Trisetum serpentinum

HABIT Perennial; caespitose; clumped loosely. Culms 25–50 cm long. Leaf-sheaths 1–3 cm long; pubescent. Ligule a ciliolate membrane; 0.4–0.8 mm long; erose. Leaf-blades involute; 2–16 cm long; 0.5–1 mm wide; dark green. Leaf-blade surface smooth, or scaberulous; rough abaxially, or on both sides. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence a panicle. Peduncle smooth; glabrous.

Panicle open; linear, or lanceolate; 2–10 cm long; 0.5–2 cm wide; contracted about primary branches. Primary panicle branches ascending, or spreading; bearing spikelets almost to the base. Panicle axis scaberulous. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 4–6.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pubescent; with 0.2–0.8 mm long hairs. Floret callus pubescent. Floret callus hairs 0.2 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet, or reaching apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume lanceolate, or oblong; 0.66–0.75 length of upper glume; membranous; 1-keeled. Lower glume apex acute, or acuminate. Upper glume lanceolate, or elliptic; membranous; 1-keeled. Upper glume apex acute, or acuminate.

FLORETS Fertile lemma elliptic; 3–4.5 mm long; membranous; shiny; keeled; 5 -veined. Lemma surface papillose. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.75 way up back of lemma; curved; 3–4 mm long overall. Palea gaping; hyaline. Palea keels scaberulous.

FLOWER Lodicules 2; 1 mm long. Anthers 3; 1.5 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Australasia: New Zealand.

NOTES Aveneae. Edgar 2000.

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