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.

Pentameris rosea

HABIT Perennial; short-lived; cushion forming, or caespitose. Butt sheaths light brown; glabrous. Glands elongated. Culms decumbent; 150–400 cm long; 3–100 -noded. Lateral branches lacking, or sparse, or ample. Leaves basal and cauline. Leaf-sheaths glabrous on surface, or hirsute. Leaf-sheath oral hairs lacking, or ciliate. Ligule a fringe of hairs. Leaf-blades 50–100 cm long; 1–5 mm wide; firm, or flaccid. Leaf-blade surface glabrous, or hirsute; hairy abaxially. Leaf-blade margins glandular; smooth. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle; comprising 5–30 fertile spikelets.

Panicle open; ovate; 2–6 cm long; 1–6 cm wide. Panicle branches bearded in axils.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; 0.75–1 length of fertile spikelet; glandular; smooth, or scaberulous.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; without rhachilla extension. Spikelets cuneate; laterally compressed; 8–12 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; gaping. Lower glume elliptic; 8–12 mm long; 1 length of upper glume; membranous; yellow; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface asperulous; pilose; with tubercle-based hairs. Lower glume apex acuminate. Upper glume elliptic; 8–12 mm long; 3–3.5 length of adjacent fertile lemma; membranous; yellow; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume surface asperulous; pilose; with tubercle-based hairs. Upper glume apex acuminate.

FLORETS Fertile lemma oblong; 2.5–3.5 mm long; membranous; without keel; 5–9 -veined. Lemma surface villous. Lemma apex lobed; 2 -fid; with lobes 0.6–1 mm long; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 10–17 mm long overall; with twisted column. Lateral lemma awns arising on inner edge of lobes; 6–9 mm long; equalling glumes, or enclosed by glumes; shorter than principal. Palea surface pubescent; hairy above.

FLOWER Lodicules 2; cuneate; fleshy; glabrous. Anthers 3; 2.5–4 mm long; yellow, or purple.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Africa: south.

NOTES Arundineae. Linder.

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