Calanthe biloba Lindley, Fol. Orchid. 6-7(Calanthe): 3. 1855.二裂虾脊兰 er lie xia ji lan

Alismorkis biloba (Lindley) Kuntze.

Plants to 60 cm tall. Pseudobulbs cylindric, ca. 10 × 0.8 cm, 4- or 5-noded, internodes ca. 2 cm. Leaves 2 or 3, well developed at anthesis, not deciduous; blade broadly elliptic, 12-17 × 7-8 cm, papery, apex mucronate; petiole-like base sheathing, ca. 8 cm. Scape arising from leaf axil, erect, ca. 50 cm, densely puberulent, with 2 tubular sheaths below middle; rachis ca. 11 cm, laxly more than 10-flowered; floral bracts persistent, narrowly lanceolate, 10-17 mm, glabrous, apex acuminate. Flowers large, purplish with a yellowish lip; pedicel and ovary 20-25 mm, densely puberulent. Dorsal sepal broadly ovate, ca. 15 × 6-7 mm, abaxially puberulent, 5-veined, apex aristate; lateral sepals ovate, oblique, ca. 15 × 7-8 mm, abaxially densely puberulent, 5-veined, apex aristate. Petals oblong, ca. 15 × 4.5 mm, glabrous, 3-veined, apex aristate; lip adnate to base of column wings, subreniform, ca. 15 × 20 mm, clawed, deeply 2-lobed, apiculate in sinus; lobes subrhombic, margin erose, apex obtuse; disk without lamellae and other appendages; spur narrowly conic, ca. 2 mm, apex slightly obtuse. Column ca. 5 mm, thick, slightly dilated toward apex, glabrous; rostellum 2-lobed; pollinia slightly narrowly ovoid, similar in size; viscidium narrowly oblong, ca. 1 mm. Fl. Oct. 2n = 38, 48, 80.

Thickets on streamsides; ca. 1800 m. SW and W Yunnan [Bhutan, NE India, Myanmar, Nepal].