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.

Eragrostis petrensis

HABIT Perennial; caespitose. Butt sheaths coriaceous; yellow; glossy. Culms erect; 40–80 cm long. Leaf-sheath oral hairs ciliate. Ligule a fringe of hairs. Leaf-blades involute; 10–35 cm long; 2–2.5 mm wide; stiff. Leaf-blade surface glabrous to pilose; densely hairy.

INFLORESCENCE Inflorescence a panicle.

Panicle open; pyramidal; interrupted; 11–28 cm long. Primary panicle branches whorled at most nodes; bearing spikelets almost to the base. Panicle axis glabrous to pilose. Panicle branches bearded in axils.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 4–9 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 3–6 mm long; 1–2 mm wide; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes similar; shorter than spikelet. Lower glume ovate; 1.5–2.3 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1.5–2.3 mm long; 0.75–0.9 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma ovate; 1.8–2.5 mm long; membranous; purple; suffused with last colour; keeled; 3 -veined. Lemma lateral veins distinct. Lemma surface scaberulous. Lemma apex acute. Palea 1.8–2 mm long; 2 -veined. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 0.7–0.8 mm long; yellow, or purple.

FRUIT Caryopsis with adherent pericarp; oblong; 0.8 mm long.

DISTRIBUTION South America: Brazil.

NOTES Eragrostideae. Renvoize 1996.

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