Peyritschia howellii

HABIT Perennial; caespitose; clumped loosely. Culms erect; slender; 70 cm long. Culm-internodes distally glabrous. Leaf-sheaths striately veined; glabrous on surface, or pubescent. Ligule an eciliate membrane; 1–2 mm long. Leaf-blades 10–15 cm long; 1–3 mm wide. Leaf-blade surface smooth, or scaberulous; rough adaxially; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate; 10–15 cm long. Primary panicle branches appressed; 1–3 cm long. Panicle axis smooth, or scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 4–4.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1 mm long; pilose. Floret callus pubescent. Floret callus hairs 0.2–0.5 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet, or reaching apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 4 mm long; 1 length of upper glume; hyaline; 1-keeled; 1 -veined. Lower glume primary vein smooth, or scaberulous. Lower glume lateral veins absent. Lower glume apex setaceously attenuate. Upper glume lanceolate; 4 mm long; 0.75 length of adjacent fertile lemma; hyaline; 1-keeled; 3 -veined. Upper glume primary vein scaberulous. Upper glume apex acuminate.

FLORETS Fertile lemma elliptic; 3–3.5 mm long; membranous; keeled; 5 -veined. Lemma surface glabrous. Lemma apex awned; 1 -awned. Principal lemma awn dorsal; arising 0.66 way up back of lemma; geniculate; 5 mm long overall; with twisted column. Rhachilla extension 1 mm long; pilose; with 1 mm long hairs.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: western South America.

NOTES Aveneae. Hitchcock 2001.

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