Annual or perennial herbs. Leaves entire, opposite and shortly petiolate below, alternate and usually subsessile above. Flowers in terminal bracteate racemes or rarely solitary in leaf axils. Calyx deeply and ± unequally 5-fid. Corolla tubular, bilabiate, with short, straight spur; palate not closing throat; upper lip 2-lobed, lower lip 3-lobed. Stamens 4, didynamous, included; anther cells confluent. Fruit a subglobose or obliquely ovoid capsule with unequal loculi dehiscing by 2 or 3 apical pores or apparently indehiscent. Seeds numerous, oblong-ellipsoid or cuneate-oblong; testa smooth or variously sculptured with rides, ribs or papillae.
About 20-30 species, from Spain and Morocco to India and Pakistan Represented in Pakistan by 1 (possibly 2) species. Speta (l.c. 1980) divided Chaenorhinum as traditionally accepted into two subgenera and transferred 8 species from E. Europe and S.W.Asia, including C. minus (L.) Lange, to the genus Microrrhinum (Endl.) Fourr. In his classification, the Pakistan species belongs to subgen. Tapirorrhinum Speta.
In the APG III classification (2009) Chaenorhinum is included in the expanded family Plantaginaceae.