Digitaria michoacanensis

HABIT Perennial; caespitose. Rhizomes short; knotty. Butt sheaths purple; pilose. Culms erect; 15–30(–55) cm long; 2–3 -noded. Culm-internodes distally glabrous, or pubescent. Culm-nodes pubescent. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths 3–4(–7) cm long; longer than adjacent culm internode; glabrous on surface; outer margin hairy. Leaf-sheath auricles erect. Ligule an eciliate membrane; 0.5–0.6 mm long; white, or brown; erose. Leaf-blades lanceolate; 3.2–5.7(–10) cm long; 5–6 mm wide. Leaf-blade surface pilose, or hirsute (2–4 mm); hairy adaxially. Leaf-blade margins scaberulous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes. Peduncle pubescent above.

Racemes 2(–3); paired, or digitate, or borne along a central axis; appressed; unilateral; 2–6.5 cm long. Central inflorescence axis 1 cm long. Rhachis angular; 0.4–0.5 mm wide; scaberulous on margins, or scabrous on margins. Raceme-bases pubescent; hairy in axils (pulvini).

Spikelets in threes. Fertile spikelets pedicelled. Pedicels unequal; 1–4.5 mm long; ciliate; hairy above; tip discoid.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 2.6–2.7 mm long; 1.3–1.4 mm wide; falling entire.

GLUMES Glumes one to two the lower present in some spikelets; shorter than spikelet, or reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.3–0.5 mm long; 0.2 length of spikelet; hyaline; 0 -veined. Lower glume lateral veins absent. Lower glume surface pubescent; with clavate hairs. Lower glume apex truncate. Upper glume elliptic; 2–2.7 mm long; 0.66–0.9 length of spikelet; membranous; without keels; 3–5 -veined. Upper glume surface pubescent; hairy between veins; with capitate hairs. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 0.9 length of spikelet; membranous; 5 -veined; with unevenly spaced veins; pubescent; hairy between veins; with capitate hairs; acute. Fertile lemma elliptic, or ovate; 2.6–2.7 mm long; 1–1.1 mm wide; cartilaginous; much thinner on margins; light brown, or dark brown; without keel. Lemma surface papillose and striate. Lemma margins flat; covering most of palea. Lemma apex acute, or acuminate. Palea cartilaginous.

FLOWER Lodicules 2; united. Anthers 3; 1.3–1.4 mm long.

DISTRIBUTION North America: Mexico.

NOTES Paniceae. Sanchez-Ken 2014.

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