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.

Oryza longistaminata

HABIT Perennial. Rhizomes elongated. Culms geniculately ascending, or decumbent; 70–120 cm long; 5–10 mm diam.; spongy; (2–)4–10 -noded; rooting from lower nodes. Leaf-sheaths smooth; glabrous on surface. Leaf-sheath auricles erect; 10–15 mm long. Ligule an eciliate membrane; 15–45 mm long; entire, or lacerate; acute. Leaf-blades 10–75 cm long; 5–25 mm wide. Leaf-blade midrib indistinct, or evident. Leaf-blade surface scaberulous; rough adaxially. Leaf-blade margins scabrous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic, or oblong; 16–40 cm long; 1.5–8 cm wide. Primary panicle branches appressed, or ascending. Panicle branches angular; scaberulous; glabrous in axils, or pubescent in axils.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear; angular; 0.5–4(–7) 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; 7–12 mm long; 2–3 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–)2.5–3.8(–4.5) mm long; 0.3–0.4 length of spikelet; membranous; 1 -veined; without lateral veins; acute, or acuminate. Lemma of upper sterile floret lanceolate; (2–)2.5–3.8(–4.5) mm long; 1 length of lower sterile floret; membranous. Fertile lemma elliptic; laterally compressed; 7–12 mm long; coriaceous; keeled; 5 -veined. Lemma midvein spinulose. Lemma surface reticulate; hispid. Lemma margins involute. Lemma apex rostrate; awned; 1 -awned. Principal lemma awn (26–)40–75 mm long overall; limb scabrous. Palea elliptic; 0.9 length of lemma; coriaceous; 3 -veined; 1-keeled. Palea keels scabrous. Palea apex acute.

FLOWER Lodicules 2; lanceolate; membranous. Anthers 6; 4.5–5.5 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 7.5–8.5 mm long. Disseminule comprising a floret.

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

NOTES Oryzeae. FZ.

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