Panicum trichanthum

HABIT Perennial. Culms rambling; 100–150 cm long; 1.5–2.5 mm diam.; rooting from lower nodes. Culm-internodes distally glabrous. Culm-nodes brown; glabrous. Lateral branches ample. Leaf-sheaths glabrous on surface; outer margin hairy. Ligule an eciliate membrane; 0.2–0.3 mm long. Collar pilose. Leaf-blade base cordate; with a brief petiole-like connection to sheath; petiole 0.1–0.2 cm long. Leaf-blades lanceolate; 5.5–13 cm long; 8–23 mm wide. Leaf-blade surface glabrous, or pubescent.

INFLORESCENCE Inflorescence a panicle.

Panicle open; obovate; 17–27 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels flexuous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; dorsally compressed; subacute; 1.2–1.6 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.2–0.4 mm long; 0.15–0.25 length of spikelet; membranous; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1.2–1.6 mm long; 1 length of spikelet; membranous; without keels; 5 -veined. Upper glume surface tuberculate (papillose). Upper glume apex acute.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 4 mm long; 1 length of spikelet; membranous; 5 -veined; acute. Fertile lemma ovate; dorsally compressed; 2–2.5 mm long; indurate; shiny; without keel. Lemma margins involute. Palea involute; indurate.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp; oblong; 0.8 mm long; light brown.

DISTRIBUTION North America: Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, Brazil, and southern South America.

NOTES Paniceae. Fl Costa Rica 1994.

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