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.

Andropogon crucianus

HABIT Perennial; caespitose. Butt sheaths purple. Basal innovations flabellate. Culms erect; 150 cm long. Ligule an eciliate membrane. Leaf-blades flat, or conduplicate; 25–45 cm long; 2–4 mm wide; firm; glaucous. Leaf-blade surface glabrous. Leaf-blade apex abruptly acute; hooded.

INFLORESCENCE Synflorescence compound; linear; 25 cm long; dense. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole linear. Peduncle tipped by a glumaceous appendage (5–10mm long).

Racemes 1; paired, or digitate; 2–2.5 cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear. Rhachis internode tip transverse; cupuliform; with simple rim.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; 3–4 mm long; shorter than fertile, or as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; glabrous; acute; muticous. Companion sterile spikelet lemmas enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 3–3.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; 2-keeled; keeled laterally. Lower glume intercarinal veins absent. Lower glume surface flat. Upper glume linear; coriaceous; 1-keeled. Upper glume muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline. Fertile lemma lanceolate; hyaline; without keel. Lemma apex muticous.

DISTRIBUTION South America: western South America.

NOTES Andropogoneae. Gr Bolivia 1997.

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