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.

Bothriochloa macra

HABIT Perennial; caespitose. Culms geniculately ascending; 30–100 cm long; 2–8 -noded. Culm-internodes channelled. Culm-nodes glabrous, or pubescent. Lateral branches ample. Leaf-sheaths loose; keeled; glabrous on surface. Ligule a ciliolate membrane; 1.5–2.5 mm long; truncate. Leaf-blades flat, or revolute; 5–30 cm long; 2.5–5.5 mm wide. Leaf-blade surface scaberulous; rough adaxially; pilose; sparsely hairy. Leaf-blade margins scaberulous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 3–6; digitate; 5–10 cm long. Rhachis fragile at the nodes; flattened; villous on margins. Rhachis hairs 4.5 mm long. Rhachis internodes linear; 4–4.5 mm long. Rhachis internode tip transverse.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; flattened; 4–4.5 mm long; with a translucent median line (also present in internodes); villous; with 4.5 mm long hairs.

STERILE SPIKELETS Companion sterile spikelets well-developed; comprising 2 unequal glumes without lemmas; lanceolate; 4.5–6 mm long; shorter than fertile. Companion sterile spikelet glumes without depressions; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear, or lanceolate; dorsally compressed; obtuse; 5–7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base obtuse; attached transversely. Spikelet callus hairs 0.5–1 mm long.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; coriaceous; without keels; keel-less except near apex. Lower glume primary vein scaberulous. Lower glume surface flat; without pits, or pitted; glabrous, or pilose; hairy below. Upper glume lanceolate; 1-keeled. Upper glume primary vein scabrous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 0.75 length of spikelet; hyaline. Fertile lemma linear; hyaline; without keel. Lemma apex entire; awned; 1 -awned. Principal lemma awn apical; geniculate; 20–23 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3.

DISTRIBUTION Australasia: Australia and New Zealand.

NOTES Andropogoneae. Fl NSW 1993.

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