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.

Merostachys petiolata

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms erect; pendulous at the tip; 700–800 cm long; 10–15 mm diam.; woody. Culm-internodes terete; hollow; retrorsely scabrous. Lateral branches dendroid. Branch complement many; flabellate; thinner than stem. Culm-sheaths deciduous. Culm-sheath blade lanceolate; reflexed. Leaf-sheaths transversely wrinkled; outer margin hairy. Leaf-sheath oral hairs setose; erect. Ligule a ciliolate membrane. Collar with external ligule. Leaf-blade base symmetrical; with a brief petiole-like connection to sheath; petiole glabrous. Leaf-blades linear, or lanceolate; 4–12 cm long; 6–9 mm wide. Leaf-blade venation without cross veins. Leaf-blade surface glabrous, or puberulous; hairy abaxially. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence composed of racemes; exserted, or embraced at base by subtending leaf.

Racemes 1; single; arcuate; unilateral; 2–10 cm long. Rhachis puberulous on surface; terminating in a sterile spikelet. Spikelet packing broadside to rhachis; contiguous; regular.

Spikelets pectinate; solitary. Fertile spikelets sessile.

STERILE SPIKELETS Apical sterile spikelets rudimentary.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; compressed slightly; 4–6 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes one the lower absent or obscure; persistent; shorter than spikelet. Upper glume ovate; 2–4 mm long; chartaceous. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea; persisting on inflorescence. Lemma of lower sterile floret ovate; 2–4 mm long; 5 -veined; acuminate. Fertile lemma oblong, or ovate; 4–6 mm long; chartaceous; without keel. Lemma surface pubescent. Lemma apex acuminate. Palea 1 length of lemma; chartaceous. Palea keels contiguous above a sulcus. Apical sterile florets 1 in number; rudimentary.

FLOWER Lodicules 3. Anthers 3. Stigmas 2.

FRUIT Caryopsis with free brittle pericarp.

DISTRIBUTION South America: Brazil.

NOTES Bambuseae. Fl Cat 1996.

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