13. Paphiopedilum charlesworthii (Rolfe) Pfitzer, Bot. Jahrb. Syst. 19: 40. 1894.
红旗兜兰 hong qi dou lan
Cypripedium charlesworthii Rolfe, Orchid Rev. 1: 303. 1893; Cordula charlesworthii (Rolfe) Rolfe.
Plants terrestrial. Leaves 4 or 5, distichous; blade abaxially pale green and with blackish purple spots near base, adaxially uniformly green or sometimes very obscurely tessellated with dark and light green, linear-oblong, 14-16 × 1.5-2 cm, apex acute and unequally bilobulate. Scape erect, terminating in a solitary flower; peduncle 8-12 cm, green, mottled with purple-brown, shortly pubescent; floral bract green spotted or mottled with deep purple, subelliptic-obovate, conduplicate, 2.1-2.8 × 1.4-1.8 cm, minutely ciliate; pedicel and ovary 2.9-3.4 cm, densely pubescent, 3-ribbed. Flower 6-8 cm in diam.; dorsal sepal pink or pinkish white, with darker veins; synsepal greenish, veined with brownish; petals pale green-yellow, with dense brown reticulate venation; lip pale yellow-brown, with darker veins; staminode white. Dorsal sepal erect, suborbicular to transversely elliptic, 3.9-4.6 × 4.5-6.7 cm, abaxially minutely puberulent particularly on midvein, adaxially purple hairy toward base, minutely ciliate, subtruncate or slightly mucronate at apex; synsepal elliptic-ovate, 3-3.5 × 1.6-2.3 cm, abaxially puberulent, minutely ciliate. Petals oblong-spatulate, 3.8-4.4 × 0.9-1.4 cm, adaxially purple villous toward base, ciliate, slightly undulate at margin; lip helmet-shaped, 3.4-4 cm; pouch 2.2-2.5 × 2-2.4 cm, with a very wide mouth. Staminode obovate, 9-10 × 8-9 mm, with a central umbo. Fl. Sep-Oct.
Rocky and humus-rich places in evergreen broad-leaved forests; 1300-1600 m. W Yunnan (W-facing slope of Gaoligong Shan) [Myanmar, Thailand].