Perennials. Rootstock ± vertical, 4-8 mm in diam., not tuberculate, with a fascicle of long and thickened roots. Stem 23-48(-72) cm tall, erect, not rooting at nodes, with 0.3-1 mm retrorse appressed nonglandular trichomes. Stipules lanceolate, connate at least at base. Leaves opposite; petiole with 0.2-1 mm retrorse appressed nonglandular trichomes; leaf blade 3.7-5.9 cm, palmately cleft, ratio of main sinus/middle segment length = (0.83-)0.86-0.95, pilose with appressed nonglandular trichomes; segments 5, rhombic, 1.6-5.7 mm wide at base, 4-7(-10)-lobed in distal half, ratio of second sinus/middle segment length = 0.23-0.46. Cymules solitary, 2-flowered; peduncle 2.2-6.4(-10) cm. Pedicel 1.8-4.4 cm, with 0.2-0.5 mm retrorse appressed nonglandular trichomes; bracteoles lanceolate. Sepals 5.5-6.9(-9) mm, mucro 0.9-1.5(-2) mm, ratio of mucro/sepal length = 0.13-0.28, outside with 0.3-1.6 mm antrorse ± appressed nonglandular trichomes, inside glabrous. Petals light pink, (0.8-)0.9-1.3(-1.4) cm, erect to patent, outside basally with trichomes, inside basal 1/3-1/2 or rarely to apex with trichomes, margin basally ciliate, apex rounded. Staminal filaments pinkish, lanceolate with an abruptly narrowed apex, abaxially pilose and proximal half ciliate, trichomes 0.2-0.8 mm; anthers bluish, 1.4-2 mm. Nectaries 5, hemispheric, usually glabrous. Stigma reddish. Fruit 1.7-2.6 cm, erect when immature; mericarps smooth, with a basal callus, with 0.2-0.7 mm ± patent nonglandular trichomes and apically with 0.9-1.2 mm patent glandular trichomes; rostrum 1-1.8 cm, with a 1.5-2.1 mm narrowed apex; stigmatic remains 2.8-4.5 mm. Seeds 1.6-2 mm. Fl. Jul-Aug, fr. Aug-Sep. 2n = 28.