Chrysopogon tenuiculmis

HABIT Perennial. Culms 30–60(–100) cm long. Ligule a fringe of hairs; 0.2–0.6 mm long. Leaf-blades conduplicate; 5–13 cm long; 2–3 mm wide. Leaf-blade surface glabrous, or pilose; hairy adaxially.

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme.

Panicle open; 5–8 cm long; 1–2.5 cm wide; bearing few spikelets. Primary panicle branches not whorled, or whorled at lower nodes; simple; 1.4–2.5 cm long.

Racemes bearing a triad of spikelets; 1 fertile spikelets on each. Rhachis obsolete. Raceme-bases filiform; 8–15 mm long.

Spikelets in threes. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Pedicels linear; 2.6–4 mm long; 0.66 length of fertile spikelet; smooth; glabrous.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; dorsally compressed; (4.5–)5.25–7(–8.25) mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; smooth, or scaberulous; puberulous; muticous, or mucronate, or awned; one glume awned; with 0–4.5 mm long awn. Companion sterile spikelet lemmas 1; enclosed by glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; (4.1–)5.25–6(–6.5) mm long; falling entire; deciduous with accessory branch structures. Spikelet callus oblong; 1.5–2 mm long; pilose; base pungent; attached obliquely. Spikelet callus hairs yellow; 1.9–2.25 mm long.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 5–8 mm long; 1 length of spikelet; cartilaginous; without keels; 5–7 -veined. Lower glume surface convex; smooth, or spinose; hispidulous; hairy above; with tubercle-based hairs. Lower glume apex entire, or dentate; 2 -fid; obtuse; muticous, or mucronate, or awned; 1 -awned. Lower glume awn 0–3 mm long. Upper glume lanceolate; 1-keeled; 3–5 -veined. Upper glume primary vein ciliolate. Upper glume awned; 1 -awned. Upper glume awn 2.6–8.6 mm long; glabrous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; hyaline; 2 -veined. Fertile lemma oblong; hyaline; without keel. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 14–25 mm long overall; clearly exserted from spikelet; with twisted column. Column of lemma awn puberulous; with 0.15 mm long hairs.

FLOWER Lodicules 2; glabrous. Anthers 3; 1.5–2.25 mm long (sessile), or 2.1–2.8 mm long (pedicelled).

DISTRIBUTION Asia-tropical: Malesia.

NOTES Andropogoneae. Veldkamp 1998.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.