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.

Pogonarthria refracta

HABIT Perennial; caespitose. Culms geniculately ascending; 15–45 cm long; 3–5 -noded. Culm-internodes distally pilose. Leaf-sheaths glabrous on surface, or pilose. Leaf-sheath oral hairs bearded. Ligule a fringe of hairs. Leaf-blades flat, or involute; (1.5–)3–15(–20) cm long; 1.5–2.5 mm wide. Leaf-blade surface pilose; hairy on both sides. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes; bearing juvenile spikelets at emergence.

Racemes numerous; borne along a central axis; deflexed, or spreading; unilateral; 0.8–1.5 cm long. Central inflorescence axis 4–15 cm long. Rhachis deciduous from axis; angular; scabrous on margins. Spikelet packing broadside to rhachis; crowded.

Spikelets ascending; solitary. Fertile spikelets pedicelled. Pedicels cuneate; 0.8–2 mm long; scaberulous.

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 4–6 mm long; breaking up at maturity; disarticulating between fertile florets but the lowest falling with glumes attached. Rhachilla internodes elongated below proximal fertile floret; clavate; 0.8 mm long; pubescent; hairy at tip.

GLUMES Glumes deciduous with pedicel attached (to rhachis); similar; shorter than spikelet. Lower glume lanceolate; 1.5–1.7 mm long; 1–1.1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scaberulous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 1.4–1.6 mm long; 0.6 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 florets decreasing in size upwards. Fertile lemma ovate; 2.5–3 mm long; membranous; keeled; 3 -veined. Lemma midvein scaberulous. Lemma margins ciliolate; hairy above. Lemma apex acuminate. Palea elliptic; 0.9 length of lemma; 2 -veined. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 0.6 mm long.

FRUIT Caryopsis with adherent pericarp; lanceolate; isodiametric; trigonous; 1.6 mm long.

DISTRIBUTION Africa: southern tropical.

NOTES Eragrostideae. WDC.

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