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.

Humbertochloa bambusiuscula

HABIT Perennial; caespitose. Culms decumbent; 50–80 cm long. Culm-internodes retrorsely scabrous; distally glabrous, or pubescent. Ligule a ciliolate membrane. Leaf-blade base cordate; with a brief petiole-like connection to sheath. Leaf-blades ovate; 2–5 cm long; 14–18 mm wide. Leaf-blade venation with obscure cross veins. Leaf-blade margins ciliate. Leaf-blade apex acute.

INFLORESCENCE Monoecious; with male and female spikelets in different inflorescences. Inflorescence composed of racemes.

Racemes 4–6; borne along a central axis; in a unilateral false spike; appressed; lanceolate; 0.3–0.4 cm long; bearing 1 spikelet. Central inflorescence axis 1.5–3.3 cm long; foliaceous (3–4 mm wide); tip subulate. Rhachis deciduous from axis; broadly winged; terminating in a barren extension; extension flattened.

Spikelets solitary. Fertile spikelets sessile.

STERILE SPIKELETS Apical sterile spikelets absent, or rudimentary; 0–2 in number.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; compressed slightly; gibbous; 8–9 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume subulate; 0.15 length of spikelet. Upper glume oblong; 0.33 length of adjacent fertile lemma; membranous; without keels; 5–7 -veined. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 1 length of spikelet; coriaceous; 13–17 -veined; without grooves; obtuse. Fertile florets female. Fertile lemma ovate; 9 mm long; chartaceous; 7–11 -veined. Lemma margins involute. Lemma apex acuminate. Palea chartaceous; 2 -veined. Rhachilla extension 0.3 length of fertile floret.

FLOWER Lodicules 2. Anthers 4–5.

MALE Male inflorescence terminal; similar to female; of racemes along a central axis. Male spikelets similar to female but less developed; 3.5–4 mm long. Male spikelet glumes 2.

DISTRIBUTION Africa: western Indian ocean.

NOTES Phyllorachideae. FTEA.

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