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 caucaiana

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms erect; pendulous at the tip; woody. Culm-internodes terete; hollow; mid-green and dark green; mottled. Culm-nodes bearded (retrorsely). Lateral branches dendroid. Branch complement many; flabellate; thinner than stem. Culm-sheaths deciduous. Leaves 4–5 per branch. Leaf-sheaths tight; glabrous on surface; outer margin glabrous, or hairy. Leaf-sheath oral hairs setose; 13–15 mm long. Ligule a ciliolate membrane; 0.5 mm long. Collar with external ligule. Leaf-blade base asymmetrical; with a brief petiole-like connection to sheath. Leaf-blades ovate; 2–7 cm long; 5–12 mm wide. Leaf-blade venation without cross veins. Leaf-blade surface glabrous; hairless except near base. Leaf-blade margins scaberulous. Leaf-blade apex acuminate.

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

Racemes 1; single; unilateral; 2–3 cm long. Rhachis pilose on surface; terminating in a sterile spikelet. Spikelet packing broadside to rhachis; contiguous; regular.

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

STERILE SPIKELETS Apical sterile spikelets rudimentary.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets, or 2 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 9–10 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; shorter than spikelet. Lower glume lanceolate; 2 mm long; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface puberulous. Lower glume margins ciliolate. Lower glume apex acuminate. Upper glume lanceolate; 7 mm long; chartaceous; 9–11 -veined. Upper glume surface puberulous. Upper glume margins ciliate. Upper glume apex acuminate.

FLORETS Fertile lemma elliptic; 7 mm long; 2–3 mm wide; chartaceous; without keel; 9 -veined. Lemma surface puberulous. Lemma margins ciliolate. Palea 7 mm long; 1 length of lemma; chartaceous. Palea keels contiguous above a sulcus; ciliolate. Palea surface puberulous; hairy on back. Rhachilla extension pubescent. Apical sterile florets 1 in number; rudimentary.

FLOWER Lodicules 3; 2 mm long; ciliate. Anthers 3. Stigmas 2.

FRUIT Caryopsis with free brittle pericarp; ellipsoid; 6 mm long; light brown; cuspidate.

DISTRIBUTION South America: Brazil.

NOTES Bambuseae. Sendulsky 2001.

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