23. Allostigma W. T. Wang, Acta Phytotax. Sin. 22: 185. 1984.
异片苣苔属 yi pian ju tai shu
Herbs, perennial, terrestrial, rhizomatous. Stems simple. Leaves few, along stem, opposite, equal to subequal in a pair; leaf blade puberulent, base cuneate to cordate. Inflorescences lax, axillary, 3-5-flowered cymes; bracts 2, opposite. Calyx actinomorphic, 5-lobed; segments equal. Corolla zygomorphic, inside glabrous; tube funnelform-tubular, not swollen, longer than limb, 8-10 mm in diam.; limb 2-lipped; adaxial lip 2-lobed, much shorter than abaxial lip; abaxial lip 3-lobed, lobes subequal, apex rounded. Stamens 2, adnate to abaxial side of corolla tube near middle, included; anthers basifixed, coherent at apex, thecae parallel, not confluent at apex, dehiscing longitudinally; connective prominent; staminodes 3, adnate to adaxial side of corolla tube. Disc ringlike. Ovary linear, 2-loculed; placenta 1, axile. Stigmas 2, unequal, smaller 1 triangular, undivided, larger 1 narrowly obtrapeziform, emarginate. Capsule straight in relation to pedicel, linear, much longer than calyx, dehiscing loculicidally to base; valves 2, straight, not twisted. Seeds unappendaged.
* One species: endemic to China.
Allostigma is very similar to Pseudochirita except that it has axile placentation while Pseudochirita has parietal placentation.
