Diplacus aridus
Low bush monkeyflower
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Family: Phrymaceae · Type: Shrub · Native
Conservation status: CNPS 4.3
Diplacus aridus (Low bush monkeyflower) is a native California shrub in the Phrymaceae family, recognized by shrub in granite crevices 660-1180m.
Low bush monkeyflower is a California native shrub found in the southeastern Peninsular Ranges in granite boulder crevices at elevations of 660 to 1,180 meters. Flowering from March to June, this plant produces pale yellow flowers with delicate petals in small clusters at leaf nodes. Growing 8 to 33 centimeters tall with a compact, branching form, it has small leaf clusters emerging from main leaf axils. Its leaves are uniformly green, ovate to lanceolate, with dentate or serrate edges that are often rolled under, creating a compact appearance. The fruit develops 20 to 36 millimeters long, splitting open along its upper suture.
Identification and appearance
Key characters: Geographically isolated; shrub in granite crevices 660-1180m
Habitat and range
Habitat: Crevices in granite boulders or outcrops
Elevation: 660-1180 m
Outside California: central Baja California
Bloom period
Diplacus aridus blooms Mar-Jun.
Conservation status
CNPS 4.3
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 aridus native to California?
Yes. Diplacus aridus is native to California (recorded as native).
When does Diplacus aridus bloom?
Diplacus aridus blooms Mar-Jun.
What plant family does Diplacus aridus belong to?
Diplacus aridus is in the Phrymaceae family, genus Diplacus.
Is Diplacus aridus rare or endangered?
Diplacus aridus carries California Rare Plant Rank 4.3, state rank S3.
What habitat does Diplacus aridus grow in?
Diplacus aridus grows in Crevices in granite boulders or outcrops.
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.