Species Information - Dendrobium novobritannicum

Dendrobium novobritannicum de Vogel in De Vogel, E.F., van Vugt, R. & Hoogenfdijk, 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): 104, fig. 24-27

Type: Leiden cult. 20080720 (de Vogel & Raka) (holo L)

Synonyms:

Roots filiform, flexuose, to 0.1 cm thick; glabrous, white, tip pale greenish. Rhizome short, creeping; rhizome scales c. as long as the pseudobulbs, soon dry and papyraceous, slowly decaying, long persistent around the pseudobulbs. Pseudobulbs close together, ascending, ovate-oblong, 1.5–2.5 by 0.7–1 cm; distinctly tapering to the top; slightly flattened, 6-ribbed, the ribs on the flatter side closer together. Leaves ovate-oblong, 3.2–5 by 0.9–1.4 cm, index c. 3.5; base narrowed; apex with acute to rounded lobules. Inflorescences 1(–2) per pseudobulb, developing in succession, 4-5 cm long; peduncle 0.6-1.1 cm long, shorter or longer than the spathe; spathe 0.8-0.9 cm long. Pedicel and ovary c. 3-3.4 cm long; pedicel terete, white; ovary with 3 inconspicuous ribs. Flower c. 3 cm across. Median sepal narrowly triangular, c. 1.35 by 0.35 cm; top half semi-tubular; apex acute; 5-nerved. Lateral sepals obliquely narrowly triangular, widest at the base, 1.35 by c. 0.6 cm; top half semi-tubular; apex acute; mentum conical, obtuse, c. 0.5 cm long; 5-nerved. Petals narrowly linear, c. 1.2 by 0.1 cm; top half semi-tubular ; apex acute; at the base 3-nerved. Lip oblong-ligulate, constricted in about the middle, when flattened c. 1.2 cm long; 5-nerved and 5-keeled, rarely the outer lateral keels only partly developed. Hypochile when flattened in outline obovate, c. 0.6 by 0.33 cm; lateral lobes in front projecting for c. 0.05 cm, triangular; keels 2, wide apart, parallel, rather thick, in top 1/4 of the hypochile conniving, continuing as lower, thin, plate-like, much undulating keels (5–6 curves) up c. halfway the epichile; epichile ovate-oblong, c. 0.75 by 0.27 cm; top narrowly triangular, with apiculate tip, this tip below keeled; median with undulating third keel almost up to 1/3 of the top. Column in lateral view oblique triangular, 0.122 by 0.2 cm, c. 2 cm wide; clinandrium 3-lobulate, the lateral lobules broadly triangular, the median lobule rather narrowly triangular, c. 0.5 cm long; column-gently curved, in natural position c. 0.5 cm long Anther semi-elliptic -cucullate, c. 0.1 by 0.1 cm; apex truncate.
(After De Vogel in De Vogel, Vugt & Hoogendijk 2018)

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