Perennial herbs. The stems are 70-90 cm high, quadrangular, pinstriped, inverted to short bristles or become hairless, with yellowish glandular dots scattered among them, unbranched or with a few branches on the upper part.

Calyx is long 1 1- 13mm, sparsely pubescent, with small white glandular spots and extremely oblique throat. Three teeth on the upper lip are broadly lanceolate or lanceolate in the Yangtze River Delta, and two teeth on the lower lip are narrowly lanceolate, with long and pointed teeth. Corolla is purplish red or blue, 2.8-3.5 cm long, sparsely pubescent outside, slightly curved crown tube, and 65438 0.5 mm wide at the base. The narrow part protruding from the calyx is about the length of the calyx, and suddenly grows to a throat with a width of 65438 00 mm, with a crown of two lips. The middle part of the upper lip is split into two obtuse lobes, and the middle lobe of the lower lip is kidney-shaped and the middle tip is curved. Stamens shorter than lower lip or slightly protruding from posterior lip pair. Style apex nearly equal to 2-lobed, protruding beyond upper lip. Nutlets are obovate oblong, about 2.7 mm long and 65438 0.5 mm wide, with angular ventral surface, narrow base, brown and smooth. The flowering period is July -65438+ 10, and the fruiting period is August-165438+ 10.