Streptostachys rigidifolia

HABIT Perennial; caespitose. Rhizomes short. Culms erect; robust; 68–95 cm long. Culm-internodes terete; hollow; distally glabrous. Culm-nodes swollen; pubescent. Lateral branches lacking. Leaves basal and cauline. Leaf-sheaths striately veined; glabrous on surface, or pilose; outer margin hairy. Ligule a ciliate membrane; 1 mm long; pilose on abaxial surface. Leaf-blades lanceolate; 25–50 cm long; 5–8 mm wide; stiff. Leaf-blade surface glabrous, or pilose; sparsely hairy. Leaf-blade margins ciliate. Leaf-blade apex acuminate; pungent.

INFLORESCENCE Inflorescence composed of racemes. Peduncle 15–30 cm long; antrorsely scabrous above.

Racemes 2–6; digitate; 9–11 cm long.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels with the longest adnate below to rhachis; oblong; 1–3 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 5–8 mm long; falling entire. Spikelet callus incorporating lowest rhachilla internode with adnate lower glume; 0.5 mm long. Rhachilla internodes elongated between glumes and elongated below basal sterile floret. Rhachilla elongation stout.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma, or similar to fertile lemma in texture. Lower glume ovate; 3–6 mm long; 0.33–0.66 length of spikelet; membranous; without keels; 3(–5) -veined. Lower glume apex acute. Upper glume ovate; 5–6 mm long; 0.9–1 length of spikelet; coriaceous; without keels; 5 -veined. Upper glume lateral veins transversely connected at apex. Upper glume surface pubescent. Upper glume apex acute.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 5–6.5 mm long; 1 length of spikelet; coriaceous; 5 -veined; pilose; hairy above; acute. Palea of lower sterile floret hyaline; 4.5 mm long. Fertile lemma ovate; 4.5 mm long; 1.6 mm wide; indurate; pallid; shiny; without keel; 5 -veined. Lemma surface papillose. Lemma margins involute. Palea 1 length of lemma; indurate; without keels. Palea surface papillose.

FLOWER Lodicules 2; cuneate; 0.5–0.8 mm long; fleshy; truncate. Anthers 3; 3 mm long; purple.

FRUIT Caryopsis with adherent pericarp; ellipsoid; dorsally compressed; plano-convex; 3–3.5 mm long. Hilum linear; 1 length of caryopsis.

DISTRIBUTION South America: Brazil.

NOTES Paniceae. Filguiras et al 2001.

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