Species Information - Dendrobium parvibulbum

Dendrobium parvibulbum 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): 107, fig. 28

Type: Leiden cult. 20032406 (de Vogel et al.) (holo L)

Synonyms:

Roots filiform, flexuose, 0.08–0.15 cm thick; glabrous. Rhizome rather short, creeping; rhizome scales soon partly decaying, remains more or less long persistent around the pseudobulbs. Pseudobulbs, touching, close together, rather oblique on the pseudobulb, not curved, ovate, to 1.5 by 0.5 cm; more or less tapering to the top; 4-angular. Leaves lanceolate, 1.5–2 by c. 0.8 cm, index c. 1.5; base narrowed; apex equally obtusely triangular-2- dentate. Inflorescences 1 per pseudobulb, developing in succession, c. 4 cm long; peduncle c. 0.8 cm long, shorter or longer than the spathe; spathe triangular, 0.6–1 cm long. Pedicel 2.4–3 cm long; ovary slender obconical, 0.15 cm long, with flat jugae. Flower 2.3–2.6 cm across, with strongly recurved sepals and petals; Median sepal narrowly triangular, c. 2.35 by 0.4 cm; in top half concave to semi-tubular, slightly thickened; apex acute, tip rounded; 5-nerved. Lateral sepals strongly falcate, obliquely triangular, widest at the base, c. 2.1 by c. 0.85 cm; in top half concave to semi-tubular, slightly thickened; apex acute, tip rounded; 5-nerved; mentum broadly conical, obtuse, 0.7 cm long. Petals linear, c. 2.1 by 0.23 cm; in top half concave to semi-tubular, slightly thickened; from a narrower base slightly widened near the base; apex acute, tip rounded; 3-nerved. Lip rather narrowly attached to the column-foot, oblong-ligulate, when flattened constricted below the middle, 1.5 cm long; 5-keeled, keels very minutely papillose (50x); hypochile when flattened in outline elliptic, 0.6 by 0.6 cm; lateral lobes in front not developed, at the back with a small rounded auricle; keels 2, starting slightly above the base of the lip, wide apart, c. parallel, rather thick, in top 1/4 of the hypochile converging; epichile ovate, 0.7–0.75 by c. 0.5 cm; top triangular, below keeled, with acute tip; inner lateral keels continuing as lower, thin, plate-like, much undulating keels (c. 7 curves) to c. 0.2–0.25 cm from the top of the epichile; median with a much less undulating low keel from the base of the epichile to c. 0.2–0.4 cm from the top of the epichile; outer lateral keels inconspicuous, much shorter and lower, irregularly incised keel. Column in lateral view oblique triangular, c. 0.2 by 0.25–0.3 cm, c. 0.2–0.25 cm wide; clinandrium 3-lobulate, the lateral lobules broadly triangular with an apiculate tip, the median lobule rather narrowly triangular, c. 0.08 cm long; column-foot distinctly curved at c. 1/3 of its base, in natural position c. 0.65 cm long. Anther trapezium- to bell-shaped in outline, c. 0.1 5 by 0.12–0.15 cm; apex truncate.
(After De Vogel in De Vogel, Vugt & Hoogendijk 2018)

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