GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Schizachyrium dolosum

HABIT Annual. Culms 50–100 cm long; 0.35–0.8 mm diam.; 7–11 -noded. Lateral branches ample. Leaf-sheaths wider than blade at the collar; smooth. Ligule an eciliate membrane; 0.2–0.4 mm long. Leaf-blades conduplicate, or convolute; 2–6 cm long; 0.8–1.5 mm wide. Leaf-blade surface scaberulous; rough adaxially. Leaf-blade margins scaberulous; glabrous.

INFLORESCENCE Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; embraced at base by subtending leaf. Spatheole linear; 2.5–4.5 cm long. Peduncle 0.2–0.6 cm long.

Racemes 1; single; 1.75–2.5 cm long; 1–1.2 mm wide; bearing 4–7 fertile spikelets on each. Rhachis fragile at the nodes; semiterete; pilose on surface (below). Rhachis internodes oblong; 4–7 mm long. Rhachis internode tip crateriform; with scarious rim.

Spikelets squeezed between internode and pedicel; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels clavate; 4–7 mm long; ciliate; hairy below.

STERILE SPIKELETS Companion sterile spikelets rudimentary; comprising 2 unequal glumes without lemmas; linear; 1–1.5 mm long; shorter than fertile; deciduous with the fertile. Companion sterile spikelet glumes chartaceous; awned; one glume awned; with 12–18 mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; acute; 4.3–8 mm long; 0.55–0.9 mm wide; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 0.8–1.3 mm long; pilose; base obtuse; with elliptic scar. Spikelet callus hairs 1–1.5 mm long.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; 2-keeled; keeled above; keeled frontally. Lower glume intercarinal veins obscure; 2–3 in number. Lower glume surface convex; glabrous, or pilose; hairy below. Upper glume lanceolate; membranous; 1-keeled; keeled above; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent. Upper glume mucronate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 0.8 length of spikelet; hyaline; 0 -veined; without midvein; without lateral veins. Fertile lemma oblong; hyaline; without keel; 1 -veined. Lemma margins ciliolate. Lemma apex lobed; 2 -fid; incised 0.9 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 12–18 mm long overall; with twisted column. Column of lemma awn 5–8 mm long; glabrous. Palea absent or minute.

FLOWER Anthers 0.3–0.5 mm long.

FRUIT Caryopsis with adherent pericarp; linear; 2.3–2.5 mm long. Embryo 0.5 length of caryopsis.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Blake 1994.

ADDITIONAL CHARACTERS Spikelet callus furrowed.

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