Impatiens forrestii Hook. fil. ex W. W. Smith

Plants annual, 35-90 cm tall. Stem erect, long naked in lower part, leafy in upper part, glabrous, simple or rarely branched and branchlets slender. Leaves alternate; petiole 1-2 cm, glabrous; leaf blade pale green abaxially, dark green adaxially, ovate-lanceolate or subelliptic, 10-15 × 3-5 cm, membranous, abaxially glabrous, adaxially adpressed strigose, lateral veins 8 or 9 pairs, curved, abaxially prominent, base broadly cuneate, margin regularly serrate, teeth glandular mucronulate, apex acuminate. Inflorescences in upper leaf axils, 2(or 3)-flowered; peduncles erect or slightly curved, ca. as long as leaves or shorter. Pedicels 1-2 cm, bracteate at base (but appearing as if at middle in upper flowers); bracts persistent, ovate-lanceolate, 3-4 mm, setose, apex glandular mucronulate. Flowers purple-red, spotted and striate, 3-3.5 cm deep. Lateral sepals 2, obliquely ovate or suborbicular, 8-9 × 5-6 mm, reticulate veined, apex mucronulate, abaxial midvein not thickened. Lower sepal saccate, ca. 3 cm deep, abruptly narrowed into an incurved spur ca. 1 cm; mouth oblique, ca. 1.8 cm wide, tip acute. Upper petal reniform, 1.8-2 × ca. 2 cm, apex cornute, abaxial midvein thickened, conspicuously carinate; lateral united petals shortly clawed, ca. 3.5 cm, 2-lobed; basal lobes suborbicular, ca. 1.4 cm in diam.; distal lobes falcate-flabellate, ca. 2 × as long as basal lobes, apex obtuse; auricle small. Filaments linear, 3-4 mm; anthers ovoid, apex acute. Ovary linear. Capsule not seen. Fl. Aug.

SW Sichuan, NW Yunnan [N Myanmar].

Shaded moist places in valleys or by streams; ca. 2600 m.