Species Information - Dendrobium aurantitepalum

Dendrobium aurantitepalum de Vogel in De Vogel, E.F., van Vugt, R. & Hoogendijk, E.A.H., Dendrobium section Diplocaulobium subsection Goniobulbon (Orchidaceae) 1: The Species with 4 or 5 Keels on the Epichile, Malesian Orchid Journal Vol. 22 (2018): 84, fig. 1-3

Type: Leiden cult. 20110797 (de Vogel) (holo L)

Synonyms:

Roots filiform, flexuose, thin, 0.1–0.15 cm thick. Rhizome creeping. Pseudobulbs c. 0.5 cm apart, partly overlapping and appressed to the base of the next pseudobulb, conspicuously dorso-ventrally flattened, elliptic in outline, 1–1.4 by 0.8–0.9 by c. 0.3 cm; with a low median ridge; often long covered by a dried, membranous scale leaf. Leaves ovate to elliptic, 1.5–3 by 1.1–1.2 cm, index 1.9–2.5; apex more or less oblique, notched, with acute lobules; rather thin coriaceous. Inflorescences 1 per pseudobulb, arising in succession from the pseudobulb, 1.7–2.3 cm long; peduncle 0.2–0.25 cm long, much shorter than the 0.4–0.7 cm long spathe. Flower 1.4–1.6 cm high, widely open. Pedicel and ovary 0.8–1 cm long, terete, not grooved. Median sepal narrowly triangular, 0.9–1.1 by c. 0.4 cm; recurved; flat to slightly concave; apex acute. Lateral sepals falcate, obliquely triangular, 0.9–1.2 by c. 0.75 cm; top half semi-tubular; apex acute; mentum conical, obtuse, c. 0.6 cm long. Petals lineartriangular, 0.8–1.05 by 0.12–0.2 cm; somewhat semitubular except at the base; apex acute. Lip gently curved in the middle; keels 5, minutely papillose (magn. 25×); hypochile when flattened c. obovate to rectangular, widest in front when flattened, c. 0.7 by 0.4–0.5 cm, narrower at the base and there broadly attached over the entire width leaving no auricles; lateral lobes in lateral view in front broadly rounded, receding; keels 2, rather wide apart, parallel and straight or curved, distinctly swollen; in top 1/4 of the hypochile converging and almost touching; epichile when flattened broadly ovate or elliptic, c. 0.45–0.6 by 0.3–0.55 cm; top rounded with acute tip to acute, with more or less coarsely irregular margin; median keel from base to well below the top of the epichile, somewhat undulating; inner lateral keels plate-like and undulating with 4–7 curves, about as long as the median keel; outer lateral keels short, low, less than 1/4 of the length of the epichile. Column c. 0.2 by 0.25–0.3 cm, c. 0.3 cm wide; clinandrium 3-lobulate, the lateral lobules broadly triangular, the median one subulate; column-foot gently curved, in natural position c. 0.7 cm long. Anther in outline bell-shaped, c. 0.15 by 0.12–0.15 cm; apex truncate or retuse, sometimes notched.
(After De Vogel in De Vogel, Vugt & Hoogendijk 2018)

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