Description from Flora of China
Alpinia koshunensis Hayata; Languas formosana (K. Schumann) Sasaki; L. koshunensis (Hayata) Sasaki.
Pseudostems to 1(--3.5) m. Ligule to 1 cm, abaxially villous, apex obtuse; petiole absent to 1 cm; leaf blade lanceolate or oblong-lanceolate, 50--70 × 8--12 cm, both ends acuminate. Panicles narrow, 15--20 cm; rachis glabrous or sparsely villous; branches 2- or 3-flowered; bracteoles elliptic, ca. 1.5 cm, apex mucronate. Pedicel ca. 3 mm. Calyx 1.3--1.7 cm, split on 1 side, apex 3-toothed, ciliate. Corolla tube ca. 1 cm, glabrous; lobes oblong, ca. 1.5 cm, apex ciliate. Lateral staminodes subulate, less than 2 mm. Labellum white tinged with yellow, marked with red stripes at center, broadly ovate, ca. 3 cm, apex shortly 2-cleft, crisped. Stamen ca. 2 cm, with a kneelike bend. Ovary subglobose, white sericeous. Capsule vermilion, ellipsoid, wrinkled. Fl. Jul--Aug.
This species was recognized as a natural hybrid between Alpinia intermedia and A. zerumbet by Yang and Wang (in Chiu & Peng, Proc. Cross-Strait Symp. Florist. Diversity Conservation, 183--197. 1998).