Sairocarpus D.A. Sutton, A revision of the tribe Antirrhineae (1988).
Annual or perennial herbs; stems homomorphic, erect or ascending, often with flexuous or cirrhous lateral branches in inflorescence. Leaves usually homomorphic, simple, entire, petiolate or sessile, pinnately veined, the rnidrib terminating in a small gland, opposite below, alternate above; petiole not cirrhous. Flowers zygomorphic, pedicellate, solitary in leaf-axils or in terminal, bracteate or leafy racemes or panicles. Bracts leaf-like at least below, often subtending additional cirrhous branch or rarely 2 branches, the lowermost bracteoles of branches broad, opposite, the upper narrower, alternate. Pedicel usually not cirrhous, straight or somewhat sinuate in fruit, very rarely twining. Calyx deeply divided; the lobes subequal or unequal, entire, valvate or rarely imbricate, usually shorter than, rarely exceeding corolla-tube; adaxial lobe exceeding lateral lobes. Corolla with tube cylindrical, usually gibbous or saccate at base; limb unequally 2-lipped, the adaxial lip reflexed or patent, rarely erecto-patent, the abaxial lip usually spreading, exceeding adaxial; lobes entire, the middle lobe of abaxial lip exceeding lateral lobes; palate prominent, partially or more or less entirely occluding mouth of tube. Fertile stamens 4, didynamous, included; connective not dilated above anthers; adjacent pairs of anthers marginally coherent; thecae initially reflexed; staminode minute, entire, without rudimentary anther. Style simple, the base obliquely inserted; stigma included, clavate, entire, positioned between pairs of fertile stamens. Capsule ovoid to oblong, the walls somewhat papery, the septum erect, more or less straight; the loculi equal or subequal in length, subequal or unequal in breadth, many-seeded; adaxial loculus dehiscing from apex initially at 1 or rarely 2 points forming single, irregularly-toothed pore, simultaneously with or somewhat after abaxial loculus; abaxial loculus initially dehiscing at 2 points, forming 2 or 1 irregularly-toothed pores, if 2 pores then occasionally becoming fused to form single pore. Seeds ovoid, oblong-ellipsoid or conical, dorsi-ventrally asymmetrical, cristate, tuberculate or reticulate-alveolate, ridges and tubercles of dorsal face smaller than those of ventral face; hilum on dorsal face, subbasal to 0.3 distance from base to apex.
By Sutton (1988)