Digitaria costaricensis

HABIT Perennial. Culms decumbent; 40–80 cm long; 1–3 mm diam. Lateral branches ample. Leaf-sheaths pilose; with tubercle-based hairs and reflexed hairs. Ligule an eciliate membrane; 1.5–2.5 mm long; erose. Leaf-blades 8–15 cm long; 3.5–7 mm wide. Leaf-blade surface pubescent; densely hairy; hairy on both sides.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 4–7; digitate; unilateral; 5–11 cm long; with branchlets at base of longer racemes. Central inflorescence axis 2–3 cm long. Rhachis angular; scabrous on margins. Spikelet packing lax.

Spikelets appressed; in pairs. Fertile spikelets pedicelled. Pedicels unequal; 0.5–0.7 mm long, or 2–3 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; acute; 3.5–4 mm long; falling entire.

GLUMES Glumes two; reaching apex of florets; thinner than fertile lemma. Lower glume oblate; 0.3 mm long; 0.1 length of spikelet; hyaline; 0 -veined. Lower glume lateral veins absent. Lower glume apex truncate. Upper glume elliptic; 1 length of spikelet; membranous; without keels; 5–7 -veined. Upper glume surface pubescent; hairy between veins. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; membranous; 7–9 -veined; with equidistant veins; pubescent; hairy between veins but central interspaces glabrous; acute. Fertile lemma elliptic; 3–3.2 mm long; cartilaginous; much thinner on margins; grey; without keel; 3 -veined. Lemma surface striate. Lemma margins flat; covering most of palea. Palea cartilaginous.

FLOWER Anthers 3; 0.9–1.5 mm long; purple.

DISTRIBUTION South America: Mesoamericana.

NOTES Paniceae. Fl Costaric 1994.

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