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.

Hygrochloa

HABIT Annual. Culms erect (1), or prostrate (1); 60–115–200 cm long; spongy (1), or firm (1); rooting from lower nodes (1/1). Lateral branches fastigiate (1/1). Ligule a fringe of hairs. Leaf-blade margins cartilaginous (1/1).

INFLORESCENCE Monoecious; with male and female spikelets in the same inflorescence. Inflorescence composed of racemes.

Racemes borne along a central axis; appressed; unilateral; bearing few fertile spikelets; bearing 1–4 fertile spikelets on each, or 5–10 fertile spikelets on each (1). Central inflorescence axis tip subulate. Rhachis angular; terminating in a barren extension; extension subulate. Spikelet packing abaxial.

Sexes segregated; on unisexual branches; with male above. Spikelets solitary. Fertile spikelets sessile. Male spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 2–2.312–2.75 mm long; falling entire.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate (1), or orbicular (1); membranous; without keels; 0 -veined (1), or 3 -veined (1). Lower glume lateral veins absent (1), or distinct (1). Lower glume surface without pits. Lower glume apex entire, or erose, or dentate; 2 -fid; truncate (1), or obtuse. Upper glume ovate; membranous; without keels; 5–7 -veined. Upper glume apex entire, or lobed (1); 2 -fid (1/1); obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret ovate; membranous; 5–7 -veined; acute. Fertile florets female. Fertile lemma ovate; coriaceous; much thinner on margins; without keel; wingless; 5 -veined. Lemma surface unwrinkled; without grooves. Lemma margins covering most of palea. Lemma apex acute. Palea 1 length of lemma; coriaceous; 2 -veined.

FLOWER Anthers 3.

FRUIT Caryopsis with adherent pericarp; obovoid; dorsally compressed. Embryo 0.66 length of caryopsis. Hilum punctiform.

MALE Male spikelets distinct from female; oblong. Male spikelet glumes 2.

DISTRIBUTION Australasia.

Please cite this publication as detailed in How to Cite Version: 27th January 2014.