Poaceae
Sclerodactylon

Sclerodactylon macrostachyum (Benth.) A.Camus

First published in Bull. Soc. Bot. France 79: 38 (1932)
This species is accepted
The native range of this species is E. Tanzania to NE. Mozambique, W. Indian Ocean, Andaman & Nicobar Islands. It is a perennial and grows primarily in the seasonally dry tropical biome.

Descriptions

Gramineae, T. Cope. Flora Zambesiaca 10:2. 1999

Morphology General Habit
Densely caespitose glaucous perennial, sometimes with creeping stolons; culms up to 50 cm tall, erect and straight, simple or rarely fasciculately branched from the lower nodes, the leaves all basal; leaf laminas 20–40 cm × up to 2.5 mm, subulate, cylindrical or ± compressed and elliptic in section, glabrous, pungent.
Morphology Reproductive morphology Inflorescences
Racemes 2–3, 5–10 cm long, rigid and straight.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets 7–15 mm long, 7–20-flowered, lanceolate or oblong to elliptic or ovate-elliptic; glumes obliquely lanceolate in profile, acute or subacute, the inferior 2–3 mm long, the superior 3–4 mm long; lemmas 4.5–5 mm long, obliquely ovate in profile, the lateral nerves obsolete below but prominent above.
[FZ]

Morphology General Habit
Perennial; caespitose. Stolons present. Culms erect; 40-60 cm long. Ligule a fringe of hairs. Leaf-blades terete; 10-30 cm long; 2-3 mm wide; stiff. Leaf-blade apex acuminate; pungent.
Morphology Reproductive morphology Inflorescences
Inflorescence composed of racemes. Racemes 2(-3); paired; unilateral; 7-12 cm long. Rhachis angular; terminating in a sterile spikelet. Spikelet packing broadside to rhachis; crowded; regular; 2 -rowed. Spikelets solitary. Fertile spikelets sessile.
Sterile
Apical sterile spikelets rudimentary.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets comprising 5-40 fertile florets; with diminished florets at the apex. Spikelets oblong, or ovate; laterally compressed; compressed strongly; 5-20 mm long; breaking up at maturity; disarticulating below each fertile floret, or below groups of fertile florets. Apical sterile spikelets rudimentary.
Fertile
Spikelets comprising 5-40 fertile florets; with diminished florets at the apex. Spikelets oblong, or ovate; laterally compressed; compressed strongly; 5-20 mm long; breaking up at maturity; disarticulating below each fertile floret, or below groups of fertile florets.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes persistent; similar; shorter than spikelet; similar to fertile lemma in texture. Lower glume ovate; 0.75 length of upper glume; coriaceous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 0.5 length of adjacent fertile lemma; coriaceous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex acute; muticous, or mucronate. Upper glume awn subapical.
Morphology Reproductive morphology Flowers Florets
Fertile lemma ovate; 2.5-3 mm long; coriaceous; 3 -veined. Lemma midvein scaberulous. Lemma lateral veins obscure. Lemma apex acute. Palea keels winged; conspicuously winged; scaberulous. Apical sterile florets resembling fertile though underdeveloped.
Morphology Reproductive morphology Flowers
Lodicules 2; cuneate; fleshy.
Morphology Reproductive morphology Fruits
Caryopsis with free soft pericarp; ellipsoid; laterally compressed; trigonous. Embryo 0.3 length of caryopsis.
Distribution
Africa: east tropical, southern tropical, and western Indian ocean.
Reference
Eragrostideae. WDC.
[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

  • Flora Zambesiaca

    • Flora Zambesiaca
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • 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

    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/

  • 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

  • Kew Science Photographs

    • Copyright applied to individual images