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.

Oryza barthii

HABIT Annual; caespitose. Culms geniculately ascending, or decumbent; 60–120 cm long; spongy; 3–8 -noded; rooting from lower nodes. Leaf-sheaths smooth; glabrous on surface. Leaf-sheath auricles erect. Ligule an eciliate membrane; 2–6 mm long; truncate, or obtuse. Leaf-blades 15–45 cm long; 4–13 mm wide. Leaf-blade surface scaberulous; rough adaxially. Leaf-blade margins scabrous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle.

Panicle open; obovate; 20–35 cm long; 3–7.5 cm wide. Primary panicle branches appressed, or ascending. Panicle branches angular; scaberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear; angular; 1–6 mm long; smooth, or scaberulous; tip cupuliform; bibracteate.

FERTILE SPIKELETS Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 7–11 mm long; 2.5–3.4 mm wide; falling entire. Spikelet callus glabrous; base truncate; attached obliquely.

GLUMES Glumes both absent or obscure.

FLORETS Basal sterile florets similar; barren; without significant palea. Lemma of lower sterile floret lanceolate; 2.5–4.5 mm long; 0.3–0.4 length of spikelet; membranous; 1 -veined; without lateral veins; smooth, or scaberulous; acute. Lemma of upper sterile floret lanceolate; 2.5–4.5 mm long; 1 length of lower sterile floret; membranous. Fertile lemma elliptic; laterally compressed; 7–11 mm long; coriaceous; keeled; 5 -veined. Lemma midvein ciliate; hairy above. Lemma surface reticulate; glabrous, or hispid. Lemma margins involute. Lemma apex rostrate; awned; 1 -awned. Principal lemma awn (65–)80–160(–190) mm long overall (pink); limb scabrous. Palea elliptic; 1 length of lemma; coriaceous; 3 -veined; 1-keeled. Palea keels scabrous. Palea apex acute.

FLOWER Lodicules 2; lanceolate; membranous. Anthers 6. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Disseminule comprising a floret.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, and south.

NOTES Oryzeae. FZ.

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