GrassBase - The Online World Grass Flora




Ichnanthus annuus

HABIT Annual. Culms geniculately ascending; slender; 15–40 cm long; 5–11 -noded; rooting from lower nodes. Culm-internodes striate; distally pilose (sparsely). Lateral branches sparse. Leaf-sheaths tight; keeled; pilose. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs; 0.5 mm long. Leaf-blade base cordate; symmetrical; with a brief petiole-like connection to sheath. Leaf-blades ovate; 2–9 cm long; 10–25 mm wide; membranous. Leaf-blade venation with distinct cross veins. Leaf-blade surface scaberulous; rough adaxially; pilose. Leaf-blade margins cartilaginous; scabrous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle; terminal, or terminal and axillary (occasionally).

Panicle open; 3–11 cm long; with spikelets clustered towards branch tips (in groups of 2–9 spiklets). Primary panicle branches simple. Panicle axis pilose.

Spikelets ascending; in pairs. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets. Spikelets lanceolate; laterally compressed; acute; 4–5 mm long; falling entire. Floret callus without wings.

GLUMES Glumes similar; shorter than spikelet, or reaching apex of florets; thinner than fertile lemma. Lower glume ovate; clasping; 0.66–0.75 length of spikelet; cartilaginous; 1-keeled; 3 -veined. Lower glume lateral veins ribbed. Lower glume surface scabrous; glabrous. Lower glume apex acuminate to setaceously attenuate. Upper glume lanceolate; 0.9–1 length of adjacent fertile lemma; 1 length of spikelet; cartilaginous; 5 -veined. Upper glume lateral veins ribbed. Upper glume surface pilose (sparsely). Upper glume apex acuminate.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret 1 length of spikelet; cartilaginous; 5 -veined; ribbed; pilose (sparsely). Fertile lemma 2 mm long; cartilaginous (thinly); shiny. Lemma margins involute. Lemma apex acute; without appendage. Palea cartilaginous (thinly).

FLOWER Anthers 3; 1.5 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: Brazil (Maranhao).

NOTES Paniceae. SAR 2003.
