Poaceae
Cynosurus

Cynosurus polybracteatus Poir.

First published in Voy. Barbarie 2: 97 (1798)
This species is accepted
The native range of this species is Algeria to Tunisia. It is an annual and grows primarily in the subtropical biome.

Descriptions

Morphology General Habit
Annual; culms solitary, or caespitose. Culms erect, or geniculately ascending; 10-80 cm long. Culm-internodes striate; smooth; distally glabrous. Culm-nodes brown. Leaf-sheaths without keel; striately veined; smooth; glabrous on surface. Ligule an eciliate membrane; 1.5 mm long; lacerate; truncate. Leaf-blades 7-15 cm long; 1-3.5 mm wide. Leaf-blade surface smooth, or scaberulous; rough abaxially; pubescent; hairy adaxially. Leaf-blade margins scabrous. Leaf-blade apex abruptly acute, or acute; callose.
Morphology Reproductive morphology Inflorescences
Inflorescence a panicle. Panicle spiciform; linear; secund; 1.5-9 cm long; 0.3-0.6 cm wide. Panicle axis angular; pubescent. Panicle branches scabrous. Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets sessile; 1 in the cluster.
Morphology Reproductive morphology Inflorescences Spikelets
Companion sterile spikelets well-developed; containing empty lemmas; cuneate; laterally compressed; 4 mm long; as long as fertile; persistent. Companion sterile spikelet glumes herbaceous; 3.5-4 mm long; keeled; winged on keels; 1 -veined; scabrous (on keel); mucronate (mucro 0.2-0.5mm). Companion sterile spikelet lemmas 6-10; exserted from glumes; 3.5-4 mm long (linear); muticous (mucronate). Spikelets comprising 3-5 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 4 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes glabrous.
Sterile
Companion sterile spikelets well-developed; containing empty lemmas; cuneate; laterally compressed; 4 mm long; as long as fertile; persistent. Companion sterile spikelet glumes herbaceous; 3.5-4 mm long; keeled; winged on keels; 1 -veined; scabrous (on keel); mucronate (mucro 0.2-0.5mm). Companion sterile spikelet lemmas 6-10; exserted from glumes; 3.5-4 mm long (linear); muticous (mucronate).
Fertile
Spikelets comprising 3-5 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 4 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes glabrous.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; similar; reaching apex of florets, or exceeding apex of florets. Lower glume lanceolate; 3.5 mm long; 1 length of upper glume; chartaceous; much thinner on margins; 1-keeled; 1 -veined. Lower glume primary vein smooth, or scaberulous. Lower glume lateral veins absent. Lower glume apex acuminate; mucronate. Upper glume lanceolate; 4 mm long; chartaceous; with hyaline margins; 1-keeled; 1 -veined. Upper glume primary vein smooth, or scaberulous. Upper glume lateral veins absent. Upper glume apex acuminate; mucronate.
Morphology Reproductive morphology Flowers Florets
Fertile lemma oblong; 2.5-2.8 mm long; chartaceous; without keel; 5 -veined. Lemma surface scabrous. Lemma apex emarginate, or obtuse; muticous. Palea lanceolate; 1 length of lemma. Palea keels scabrous. Palea surface scaberulous. Palea apex obtuse.
Morphology Reproductive morphology Flowers
Lodicules 2; ovate; 0.5 mm long; membranous; acute. Anthers 3; 1.5 mm long.
Morphology Reproductive morphology Fruits
Caryopsis with adherent pericarp; oblong; dorsally compressed; 1.6-1.8 mm long; dark brown; glabrous. Embryo 0.25 length of caryopsis. Hilum elliptic; 0.2 length of caryopsis.
Distribution
Africa: north.
Reference
Poeae. Fl Afr Nord 1999.
[GB]

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]

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

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2026. 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 2026. 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