Description from Flora of China
Herbs biennial or perennial, rarely subshrubs, scabrous. Leaves petiolate or sessile, margin entire. Cymes scorpioid, solitary at stem apex or terminating stems and branches and forming a panicle, usually elongated in fruit, bracteate. Flowers actinomorphic, pedicellate or sessile. Calyx parted to or nearly to base; lobes 5, linear or linear-lanceolate, equal, usually enlarged after anthesis. Corolla blue, yellow, rarely white or red, tubular-campanulate or retrorse-conical, usually gradually expanded from base upward, rarely abruptly expanded from middle; throat unappendaged; nectary ringlike or irregularly lobed, pubescent or glabrous; lobes vertical or recurved, margin dentate. Anthers laterally coherent into a tube or sagittate at base, usually pellucid, emarginate, apex sterile. Style included or slightly exserted; stigma capitate. Gynobase flat. Nutlets 4, erect, ovate-triangular, length and width subequal, adaxially usually ribbed, abaxially slightly convex; attachment scar basal.
About 145 species: centered in Asia, 29 species in China.