GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Peyritschia deyeuxioides

HABIT Perennial; caespitose. Culms decumbent; weak; 50–100 cm long. Culm-nodes glabrous. Lateral branches lacking. Leaf-sheaths glabrous on surface, or pubescent. Ligule an eciliate membrane; 0.5–3.5 mm long. Leaf-blades 8–16 cm long; 2–6 mm wide. Leaf-blade surface scabrous; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; nodding; 10–20 cm long; 1–4 cm wide; contracted about primary branches. Primary panicle branches ascending; 3–7 cm long; bearing spikelets almost to the base.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets cuneate; laterally compressed; 5–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.5 mm long; villous; hairy all along but hairs longer above; with 2–3 mm long hairs. Floret callus pubescent; disarticulating obliquely. Floret callus hairs 0.2–0.5 mm long.

GLUMES Glumes persistent; similar; reaching apex of florets; thinner than fertile lemma; shiny; gaping. Lower glume linear; 4.2–5.5 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume linear; 4.9–5.5 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 4.2–5 mm long; membranous; shiny; keeled; 5 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; 5–7 mm long overall; with twisted column. Palea gaping; 1 length of lemma; hyaline.

FLOWER Anthers 2; 1.5 mm long; yellow. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform. Endosperm soft.

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

NOTES Aveneae. Fl Costa Rica 1994.

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