Narrow evening primrose
Calylophus serrulatus is a(n) perennial subshrub, which grows 5 cm to 40 cm in height. This species is commonly found from low to high elvevations throughout the Hills area; mixed grass prairie (especially barren or eroded areas), open pine forests, dry rocky slopes, and limestone outcrops. The leaves are lenear to linear-lanceolate or narrowly oblanceolate, shallowly toothed, and often folded along the midrib. Calylophus serrulatus has yellow flowers that bloom from June to August.