Cacaliopsis is a monotypic genus of flowering plants in the aster family, Asteraceae, comprising a single species: Cacaliopsis nardosmia, commonly known as silvercrown. The genus was previously placed within the broader genus Cacalia before being segregated on morphological and phylogenetic grounds. It is native to western North America.
The plant is a perennial herb that grows from rhizomes supported by a fibrous root system. Its erect stem can reach approximately 90 centimetres in height. The leaves are arranged alternately and are concentrated near the base of the stem; their blades are deeply lobed and subdivided into toothed segments, reaching up to 35 cm in length on petioles of comparable size. Both surfaces of the blades are hairy, with the undersides particularly woolly.
Flowering occurs from May through July. The flower heads are borne in arrays or clusters, each head 1.5–2 cm long and subtended by bracts of similar length. Each head contains up to 50 disc florets in yellow or orange; ray florets are absent, giving the inflorescence a compact, brush-like appearance characteristic of the tribe Senecioneae. The fruit is a ribbed, cylindrical cypsela topped by a pappus of numerous white, barbed bristles that aid wind dispersal.
Distribution
Cacaliopsis nardosmia ranges from southern British Columbia south to northern California, occurring along both the Cascade Range and the northern Coast Ranges. It grows in oak and pine forests and open meadows, and is notably tolerant of serpentine soils.
Taxonomy Notes
Cacaliopsis was formerly treated as part of the broadly circumscribed genus Cacalia, with its sole species known as Cacalia nardosmia. The genus was erected to accommodate a morphologically distinct western North American lineage within the tribe Senecioneae (Asteraceae). GBIF recognises Cacaliopsis as an accepted genus with one descendant taxon.
