Page author: David Giblin
Triodanis perfoliata
clasping-leaf Venus'-looking-glass

Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across most of North America to the Atlantic Coast.

Habitat: Various habitats, from the valleys and plains to moderate elevations in the moutains.

Flowers: May-August

Origin: Native

Growth Duration: Annual

Conservation Status: Not of concern


Erect annual herbs, the stems erect, usually simple, 1-6 dm. tall, the surface rough.


Leaves alternate, sessile, cordate-clasping, rotund-ovate, palmately veined, the leaves 0.5-3 cm. long and wide, or the lowermost ones narrower, more obovate, and short-petiolate.


Flowers sessile in the axils of the middle and upper leaves, 1-several in each axil, in a leafy, spike-like arrangement; calyx lobes 5, divided to the base, narrowly triangular and pointed, 5-8 mm. long; corolla united, regular, the 5 lobes longer than the tube, 8-13 mm, long, deep purple to pale lavender; stamens 5, free from the corolla and from each other; the lower flowers do not open and the calyx of these is smaller and 3- or 4-lobed; ovary inferior.


Capsules oblong, 2- or 3-celled, about 1 cm. long in the open flowers, half that size in the others.

Accepted Name:
Triodanis perfoliata (L.) Nieuwl.
Publication: Amer. Midl. Naturalist 3(7): 192. 1914.

Synonyms & Misapplications:
Legousia perfoliata (L.) Britton
Specularia perfoliata (L.) A. DC.
Additional Resources:

PNW Herbaria: Specimen records of Triodanis perfoliata in the Consortium of Pacific Northwest Herbaria database

WA Flora Checklist: Triodanis perfoliata checklist entry

OregonFlora: Triodanis perfoliata information

E-Flora BC: Triodanis perfoliata atlas page

CalPhotos: Triodanis perfoliata photos

33 photographs:
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