Description from Flora of China
Geranium affine Ledebour (1831), not Poiret (1812); G. pratense var. affine C. C. Huang & L. R. Xu; G. transbaicalicum Sergievskaja.
Perennials. Rootstock ± horizontal, 0.7-2 cm in diam., not tuberculate, with thickened roots along rootstock. Stem 23-100(-150) cm tall, erect, not rooting at nodes, with 0.1-1.7 mm retrorse to patent nonglandular trichomes and sometimes 0.2-1.2 mm patent glandular trichomes. Stipules lanceolate, distinct. Leaves opposite; petiole with 0.3-0.9 mm retrorse to patent nonglandular trichomes and sometimes 0.5-1.1 mm patent glandular trichomes; leaf blade (4.2-)6.2-11.5 cm, palmately cleft, ratio of main sinus/middle segment length = (0.81-)0.86-0.94, pilose with appressed nonglandular trichomes; segments (5 or)7(or 9), rhombic, 2.2-7.5 mm wide at base, 10-30-lobed in distal half, ratio of second sinus/middle segment length = 0.15-0.48. Cymules solitary, 2-flowered; peduncle 1.3-12 cm. Pedicel 0.3-2.5 cm, with 0.2-0.4 mm patent to retrorse nonglandular trichomes and 0.4-1.2 mm patent glandular trichomes; bracteoles lanceolate. Sepals (0.7-)1-1.2 cm, mucro (1.7-)2.2-3.9 mm, ratio of mucro/sepal length = 0.16-0.39, outside with 0.2-0.9 mm patent nonglandular trichomes and 0.3-1 mm patent glandular trichomes, inside glabrous. Petals bluish or sometimes purplish or white, (1.3-)1.5-1.9(-2.4) cm, erect to patent, both surfaces glabrous, margin basally ciliate, apex rounded. Staminal filaments pinkish, lanceolate with a broadly triangular base and an abruptly narrowed apex, both sides glabrous but proximal third with 0.2-0.6 mm cilia; anthers dark violet to bluish black, 1.8-3.1 mm. Nectaries 5, hemispheric, abaxially glabrous, apex with a tuft of trichomes. Stigma green to pinkish. Fruit 3-3.7 cm, reflexed when immature; mericarps smooth but usually with 1 or 2 transversal veins at apex, with a basal callus, with 0.3-0.7 mm ± appressed nonglandular trichomes and usually only apically with 0.2-0.9 mm patent glandular trichomes; rostrum 2.1-2.9 cm, with a 7-9 mm narrowed apex; stigmatic remains 2-3 mm. Seeds 3-3.6 mm. Fl. Jun-Jul, fr. Jul-Aug. 2n = 28.
Geranium pratense shares with species 34-36 staminal filaments with a broadly triangular base and an abruptly narrowed apex. The triangular base is as wide as long and should not be confused with slightly dilated bases of other Chinese species, which are distinctively longer than wide. Leaf blades of G. pratense are deeply divided with a deeper main and second sinus. The extreme leaf-divided forms have been segregated as G. affine or G. transbaicalicum. However, these plants can be found along the area of G. pratense intermixed with normal forms. Petal color is usually bluish but it can also be white or purplish. Petal color is not related to leaf division or other characters and seems to have little taxonomic importance. The variability of this species in the Himalayas should be studied more deeply.
Meadows, subalpine meadows; 1400-4000 m. Gansu, Nei Mongol, Qinghai, Shanxi, NW Sichuan, Xinjiang, E Xizang [Afghanistan, Kashmir, Kazakhstan, Kyrgyzstan, Mongolia, Nepal, Pakistan, Russia, Tajikistan, Turkmenistan, Uzbekistan; Europe].