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.

Arthropogon sorengii

HABIT Perennial; caespitose. Cataphylls evident. Rhizomes short; knotty. Butt sheaths thickened and forming a bulb. Culms erect; 30–40 cm long. Culm-nodes brown; glabrous. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths 8.5 cm long. Ligule a ciliolate membrane; 0.2–0.4 mm long; brown. Leaf-blades filiform; involute; 20–38 cm long; 1 mm wide; stiff. Leaf-blade surface ribbed; scaberulous (above), or papillose (below); glabrous. Leaf-blade apex abruptly acute.

INFLORESCENCE Inflorescence a panicle. Peduncle 7–13 cm long.

Panicle open; lanceolate; 5–8 cm long; 1.6–2.1 cm wide. Panicle branches capillary; flexuous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; terete; unequal; 2–22 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or oblong; laterally compressed; 4.5–5.5 mm long; falling entire. Spikelet callus pubescent, or pilose. Spikelet callus hairs 0.8–1.3(–2.8) mm long.

GLUMES Glumes dissimilar; shorter than spikelet; firmer than fertile lemma. Lower glume linear, or lanceolate; 1–3 mm long; 0.2–0.6 length of spikelet; coriaceous; without keels; 3 -veined. Lower glume apex awned; 1 -awned. Lower glume awn (4–)4.5–5.8(–6.8) mm long. Upper glume linear, or lanceolate; 5 mm long; 1 length of spikelet; coriaceous; with scarious margins; without keels; 3 -veined. Upper glume primary vein conspicuous. Upper glume surface scabrous; rough on veins. Upper glume awned; 1 -awned. Upper glume awn (2–)2.6–6 mm long.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; lanceolate; 4.5–5.5 mm long; 1 length of spikelet; membranous; 3 -veined; scabrous; rough on veins; erose; acute. Palea of lower sterile floret hyaline; 2.8–3 mm long. Fertile lemma lanceolate; 4.5–4.8 mm long; 1.1 mm wide; scarious; without keel; 3 -veined. Palea lanceolate; 3.9–4.1 mm long; 0.9 length of lemma; hyaline; 3 -veined; without keels.

FLOWER Lodicules 2; 0.2 mm long; fleshy. Anthers 3; 2.5–2.7 mm long; brown.

DISTRIBUTION South America: western South America.

NOTES Paniceae. Gir.-Canas 2012.

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