Poaceae
Guadua

Guadua chacoensis (Rojas Acosta) Londoño & P.M.Peterson

First published in Novon 2: 41 (1992)
This species is accepted
The native range of this species is Bolivia to S. Brazil and N. Argentina. It is a bamboo and grows primarily in the seasonally dry tropical biome.

Descriptions

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Morphology General Habit
Perennial; caespitose. Rhizomes short; pachymorph. Culms erect; inclined at the tip; 1000-2000 cm long; 8-15 mm diam.; woody; with root thorns from the nodes. Culm-internodes semiterete; thin-walled; mid-green. Lateral branches dendroid; intravaginal. Bud complement 1. Branch complement three, or several; thinner than stem. Culm-sheaths deciduous; 20-50 cm long; 1.7-2.5 times as long as wide; glabrous, or hispid; with tawny hairs; truncate at apex; without auricles; glabrous on shoulders. Culm-sheath ligule 0.8-1 mm high; ciliolate. Culm-sheath blade triangular; as wide as sheath at base; demarcated but persistent; erect; 4-13 cm long; 30-80 mm wide; glabrous on surface, or pubescent and with ciliate margins; acute. Leaves 7-9 per branch. Leaf-sheaths glabrous on surface; outer margin hairy. Leaf-sheath oral hairs ciliate; curly; 2-3 mm long; pale. Ligule a ciliolate membrane; 0.2-0.4 mm long; pubescent on abaxial surface. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.2-0.3 cm long; petiole glabrous. Leaf-blades lanceolate; 10-24 cm long; 5-25 mm wide. Leaf-blade venation with 8-14 secondary veins. Leaf-blade surface glabrous, or hispid; sparsely hairy; hairy adaxially. Leaf-blade margins scabrous. Leaf-blade apex acuminate.
Morphology Reproductive morphology Inflorescences
Synflorescence bractiferous; paniculate; 30-40 cm long; open; with glumaceous subtending bracts; bracts 8-10 mm long; with axillary buds at base of spikelet; prophyllate below lateral spikelets. Fertile spikelets sessile.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 1-2 basal sterile florets; 2-4 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 20-50 mm long; 4-5 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 5-7 mm long; obscured by lemmas; pubescent.
Fertile
Spikelets comprising 1-2 basal sterile florets; 2-4 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 20-50 mm long; 4-5 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 5-7 mm long; obscured by lemmas; pubescent.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes several; 1-2 empty glumes; persistent; similar; shorter than spikelet. Upper glume ovate; 5-8 mm long; without keels; 7-9 -veined. Upper glume apex acute; mucronate.
Morphology Reproductive morphology Flowers Florets
Basal sterile florets similar; barren; without significant palea; persisting on inflorescence. Lemma of lower sterile floret similar to upper glume; ovate; 10-14 mm long; puberulous; obtuse; mucronate. Fertile lemma ovate; 12-16 mm long; 7-12 mm wide; coriaceous; shiny; without keel; 12-17 -veined. Lemma surface puberulous; hairy below. Lemma margins convolute; covering most of palea. Lemma apex obtuse; mucronate, or awned. Principal lemma awn 0.8-1 mm long overall. Palea 6-14 mm long; 11 -veined. Palea keels winged; conspicuously winged. Palea surface pubescent. Apical sterile florets resembling fertile though underdeveloped.
Morphology Reproductive morphology Flowers
Lodicules 3; 3-5 mm long; veined; ciliate. Anthers 6; 5-8 mm long; anther tip apiculate. Stigmas 3.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; fusiform; 9-12 mm long; light brown. Embryo 0.5 length of caryopsis.
Distribution
South America: western South America, Brazil, and southern South America.
Reference
Bambuseae. Lond & Pet 1996.
[GB]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0

  • GrassBase - The Online World Grass Flora

    • Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). GrassBase - The Online World Grass Flora.
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Herbarium Catalogue Specimens

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0