Cymodoceaceae

Cymodocea K.D.Koenig

First published in Ann. Bot. (König & Sims) 2: 96 (1806)
This genus is accepted
The native range of this genus is Coasts of Tropical & Subtropical Old World to W. Pacific.

Descriptions

J. R. Timberlake, E. S. Martins (2009). Flora Zambesiaca, Vol 12 (part 2). Royal Botanic Gardens, Kew

Morphology General Habit
Marine herbs, rhizome monopodial, with 1–5 ± branched roots and a short erect stem with 2–7 leaf at each node; internodes 1–6 cm long
Morphology Leaves
Leaf sheath compressed, 1.5–10 cm long, persisting longer than leaf blade, leaving an open or closed circular scar when shed; ligule up to 1 mm long Leaf blade linear, up to 30 cm long, leaf apex obtuse or sometimes emarginate, ± serrulate or denticulate; veins 7–17, joined at apex by a marginal commissure
Morphology General Scales
Scales variable in number (up to 10) in two groups at each node Scales ovate
Morphology Reproductive morphology Flowers
Flowers solitary and terminal, subtended by a leaf similar to the others; an axillary bud at the penultimate leaf develops into a prolongation of the main axis giving rise to a sympodium
sex Male
Male flowers with a stalk elongating considerably at anthesis, the 2 anther united dorsally and attached at the same height
sex Female
Female flowers sessile or shortly stalked; each ovary with a short style divided into 2 slender stigma
Morphology Reproductive morphology Fruits
Fruit with a stony pericarp, semi-circular to semi-ovate or elliptic, laterally compressed, with dorsal ridges and a beak.
Distribution
A genus of 4 species with a wide but disjunct distribution in tropical and subtropical seas (Cymodocea serrulata and . rotundata in the Indo-Pacific, . nodosa in the Mediterranean extending to S Portugal and the E Atlantic as far south as the Canary Islands and Mauritania, and C. angustata in NW and W coasts of Australia).
[FZ]

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Vegetative Multiplication Rhizomes
Rhizome herbaceous, monopodial, bearing at each node 1–2(–3) branched roots and distichously arranged foliage leaves, some leaves subtending a short leafy shoot; internodes 1–6 cm long
Morphology Leaves
Leaf sheath compressed, persisting longer than the leaf blade, when shed leaving an open or closed circular scar; blade flat, often narrowed at the base, up to 30 cm long, with 7–17 veins joined at the apex by a marginal commissure; apex rounded, obtuse or sometimes emarginate, with either microscopic marginal outgrowths or conspicuous marginal teeth
Morphology Reproductive morphology Flowers
Female flower terminal, sessile or shortly stalked; carpels each with a style divided into 2 slender stigmas up to 3 cm long Male flower stalked; anthers dorsally united and attached at the same level, each with a short apical process Flowers solitary, terminal on short erect shoots
Morphology Reproductive morphology Fruits
Fruit with a stony pericarp, laterally compressed, semicircular or semiovate in outline with dorsal ridges.
Distribution
Genus of three species with a wide but disjunct distribution. Two species are widely distributed in the tropical and subtropical Indian and western Pacific Oceans.
[FSOM]

Cymodoceaceae, Henk Beentje. Flora of Tropical East Africa. 2002

Morphology General Habit
Submerse aquatic herbs
Vegetative Multiplication Rhizomes
Rhizome creeping, monopodial, with many vascular bundles; each node with 1– 5 branched roots and a short erect stem bearing 2– 7 leaves; scales ovate, scarious
Morphology Leaves
Leaves with the sheath compressed, bi-auriculate, ligulate, persisting longer than the blade, leaving a scar when shed and giving the stem an annular appearance; blade linear, margins entire but for the distal part which becomes serrulate or spinulose, apex ± toothed; nerves 7– 17, with perpendicular cross-veins
Morphology Reproductive morphology Flowers
Flowers solitary and terminal, enclosed in a leaf similar to others, a bud in the axil of the penultimate leaf lengthening to give rise to a sympodium Staminate flowers stalked, of 2 dorsally connate anthers, attached at the same height, each crowned by subulate tip Pistillate flowers sessile or shortly stalked, of 2 free ovaries each with a short style, distally bifid
sex Male
Staminate flowers stalked, of 2 dorsally connate anthers, attached at the same height, each crowned by subulate tip
sex Female
Pistillate flowers sessile or shortly stalked, of 2 free ovaries each with a short style, distally bifid
Morphology Reproductive morphology Fruits
Fruit with stony pericarp, laterally compressed, semi-circular to elliptic in outline, with dorsal ridges and a beak.
[FTEA]

Sources

  • Flora Zambesiaca

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

  • Flora of Somalia

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

  • Flora of Tropical East Africa

    • Flora of Tropical East Africa
    • http://creativecommons.org/licenses/by-nc-sa/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