Erect herb, up to 60 cm high. Leaves ligulate, arching, unequally apically acutely bilobed, praemorse, up to 70 mm long, 15 mm wide. Inflorescence short, c. 15 mm long, single-flowered; floral bracts sheathing, ovate, 4 mm long. Flowers yellow-green, ringent; pedicel with ovary 25 – 30 mm long. Dorsal sepal narrowly ovate, apex obtuse, 28 – 32 mm long, 5 – 8.5mmwide. Lateral sepals, subfalcate, acuminate, 27 – 28 mm long, 6 – 7 mm wide. Petals linear, acuminate, 30 – 31 mm long, 3 mm wide. Labellum dark purple striped with yellow, thick, hypochile bilobed, acuminate, epichile rectangular, trilobed at apex, 20 – 21mm long, 10 – 13 mm wide. Column oblong, entire, not constricted at base, 4 mm long, 3 mm wide; rostellum triangular; anther-cap cucullate, glabrous, 3.5mm long, 3.0 mm broad; pollinia 2, hard; viscidium, < 1 mm long. Capsule not seen.
Data Deficient (DD).
Vandae cristatae Lindl. affinis sed floribus distinctis tepalis longissimis, petalis linearibus acutis et columna ad basin non constricta differt.
BURMA. Myitkyina Distr., near “Black Rock”, 1200 – 1500 m asl, 6 May 1938 Kermode 17331 (holotype K!).
Unknown; 1200 – 1500 m asl.
While Vanda longipetala is clearly related to V. cristata, it differs in the extremely long tepals, slender linear and acuminate lateral petals (length to width ratio of 10 compared with < 6 for V. cristata), and the lack of a constricted base to the column. This relationship with V. cristata is borne out in a recent morphometric study of sect. Cristatae which confirmed that V. longitepala was closely related to V. cristata (Gardiner et al. 2005). Furthermore this study, which examined all six species, recognised three morphometrically distinct species groups based on multiple characters, namely the V. longitepala/V. cristata group, the V. alpina group containing V. alpina, V. chlorosantha and V. griffithii, and the solitary V. flavobrunnea.