Digitaria purpurea

HABIT Perennial; caespitose. Butt sheaths pilose; persistent and investing base of culm; with compacted dead sheaths. Culms erect; 40–80 cm long. Lateral branches lacking. Ligule an eciliate membrane. Leaf-blades filiform, or linear; involute; 7–13 cm long; 0.5–3 mm wide. Leaf-blade surface pilose. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1–5; single, or paired, or digitate; flexuous; unilateral; 3.5–7 cm long; simple, or secondarily branched. Rhachis angular; smooth on margins. Spikelet packing lax.

Spikelets in pairs, or in threes. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 3–4 mm long; falling entire.

GLUMES Glumes one the lower absent or obscure; shorter than spikelet; thinner than fertile lemma. Upper glume ovate; 2–3 mm long; 0.66–0.75 length of spikelet; membranous; without keels; 3 -veined. Upper glume surface pubescent; hairy between veins. Upper glume hairs black. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret ovate; 1 length of spikelet; membranous; 5 -veined; pubescent; hairy between veins but central interspaces glabrous; bearing black hairs; acute. Fertile lemma ovate; 3–4 mm long; cartilaginous; much thinner on margins; dark brown; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

FLOWER Anthers 3; 2.5 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION South America: Brazil.

NOTES Paniceae. Renvoize 1997.

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