Schizachyrium perplexum

HABIT Annual. Culms 10–20 cm long; 0.4 mm diam.; 5–8 -noded. Culm-internodes distally with pubescent line. Lateral branches ample. Leaf-sheaths wider than blade at the collar; keeled. Ligule an eciliate membrane; 0.7–0.8 mm long. Leaf-blades conduplicate; 1.7–2.7 cm long; 1–1.5 mm wide. Leaf-blade surface scaberulous. Leaf-blade margins scaberulous. Leaf-blade apex obtuse.

INFLORESCENCE Inflorescence composed of racemes; subtended by a spatheole. Spatheole linear, or lanceolate; 1.8–3.2 cm long. Peduncle 2–4.5 cm long.

Racemes 1; single; 1.3–1.8 cm long; 0.7–0.9 mm wide; bearing 3–5 fertile spikelets on each. Rhachis fragile at the nodes; semiterete; pilose on surface; glabrous on margins, or ciliate on margins. Rhachis internodes clavate. Rhachis internode tip crateriform; with scarious rim.

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels clavate; glabrous, or ciliate.

STERILE SPIKELETS Companion sterile spikelets rudimentary; comprising 2 unequal glumes without lemmas; linear; 0.6–0.7 mm long; shorter than fertile; deciduous with the fertile. Companion sterile spikelet glumes chartaceous; awned; one glume awned; with 2–16 mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 3.5–4.5 mm long; 0.6–0.7 mm wide; falling entire; deciduous with accessory branch structures. Spikelet callus 0.3–0.4 mm long; pilose; base obtuse; with circular scar. Spikelet callus hairs 2 mm long.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; chartaceous; 2-keeled; keeled all along; keeled frontally; winged on keel; winged narrowly; winged all along. Lower glume intercarinal veins obscure; 3 in number. Lower glume surface convex; pilose. Lower glume hairs 3.5 mm long. Upper glume lanceolate; membranous; 1-keeled; keeled above; 1 -veined. Upper glume lateral veins absent. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 0.75 length of spikelet; hyaline; 0 -veined; without midvein; without lateral veins. Fertile lemma oblong; hyaline; without keel; 1 -veined. Lemma apex lobed; 2 -fid; incised 0.9 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 16–21 mm long overall; with twisted column. Column of lemma awn 6–7 mm long; glabrous. Palea absent or minute.

FLOWER Anthers 0.4 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 1.6–2.2 mm long. Embryo 0.5 length of caryopsis.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Blake 1994.

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