Eulophia rutenbergiana Kraenzl., Abh. Naturwiss. Vereine Bremen 7: 255 (1882).
Homotypic Synonyms:
Graphorkis rutenbergiana (Kraenzl.) Kuntze, Revis. Gen. Pl. 2: 662 (1891).
Lissochilus kranzlinii H.Perrier, in Fl. Madag. 49(2): 13 (1941).
Pseudobulbs of the section, flat, 1-4 angled, irregular, generally 3 cm in diameter, with 3-4 linear, undulate ribs. Leaves falling, slightly prior to flowering, graminiform, narrow and long. Inflorescence 40-60 cm tall, ordinarily equal to the leaves, peduncle 25-60 cm, 10-12 times longer than the cluster; duster dense, elliptical, half as long as wide (3-6 x 3-4 cm); bracts thin, reddish, narrowly linear-lanceolate, filiform, longer than the pedicel; flowers average (2 cm long), sulpher yellow with the labellum yellow with brown stripes, and the lateral lobes yellow-brown. Sepals oblong, 2 cm long, median acute and 9 veined laterals larger and enlarged anteriorly, basally. Petals similar to the median sepal but smaller and apiculate. Labellum (20 x 9 mm), enlarged medially and attenuate to the base, notched at the point of division of the lobes, laterals marginal and vertical, the median obovate-oblong apically and deeply notched, obtuse; provided basally with 2 short, villous crests and several humps; spur abort (3 mm), straight and Obtuse. Column 5 mm tall, with the rear margins of the clinandrium enlarged in a deltoid-obtuse point, 1 mm tall. Anther provided behind with a small, short, thick hump in front of the short, obtuse median tongue.
In secondary grasslands and on rocky slopes at elevations of 500 to 2000 meter .
Flowering in January-March.
As given for the genus, warm to cool growing terrestrial.
Flora of Madagascar: vascular plants: 49th family, Orchids / by H. Perrier de La Bathie; published under the auspices of the government of Madagascar and under the direction of H. Humbert; English revision and translation by Steven D. Beckman; Field Guide to the Orchids of Madagascar Cribb & Hermans 2009; Orchids of Madagascar Hermans, Du Puy, Cribb & Bosser
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Habitat/In situ 
eulophia rutenberbiana 
Photograph ©Gilles
Grunenwald. Image used
with kind permission.