Hyperthelia cornucopiae

HABIT Annual. Culms 200–450 cm long; 4–9 mm diam.; with prop roots. Leaf-sheaths glabrous on surface. Leaf-sheath auricles absent, or erect; 0–2 mm long. Ligule an eciliate membrane; 2–5 mm long; scarious; obtuse. Leaf-blade base tapering to the midrib. Leaf-blades 40–80 cm long; 12–25 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Synflorescence compound; paniculate; 30–40 cm long. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole lanceolate; 5.5–9 cm long; scarious; glabrous. Peduncle glabrous, or pilose above.

Racemes 2; paired; deflexed; 1.5–4 cm long; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes filiform. Rhachis internode tip oblique; flat. Raceme-bases filiform; unequal (the longer measured); 1–3 mm long; glabrous; extended into a flask-like appendage; with 5–10 mm long appendage.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; 4 mm long; ciliate; tip oblique.

STERILE SPIKELETS Basal sterile spikelets well-developed; lower raceme 2 in number; 0 in upper raceme; male; lanceolate, or ovate; 8–25 mm long; equalling fertile. Basal sterile spikelet glumes glabrous; lower glume muticous.

Companion sterile spikelets well-developed; male; lanceolate; 8–25 mm long; as long as fertile; deciduous with the fertile. Companion sterile spikelet callus cuneate; 1–2.5 mm long; acute. Companion sterile spikelet glumes coriaceous; awned; one glume awned; with 2–15 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 linear; subterete; 8–18 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 2.5–5 mm long; bearded; base pungent; attached obliquely. Spikelet callus hairs white, or dark brown.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; much thinner above; without keels; 6–10 -veined. Lower glume surface with a longitudinal median groove; pubescent; hairy generally, or below. Lower glume hairs dark brown. Lower glume apex dentate; 2 -fid; mucronate. Lower glume awn 1–2 mm long. Upper glume oblong; coriaceous; without keels; 3 -veined. Upper glume awned. Upper glume awn 1–9 mm long.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; hyaline; 2 -veined; ciliate on margins. Fertile lemma linear; 4–8 mm long; hyaline; without keel; 3 -veined. Lemma margins ciliate. Lemma apex lobed; 2 -fid; incised 0.25 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 60–150 mm long overall; with twisted column. Column of lemma awn hirtellous. Palea absent or minute.

FRUIT Caryopsis 6 mm long.

DISTRIBUTION Africa: northeast tropical.

NOTES Andropogoneae. WDC.

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