Trisetum koidzumianum

HABIT Perennial; caespitose; clumped loosely. Rhizomes short. Culms erect; 12–25 cm long. Culm-internodes distally pilose. Leaf-sheaths pilose. Ligule an eciliate membrane; 1–2 mm long. Leaf-blades 5–6 cm long; 2–4 mm wide. Leaf-blade surface glabrous, or pilose.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate; dense; 5–9 cm long; 0.8–1.5 cm wide. Primary panicle branches 3–5 -nate. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with a barren rhachilla extension, or with diminished florets at the apex. Spikelets cuneate; laterally compressed; 4.5–5.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate; 3–3.5 mm long; 1 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume lanceolate; 3–3.5 mm long; 0.75–0.85 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 4 mm long; membranous; keeled; 5 -veined. Lemma apex dentate; 2 -fid; acute; awned; 1 -awned. Principal lemma awn dorsal; arising 0.25 way up back of lemma; geniculate; 5 mm long overall; with a straight or slightly twisted column. Palea gaping; hyaline.

FLOWER Anthers 3. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-temperate: eastern Asia.

NOTES Aveneae. Koyama 1994.

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