Diplacus thompsonii
Thompson's monkeyflower
(c) Matt Berger, some rights reserved (CC BY) · licence
Family: Phrymaceae · Type: Annual · Native
Diplacus thompsonii (Thompson's monkeyflower) is a native California annual in the Phrymaceae family, recognized by found on granitic soils in sagebrush and pine woodland.
Thompson's monkeyflower is a California native annual found in the eastern Sierra Nevada and adjacent desert mountain ranges in granitic soils, sandy slopes, and dry sagebrush flats at elevations of 1,800 to 2,600 meters. Flowering from May to July, this delicate plant produces dark magenta to red-purple flowers with a yellowish throat spotted with red, measuring 6 to 10 millimeters wide. Growing 3 to 15 centimeters tall with short glandular-soft hairs, it has a compact and delicate form. Its leaves are sessile, lanceolate to narrowly elliptic, measuring 7 to 30 millimeters long and 2 to 7 millimeters wide. The small plant features a distinctive calyx that is darkened and blackish, with glandular-soft hairs and nearly equal lobes.
Identification and appearance
Key characters: Geographically isolated; found on granitic soils in sagebrush and pine woodland
Habitat and range
Habitat: Granitic soils and sands, sandy slope, dry sagebrush flats, pinyon and Jeffrey pine woodland
Elevation: 1800-2600 m
Bloom period
Diplacus thompsonii blooms May-Jul.
How to tell it apart
vs Erythranthe: Diplacus has a corolla that withers and stays attached and typically grows in dry, rocky places; Erythranthe drops its corolla cleanly and favors wet seeps and streambanks.; vs Mimulus: Diplacus covers the shrubby and small annual western monkeyflowers with ribbed, inflating calyces; Mimulus (in the strict sense) is a fleshy-stemmed perennial with squarish 4-angled stems.; vs Mimetanthe: Diplacus is puberulent to glandular with a distinctly 2-lipped flower; Mimetanthe is densely long-soft-wavy-hairy with tiny yellow flowers and a nearly regular calyx.; vs Collinsia: Diplacus has an open funnel-throated corolla and a 5-ribbed calyx; Collinsia has a sharply 2-lipped flower with the middle lower lobe folded into a keel that hides the stamens.; vs Antirrhinum: Diplacus has an open-throated corolla and free calyx lobes; Antirrhinum (snapdragon) has a closed, pouched throat sealed by a palate and a spurless sac at the base.
Frequently asked questions
Is Diplacus thompsonii native to California?
Yes. Diplacus thompsonii is native to California (recorded as native).
When does Diplacus thompsonii bloom?
Diplacus thompsonii blooms May-Jul.
What plant family does Diplacus thompsonii belong to?
Diplacus thompsonii is in the Phrymaceae family, genus Diplacus.
What habitat does Diplacus thompsonii grow in?
Diplacus thompsonii grows in Granitic soils and sands, sandy slope, dry sagebrush flats, pinyon and Jeffrey pine woodland.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.