subshrub in the Asteraceae family, recognized by smaller involucre and fewer rays.
Tahoe tonestus is a native perennial ranked 4.3 by CNPS found in the Sierra Nevada Mountains, particularly in Alpine and El Dorado counties, inhabiting granite crevices and talus slopes at elevations of 1,800 to 3,300 meters. Flowering from July to August, this plant produces white ray flowers with 10 to 13 petals surrounded by disk flowers in compact clusters. Growing in dense, cespitose clumps with branched underground stems no taller than 13 centimeters, it forms a low, compact cushion-like mat. Its leaves are relatively small, reaching up to 5 centimeters long, with coarsely toothed or nearly entire margins. The distinctive involucre surrounding its flower heads is leaf-like and measures 7.5 to 16 millimeters across.
Identification and appearance
Key characters: 1 sympatric species; distinguished by smaller involucre and fewer rays
Habitat and range
Habitat: Granite crevices, talus
Elevation: 1800-3300 m
Outside California: Nevada
Bloom period
Tonestus eximius blooms Jul-Aug.
Conservation status
CNPS 4.3
How to tell it apart
vs Solidago: Tonestus is sticky-glandular; Solidago is non-sticky with smooth or slightly hairy texture.; vs Xanthisma: Tonestus foliage is sticky not spiny; Xanthisma leaves have spine-tipped teeth.; vs Pyrrocoma: Tonestus is sticky-glandular throughout; Pyrrocoma lacks stalked glands and sticky texture.; vs Petradoria: Tonestus has basal leaf rosette; Petradoria is woody shrub without basal rosette.; vs Euthamia: Tonestus is sticky with large solitary heads; Euthamia is non-sticky with small clustered heads.
Frequently asked questions
Is Tonestus eximius native to California?
Yes. Tonestus eximius is native to California (recorded as native).
When does Tonestus eximius bloom?
Tonestus eximius blooms Jul-Aug.
What plant family does Tonestus eximius belong to?
Tonestus eximius is in the Asteraceae family, genus Tonestus.
Is Tonestus eximius rare or endangered?
Tonestus eximius carries California Rare Plant Rank 4.3, state rank S3.
What habitat does Tonestus eximius grow in?
Tonestus eximius grows in Granite crevices, talus.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos · CDFW CNDDB
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.