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.

Anadelphia bigeniculata

HABIT Annual. Culms 30–60 cm long. Ligule a ciliolate membrane; 1–2 mm long; truncate, or acute. Leaf-blades 8–30 cm long; 1–2 mm wide. Leaf-blade surface scaberulous. Leaf-blade margins scaberulous.

INFLORESCENCE Synflorescence compound; paniculate; 15–25 cm long; lax. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; exserted. Spatheole linear; 1.5–2.5 cm long; scarious. Peduncle 2–3 cm long; scaberulous above.

Racemes 1; single; 1 cm long; bearing few fertile spikelets; bearing 2–4 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Spikelet packing lax. Rhachis internodes filiform; 2 mm long. Rhachis internode tip oblique.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels filiform; 1.5 mm long; ciliate.

STERILE SPIKELETS Companion sterile spikelets represented by barren pedicels, or well-developed; male; lanceolate; 5 mm long; as long as fertile; separately deciduous. Companion sterile spikelet callus cuneate; 0.5 mm long; obtuse. Companion sterile spikelet glumes coriaceous; glabrous; setaceously attenuate; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes; 3 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 4–5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus square, or oblong; 0.2 mm long; pilose; base obtuse; attached obliquely. Spikelet callus hairs dark brown.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma; shiny. Lower glume oblong; 1 length of spikelet; coriaceous; dark brown; without keels; 7 -veined. Lower glume lateral veins obscure. Lower glume surface asperulous; rough above. Lower glume apex dentate; 2 -fid. Upper glume oblong; without keels; 3 -veined. Upper glume apex entire; awned; 1 -awned. Upper glume awn 3.5–6 mm long.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 3 mm long; hyaline; 2 -veined; ciliate on margins. Fertile lemma linear; 3 mm long; hyaline; without keel; 1 -veined. Lemma apex lobed; 2 -fid; incised 0.25 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; bigeniculate; 14–22 mm long overall; with twisted column. Column of lemma awn 7–9 mm long; glabrous. Palea absent or minute.

FLOWER Lodicules 2; cuneate; 0.2 mm long; fleshy; truncate. Anthers 3; 1.5–1.8 mm long.

DISTRIBUTION Africa: west tropical.

NOTES Andropogoneae. WDC.

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