Micropera

Key to the SpecieS of Micropera View in CoL in Thailand

1. Lip pinkish purple; rostellum>4 times longer than column height, sigmoid in lateral view, not strongly twisted sideways........... M. rostrata View in CoL

1. Lip yellow; rostellum <3.5 times as long as column height, straight or strongly twisted sideways............................................................... 2

2. Rostellum strongly twisted sideways (through about 90 degrees)................................. M. obtusa View in CoL

2. Rostellum straight or only slightly twisted sideways............................................................. 3

3. Side lobes of labellum conspicuous, more or less quadrangular .....................................................4

3. Side lobes of labellum inconspicuous............... 5

4. Spur strongly incurved....................... M. callosa View in CoL

4. Spur (sub-)straight ............................. M. pallida View in CoL

5. Mid-lobe of labellum with a raised callus ......................................................... M. fuscolutea View in CoL

5. Mid-lobe of labellum without distinct callus .... ....................................................... M. thailandica View in CoL Micropera callosa (Blume) Garay, Bot. Mus. Leafl. View in CoL 23: 186. 1972. Cleisostoma callosum Blume, Bijdr. Fl. Ned. Ind. View in CoL 364. 1825. Sarcanthus callosus (Blume) Rchb.f., Bonplandia (Hannover) View in CoL 5: 41. 1857. Camarotis callosa (Blume) J.J.Sm., Natuurk. Tijdschr. Ned.-Indië View in CoL 72: 97. 1912. Type: INDONESIA, Java, Pantjar, Blume , C.L. s.n. (holo L [L0061626 digital image!]). FiGS. 2 View Fig a-b & 3

Stem up to 40 cm long, up to 0.6 cm in diam., covered by the rugose leaf sheaths; roots up to 0.35 cm diam. Leaves 2–3 cm apart, oblong-linear, 11–13 × 1.8–2 cm, apex unequally bilobed with rounded lobes, fleshy. Inflorescences upright, 15–21 cm long, 18–30-flowered; peduncle 5.5– 10 cm long, with 2–3 sheathing peduncle scales 4–8 mm long; rachis 8–10 cm long, unbranched, ridged; bracts broadly triangular, 1–1.5 × 2.5–3 mm, obtuse. Flowers non resupinate, sepals and petals yellow with brownish red margin, lip orange yellow, sidelobe pale yellow, column white or cream; pedicel and ovary 9–11 mm long. Dorsal sepal oblanceolate, 7–7.3 × 2.8–3 mm, apex broadly obtuse, concave, fleshy, abaxial surface with scattered dark brown scale-hairs, adaxial surface glabrous; lateral sepals oblanceolate, 5.7–6 × 3.4–3.5 mm, adnate to column-foot, adaxial surface with dark brown scale-hairs, abaxial surface glabrous. Petals oblong-elliptic, up to 5.7–6 × 1.6– 1.9 mm, obtuse to acute, slightly falcate, glabrous. Labellum fleshy, tubular, strongly incurved at distal part, 3.4–3.6 mm long, 7–7.5 mm high, distinctly 3-lobed; lateral lobes somewhat quadrangular, 3.3–3.5 × 2.9–3 mm, upper edges erose, with a small and rounded callus on each side; mid-lobe broadly triangular, thickened, 1–1.2 × 1.8–2 mm, apex acute with narrow conical callus adaxially; spur 3.7–4 mm long, apex narrowly rounded, with longitudinal septum, 1–1.2 mm high and an oblong, upright, horn-like, triangular, bilobed callus at base of mid lobe. Column rather stout, 3–3.3 mm long; rostellum beak-like, 1–1.1 mm long, slightly twisted. Anther 1.8 – 2 × 1.7–1.9 mm, with short beak. Fruit not seen.

Flowering & fruiting: Flowering in August; fruit not seen.

Habitat: Epiphyte on Durian trees.

Distribution: Borneo, Java, Sumatra, and Thailand.

Specimen examined: THAILAND, Yala, Betong,

Ban Chantharat, N 5 o 47’35”, E 101 o 10’21”, 230 m, 24.08.2013, J GoogleMaps . Wai 2320 (PSU).

Notes: This species is a new record for Thailand and mainland Southeast Asia.