Description from Flora of China
Echinospermum Sweet ex Lehmann.
Plants annual or biennial, rarely perennial, pilose, strigose, rarely sericeous throughout, hairs tuberclelike or discoid at base. Leaves alternate. Inflorescence a drepanium, elongated after anthesis, bracteate. Calyx 5-parted nearly to base; lobes frequently enlarged in fruit. Corolla light blue, rarely white, campanulate or low salverform; tube short; throat appendages 5, trapeziform; limb 5-parted. Stamens included. Ovary globose, 4-parted. Style not exserted; stigma capitate. Gynobase subulate veined, ca. as long as or surpassing nutlets, rarely shorter. Nutlets 4, adherent to gynobase by entire adaxial rib or only by rib base, erect, homomorphic or heteromorphic; margin of abaxial surface usually with 1(-3) rows of glochids; bases of glochids separated or contiguous or confluent into a wing, rarely reduced to tubercles.
About 61 species: temperate regions of Africa, Asia, Europe, and North America; 36 species in China.