Description from Flora of China
Clavinodum T. H. Wen.
Shrubby to arborescent bamboos. Rhizomes leptomorph, with running underground stems. Culms diffuse, sometimes clustering; internodes not terete, flattened above branches; nodes ± elevated; intranode (3–)5 mm. Culm sheaths caducous or tardily deciduous, rarely persistent, leathery or papery; auricles and oral setae absent or sometimes weakly developed; blade spreading or reflexed, sometimes erect. Branches 3(–7) at each node in midculm, spreading. Leaf auricles and oral setae absent or weakly developed; blade small, transverse veins distinct. Inflorescence a raceme with 2 or 3(–6) spikelets, rarely a panicle with many spikelets, peduncle, axis, branches, and pedicels slender, glabrous, scabrous or pubescent along longitudinal angles, branches usually subtended by a scaly bract at base. Spikelets ± compressed at maturity, several to many florets; rachilla disarticulating below fertile florets, extended beyond palea of uppermost floret, internodes flattened or concave on side facing floret. Glumes (1–)3(–5), transitional with basal, sterile lemmas; lemma 7- to many veined, abaxially commonly puberulent and with distinct tessellation, adaxially slightly scabrous with minute setulae, apex acuminate with an awnlike point; palea conspicuously smaller than lemma or equaling in length but much narrower in upper florets, abaxially minutely setulate, 2-keeled, 2–4-veined between and beside keels, apex obtuse or emarginate; lodicules 3, membranous with thickened lower portion, 5–7-veined, margins ciliate, anterior pair of lodicules usually asymmetrical. Stamens 3 or 4(or 5). Ovary glabrous; style 1; stigmas (2 or)3, plumose.
Oligostachyum is similar to Acidosasa, from which it differs in having florets with no more than 5 stamens.
Taxa incertae sedis
Oligostachyum exauriculatum N. X. Zhao & Z. Yu Li in Z. Yu Li, Pl. Longqi Mountain, Fujian, China, 599. 1994.
无耳少穗竹 wu er shao sui zhu
Culms 3–4 m, (0.7–)1.2 cm in diam.; internodes initially dark green, white powdery, subcylindric, mostly 20–28 cm, shorter toward base, glabrous; nodes distinctly elevated; intranodes ca. 5 cm; branches mostly 3 per node, 5 or more at upper nodes. Culm sheaths deciduous, hardly spotted, thickly papery, abaxially sparsely reddish brown setulose; auricles and oral setae absent; blade erect, yellowish brown, triangular, 0.4–1.5 cm, base not narrowed. Leaves 2 or 3 per ultimate branch; sheath sparsely caducous ciliate; auricles and oral setae absent; ligule arcuate, 2–3 mm, margin subglabrous; blade linear-lanceolate, 10–18 × 1–1.5 cm, both surfaces subglabrous, base broadly cuneate, apex acuminate; lateral veins transverse, 4- or 5-paired. Inflorescence unknown.
● Montane forest margins; 1900–2000 m. Fujian (Jiangle).
The authors compared this species to Oligostachyum oedogonatum.
In addition, Oligostachyum yonganense Y. M. Lin & Q. F. Zheng (Fl. Fujian. 6: 689. 1995) was described from Fujian (Yongan). In the protologue it was compared with O. lanceolatum.
* At least 15 species:China.
(Authors: Wang Zhengping (王正平 Wang Cheng-ping); Chris Stapleton)