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.

Hydrothauma manicatum

HABIT Annual. Culms decumbent, or prostrate; 10–20 cm long; spongy; rooting from lower nodes. Leaf-sheath auricles erect. Ligule an eciliate membrane; 1 mm long. Leaf-blade base with a false petiole. Leaf-blades floating; 5–10 cm long; 2–3 mm wide; flaccid. Leaf-blade surface ribbed; with ribs raised into sinuous lamellae. Leaf-blade apex obtuse.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; 3–6 cm long. Primary panicle branches accrescent to a central axis; with evident branchlets on axis. Panicle axis flat.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear; 1–2 mm long; tip discoid.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; gibbous; 1.8–2.5 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume oblate; 0.5 length of spikelet; hyaline; pallid; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex truncate. Upper glume elliptic; gibbous; membranous; without keels; 7–9 -veined. Upper glume apex entire, or with a unilateral tooth.

FLORETS Basal sterile florets male, or barren; with palea. Lemma of lower sterile floret similar to upper glume; oblong; 1 length of spikelet; membranous; 7 -veined; emarginate. Fertile lemma elliptic; 1–1.2 mm long; cartilaginous; dark brown; without keel. Lemma lateral veins obscure. Lemma margins flat. Lemma apex acute. Palea cartilaginous.

FLOWER Anthers 3; 0.8 mm long.

DISTRIBUTION Africa: west-central tropical and southern tropical.

NOTES Paniceae. FTEA.

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