Bambusa gurgandii

Type: Vietnam, Binh Duong Province: Phu An Bamboo Village, cult., 24 Nov. 2014, M. H. Diep, C. K. Le, J. Gurgand & al. MH 100, holoype (SING); cf. K. M. Wong & M. H. Diep, in Candollea 70(2), 2015: p. 215 [#1262].

Thai name: ไม้เซิม (mai soem) (Loei). — Mu Chakkrapong, pers. comm., Facebook, 2 Oct. 2021.

Lao name: ໄມ້ພາງ (mai phang) — Mu Chakkrapong, pers. comm., Facebook, 12 Oct. 2021.

Vietnamese names: lồ ô vàng, lồ ô đen, which translated mean "giant umbrella yellow" and "giant umbrella black" respectively.

Distribution: THAILAND (North-East): Loei Province: Dan Sai District (อ. ด่านซ้าย) and Phu Ruea District (อ. ภูเรือ), wild (Mu Chakkrapong, pers. comm., Facebook, 2 Oct. 2021). — LAOS: Oudomxay Province (ແຂວງອຸດົມໄຊ), wild (Mu Chakkrapong, l.c.). — VIETNAM: Thừa Thiên Huế Province: Nam Đông, cultivated; Bình Dương Province: Phú An: Phu An Bamboo Village, cultivated.

Description: "Clumping bamboo to c. 15 m tall. Culms plain green, to 10 cm diameter, quite stiffly erect and apically only slightly arching, with well-spaced culms about 10–30 cm apart. Culm internodes with a conspicuous covering of appressed pale hairs all over the basal few internodes, this becoming scantier and more restricted to the internode base towards mid-culm, with a consistent narrow ring of dense appressed pale hairs just above each node; and a slight white-waxy bloom all over. Culm sheaths on mature culms 22–32 cm long, mainly pale green, infused with yellowish green at the top of the sheath proper; with scattered pale brown to medium brown or black appressed hairs and a slight white-waxy bloom all over the back; basal part at the sheath insertion with a 2–3 mm narrow ring-like band of dense spreading medium to dark brown hairs 2–3 mm long; blade 5.5–24 cm long, broad to narrowly triangular, erect but loosely held (not tightly appressed) against the next sheath or internode, medium green, with a slight white-waxy bloom on the outer (abaxial) side, with fine 2–4 mm long sinuous pale brown bristles at the base of the margin, the blade base with a few corrugations as it continues with only slight constriction into laterally elongate, spreading lobe-like auricles; auricles 5–10 mm high, protruding to 1–1.5 cm laterally from the sheath margin and slightly downcurved at the end, purplish brown, with sinuous bristles on the edge 5–7 mm long; ligule a leathery low subentire rim 1–2.5 mm high with 2–5 mm long narrowly triangular teeth on the margin. Branch buds solitary at each branching node, the prophyll broadly dome-shaped with fused margins and resembling a broad hood around the bud. Branches at mid-culm with the primary axis developed. Branch leaves mostly c. 10–23 cm long, to 1.5–2.6 cm broad, dark green, slightly glaucous on the lower (abaxial) surface, glabrous on both surfaces; auricles conspicuous laterally spreading narrow lobes 0.5–1 mm high and 3–5 mm long, slightly downcurved at the end, margins with fine spreading bristles 5–7 mm long; ligule inconspicuous; sheath glabrous; the abaxial side of the sheath apex developing a scale-like callus 1–2 mm long with subentire-erose margin. ... [flowers and seeds described]". — K. M. Wong & M. H. Diep, in Candollea 70(2), 2015: p. 211-218 [#1262].

Images: Photos and line drawings in K. M. Wong & M. H. Diep, l.c., 2015 [#1262]. Photo in: K. M. Wong & al., A subtribal classification of Malesian and Southwest Pacific woody bamboos …, Sandakania No. 22, 2016, p. 18, fig. 1A (branch complement) [#1248].

Uses: No known records.