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.

Exotheca abyssinica

HABIT Perennial; caespitose. Culms 30–200 cm long; 1–3 mm diam. Leaf-sheath auricles erect; 3–18 mm long. Ligule an eciliate membrane; 3–18 mm long; truncate. Leaf-blades 5–45 cm long; 1–4 mm wide.

INFLORESCENCE Synflorescence compound; scanty. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole linear; 8–12 cm long; scarious. Peduncle scaberulous above.

Racemes 2; paired; end to end; 2.5 cm long; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis fragile at the nodes. Rhachis hairs 2 mm long. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases filiform; unequal (the longer measured); 15–25 mm long; glabrous.

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

STERILE SPIKELETS Basal sterile spikelets well-developed; 4 in number (lower raceme); 4 in upper raceme; forming an involucre about the fertile; male; equalling fertile. Basal sterile spikelet glumes glabrous; lower glume muticous.

Companion sterile spikelets well-developed; male; lanceolate; 14–16 mm long; as long as fertile; deciduous with the fertile. Companion sterile spikelet glumes chartaceous; muticous, or awned; one glume awned; with 0–10 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; subterete; 12–15 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 3–4 mm long; pilose; base pungent; attached obliquely. Spikelet callus hairs red.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; much thinner above; dark brown; without keels; 9 -veined. Lower glume lateral veins ribbed. Lower glume surface pubescent. Lower glume hairs white, or yellow. Lower glume apex dentate; 2 -fid. Upper glume lanceolate; coriaceous; much thinner above; without keels; 3 -veined. Upper glume surface glabrous, or pubescent. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 12–13 mm long; hyaline; 2 -veined; ciliolate on margins; obtuse. Fertile lemma linear; 7 mm long; hyaline; without keel; 3 -veined. Lemma margins ciliolate. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 60–100 mm long overall; with twisted column. Column of lemma awn pubescent. Palea obovate; hyaline. Palea keels ciliate.

DISTRIBUTION Africa: west-central tropical, northeast tropical, east tropical, and southern tropical. Asia-tropical: Indo-China.

NOTES Andropogoneae. FTEA.

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