Bambusa sp. (TH) 2

Thai name: ไผ่แข่่กวาง (phai khae kwang).

Distribution: THAILAND (North), wild.

Specimen: BS-0119 [C4 ] (living plant), northern Thailand, wild, without precise locality, in cultivation in nursery เวียงดอกไม้หอมเชียงใหม่, Doi Saket District, Chiang Mai Province, received as "ไผ่แข่่กวาง" (SS-062) from ศ. ส. , 26 Aug. 2013.

Characteristics: Habit unicaespitose, dense. Rhizome pachymorph, short [n.v.]. Culms straight, erect, slightly bending outwards above; the ultimate size of length and diameter not yet known. Young shoots conical, sheaths green, blades erect; emerge late. Culm-internodes terete, ca. 20 cm long, medium green, glabrous; walls moderately thick. Culm-nodes glabrous, smooth, not prominent; nodal line horizontal; sheath scar marginally protruding, ca. 0.5 mm; supranodal line obscure, without a ridge, ca. 6 mm above the nodal line; with a narrow white transverse band when young just below the node but with a short distance from the nodal line, fading soon; aerial roots none. Branch-buds solitary, dome-shaped, from the basal node up. Branches several, subequal, central one slightly dominant; unbranched on the basal and lower culm; branching intravaginal; rebranching. Culm-leaves deciduous, late-deciduous on unbranched nodes of the basal and lower culm. Culm-leaf sheaths shorter than the internode, thickly papery, light straw-colored when dry, with a few dark spots; pale hirsute when young, becoming glabrous with age; margins pale ciliate. Culm-leaf auricles outward-bent bristly lobes, rounded to sickle-shaped. Culm-leaf ligule low. Culm-leaf blades erect, persistent or late caducous, lanceolate. Foliage-leaves 7–9 (12) per branchlet. Foliage-leaf sheaths medium green to light green and thinly farinose when young, glabrous; apex truncate; margins short pale ciliate. Foliage-leaf auricles small rounded to ovate glabrous and slightly vaulted lobes, brownish when young; margins with pale bristles, initially long and waved, caducous, but short stumps usually remain attached. Foliage-leaf ligule inconspicuous, margin entire; outer ligule a low glabrous ridge. Foliage-leaf blades long-lanceolate, 12–23 × 2–3 cm, upper surface glabrous and medium green, lower surface glabrous or puberulent and green with a slightly bluish tint; base rounded to wedge-shaped, upper surface with a few short soft pale hairs near the pseudopetiole when young; apex acuminate to attenuate; margins antrorsely scabrous; midvein proximally slightly prominent, light green; pseudopetiole short, 1–2 mm long. Flowers and seeds are unknown.

Comments: The plant is slow-growing. In September 2022, the plant was still too small to examine all vegetative characteristics sufficiently.