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.

Diheteropogon hagerupii

HABIT Annual. Culms erect; 100–150 cm long. Ligule an eciliate membrane. Leaf-blade base cordate, or amplexicaul. Leaf-blades 5–20 cm long; 5–20 mm wide.

INFLORESCENCE Inflorescence composed of racemes; terminal and axillary.

Racemes 2; paired; 2–6 cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear. Rhachis internode tip crateriform; with simple rim. Raceme-bases linear.

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

STERILE SPIKELETS Basal sterile spikelets well-developed; 2 in number (lower raceme); 0 in upper raceme; sessile and pedicelled; equalling fertile.

Companion sterile spikelets well-developed; male; linear, or lanceolate; dorsally compressed; 7–12 mm long; longer than fertile; deciduous with the fertile. Companion sterile spikelet glumes chartaceous; keeled; wingless; distinctly veined; awned; one glume awned; with 1–12 mm long awn. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 6–10 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1–3 mm long; pilose; base pungent; inserted.

GLUMES Glumes dissimilar; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; 2-keeled; keeled dorsally; keeled obtusely. Lower glume lateral veins several in each keel (3 in each); intercarinal veins absent. Lower glume surface with a longitudinal median groove, or deeply depressed. Upper glume lanceolate; 3 -veined. Upper glume surface pubescent.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret hyaline. Fertile lemma oblong; 4.5 mm long; membranous; without keel; 3 -veined. Lemma apex lobed; 2 -fid; incised 0.25 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; bigeniculate; 60–110 mm long overall; with twisted column. Column of lemma awn hirtellous; with 0.5 mm long hairs. Palea absent or minute.

DISTRIBUTION Africa: west tropical and west-central tropical.

NOTES Andropogoneae. WDC.

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