Species Information - Dilochia wallichii

Dilochia wallichii Lindl., Gen. Sp. Orchid. Pl. (1830) 38

Type: Wallich 1952 (Singapore) (holo K-WALL)

Synonyms:

• Arundina wallichii (Lindl.) Rchb.f., Xenia Orchid. 2 (1862) 13, t. 105, II, 13-15
• Dilochia pentandra Rchb.f., Bonplandia 5 (1857) 54
  - Type: not designated
• Arundina pentandra (Rchb.f.) Rchb.f., Xenia Orchid. 2 (1862) 11, t. 105, I, 1-12

Plant up to 100 cm long. Roots much branched, 0.3-0.4 cm diam., hairy. Rhizome c. 0.6 cm diam. Leaf sheath longitudinally ribbed but highest ones sometimes not, free part 2.5-5 cm long; lower ones widened at the top, without leaf blade, higher ones widened from halfway upwards. Leaf blade narrowly ovate, 3.6 -17 by 1.2-4.8 cm; petiole-like base 0.3-1 cm long; apex cuspidate. Raceme with 0-2 branches, 7-8-flowered, 8.2-20 cm long; branches 4-8 flowered. Peduncle consisting of 2-4 internodes, 1-5.7 cm long, enclosed by 2-4 sterile bracts. Rachis 5.2-19 cm long, 0.1-0.4 cm diam.; internodes 0.8-2.2 cm long. Sterile bracts on the peduncle at the base tubular, in natural position seen from the side narrowly ovate, 1.6-4.0 by 0.5-1.4 cm; apex acuminate to cuspidate. Floral bracts patent, in natural position seen from the side narrowly ovate, 1-2.7 by 0.3-0.9 cm; apex acuminate; nerves many. Pedicel 0. 6-2 by 0.1-0.2 cm. Ovary 0.3-0.6 by 0.1-0.2 cm. Median sepal narrowly triangular to narrowly elliptic, 1.8-2.1 by 0.3-0.8 cm; apex acuminate to cuspidate; main nerves 11-15. Lateral sepals narrowly ovate, 1.6-2.3 by 0.3-0.7 cm; base broadly obliquely attached; apex acuminate to cuspidate, developed into a wing c. 0.15 cm high; main nerves 7-13. Petals with similar consistency as the sepals, narrowly obovate to narrowly ovate, 1.7-2.3 by 0.3-0.6 cm; base broadly attached, slightly swollen; top rounded to acuminate; main nerves 7-11. Lip 1.8-2.5 by 0.7-1.5 cm over the lateral lobes when flattened. Hypochile 1-1.4 cm by 1-1.5 cm; lateral lobes more or less erect, projecting forwards, with rounded top, c. 0.1 by 0.3 cm; nerves many, fine; keels 3 over the entire length of the hypochile, at the base highest, plate-like, in the front part of the hypochile descending to c. 0.05 cm and there sometimes on either side flanked with a short additional keel with straight or undulating margin. Epichile about broadly ovate to elliptic to rhomboid with rounded corners, c. 0.6-0.9 by 0.5-0.8 cm; top obtuse to truncate, sometimes acute; keels 5, with undulating margin, the central 3 continued from those on the hypochile, the lateral ones as long as central keel or c. 0.3 cm shorter, often continuing somewhat on the hypochile, sometimes with additional short ones at the junction with the hypochile. Column 1.2-1.6 by 0.2-0.5 cm; margin narrowly wing-like c. 0.1 cm wide; top irregular, 2-lobed to 6-lobed; column-foot not present; rostellum pronounced, c. 0.1 by 0.2 cm. Anther about orbicular, c. 0.2 by 0.2 cm; top more or less emarginate; pollinia 8, ovate, laterally compressed. Fruit beaked, the perianth and column long persistent; body ellipsoid, 1.5-2 by c. 1 cm, with 3 grooves which widen near the top, margin of the grooves somewhat swollen; valves about smooth, midrib faint.
(After Sulistiarini, Hadiyati and De Vogel, unpublished).

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