GrassBase - The Online World Grass Flora


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

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

Pentameris insularis

HABIT Perennial; cushion forming. Stolons present. Butt sheaths pallid; glossy; glabrous; persistent and investing base of culm. Glands absent. Culms 35–45 cm long; 10 -noded. Lateral branches sparse. Leaves mostly basal. Leaf-sheaths glabrous on surface. Leaf-sheath oral hairs lacking. Ligule a fringe of hairs. Leaf-blades 8 cm long; 4 mm wide; stiff; eglandular. Leaf-blade surface glabrous. Leaf-blade margins scabrous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle; comprising 30–50 fertile spikelets.

Panicle open; ovate; 3.5–7 cm long; 2–4 cm wide. Panicle branches eglandular; glabrous in axils.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; 0.8 length of fertile spikelet; eglandular; scaberulous.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; without rhachilla extension. Spikelets cuneate; laterally compressed; 6.5–7.5 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; 6.5–7.5 mm long; 1 length of upper glume; membranous; yellow; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume elliptic; 6.5–7.5 mm long; 2.6 length of adjacent fertile lemma; membranous; yellow; 1-keeled; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent. Upper glume apex acuminate.

FLORETS Fertile lemma oblong; 2.5–2.8 mm long; membranous; without keel; 5–9 -veined. Lemma surface villous; hairy at base. Lemma apex lobed; 2 -fid; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 7.5–12 mm long overall; with twisted column. Lateral lemma awns arising on inner edge of lobes; 2–2.5 mm long; enclosed by glumes; shorter than principal. Palea surface glabrous.

FLOWER Lodicules 2; cuneate; fleshy; glabrous. Anthers 3; 1.3 mm long; yellow.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Antarctic: Subantarctic islands.

NOTES Arundineae. Linder 1992.

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