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.

Merostachys medullosa

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms arching; 1000–1500 cm long; 20 mm diam.; woody. Culm-internodes terete; with small lumen; light green and dark green; mottled; retrorsely scabrous. Culm-nodes swollen; pallid; bearded. Lateral branches dendroid. Branch complement many (12–54); flabellate. Culm-sheaths deciduous; 50–75 cm long; 10–15 times as long as wide; setose on shoulders; shoulders with 15 mm long hairs. Culm-sheath ligule 2–2.5 mm high. Culm-sheath blade linear; deciduous; reflexed; 13 cm long; 4 mm wide. Leaves 10–17 per branch. Leaf-sheaths tight; pubescent; outer margin hairy. Leaf-sheath oral hairs setose; 12–15 mm long; dark. Leaf-sheath auricles erect. Ligule a ciliolate membrane; 0.5 mm long. Collar with external ligule. Leaf-blade base asymmetrical; with a brief petiole-like connection to sheath; petiole glabrous. Leaf-blades lanceolate; 7–11.5 cm long; 16–20 mm wide. Leaf-blade margins scaberulous. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; unilateral; 5–10 cm long; 20 mm wide. Rhachis angular; pilose on surface; terminating in a sterile spikelet. Spikelet packing broadside to rhachis; contiguous.

Spikelets pectinate; solitary. Fertile spikelets pedicelled. Pedicels ciliate.

STERILE SPIKELETS Apical sterile spikelets rudimentary.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets elliptic; laterally compressed; 16 mm long; 4 mm wide; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; shorter than spikelet. Lower glume lanceolate; 6 mm long; chartaceous; without keels; 1 -veined. Lower glume primary vein ciliolate. Lower glume lateral veins absent. Lower glume margins ciliate. Lower glume apex setaceously attenuate. Upper glume ovate; 13 mm long; membranous; 7 -veined. Upper glume surface hispid. Upper glume margins ciliate. Upper glume apex acute; awned; 1 -awned. Upper glume awn 1 mm long.

FLORETS Fertile lemma ovate; 15 mm long; 8 mm wide; chartaceous; light brown; without keel; 17 -veined. Lemma lateral veins transversely connected at apex. Lemma surface scaberulous; rough below; puberulous. Lemma margins ciliate. Lemma hairs dark brown. Lemma apex acute. Palea 16 mm long. Palea keels ciliolate. Palea surface scaberulous (above); pilose; hairy at base. Rhachilla extension 16 mm long.

FLOWER Lodicules 3. Anthers 3; 9 mm long; purple. Stigmas 2.

FRUIT Caryopsis with free brittle pericarp.

DISTRIBUTION South America: Brazil.

NOTES Bambuseae. Sendulsky 2001.

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