Enhalus Rich.

This genus is accepted, and its native range is Somalia to N. Mozambique, SW. Arabian Peninsula, Indian Ocean to W. Pacific.

[FSOM]

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

Morphology General Habit
Dioecious perennials with creeping, coarse, not or sparsely branched rhizomes
Vegetative Multiplication Rhizomes
Rhizome dorsiventral with distichously arranged leaves
Morphology Stem
Internodes very short, obscured by the persistent fibrous remains of leaf sheaths
Morphology Roots
Roots unbranched, numerous
Morphology Leaves
Leaves strap-shaped, with an open sheathing base and with many parallel nerves
Morphology Reproductive morphology Flowers
Male inflorescences shortly pedunculate, initially enclosed by two fused bracts; flowers numerous, small, pedicellate, breaking off just before anthesis and floating on the surface with the tepals reflexed; tepals 6; stamens 3; anthers subsessile, latrorsely dehiscent; pollen grains globose, very large
Morphology Reproductive morphology Inflorescences
Female inflorescence 1-flowered on a long peduncle, enclosed by two overlapping, scarcely fused, strongly keeled bracts, distinctly hairy on the keel; outer tepals 3, green, recurved; inner tepals 3, white, linear-oblong, erect, papillose; ovary of 6 carpels, with several ovules; styles 6, each with 2 long stigmatic branches; flowers floating on the surface at maturity and drawn beneath the water surface after pollination
Morphology Reproductive morphology Fruits
Fruit fleshy, softly spiny, dehiscing by decay of the pericarp; seeds few, obconical, angular.
Note
Genus with a single species.

[FTEA]

Hydrocharitaceae, David Simpson. Flora of Tropical East Africa. 1989

Morphology General Habit
Dioecious, submerged, marine, perennial herbs
Morphology Roots
Roots coarse, simple
Morphology Stem
Stem elongate, rhizomatous, rarely branched, with very short internodes
Morphology Leaves Stipules
Stipules 0
Morphology Leaves
Nodal scales 0 Leaves sessile, usually 2–6, distichously arranged at the end of the rhizome, linear, falcate, rounded or obtuse, distinctly sheathing at the base, opaque or somewhat translucent, with numerous longitudinal veins and septate air channels; margins green, entire or serrulate near the apex in young leaf
Morphology Reproductive morphology Flowers
Flowers unisexual Male flowers shortly pedicellate, breaking free and floating before anthesis; sepals 3, oblong, acute, reflexed at anthesis; petals 3, ovate, acute, papillose, reflexed at anthesis; stamens 3; anthers subsessile, linear, erect, 1-thecous, latrorsely dehiscent. Female spathe solitary in the leaf-axil, long-pedunculate, the peduncle spirally contracted after fertilisation, 1-flowered, composed of 2, ± free bracts, the bracts oblong-lanceolate, obtuse, strongly keeled and distinctly hairy on the keel, translucent Female flower: sepals 3, oblong, acute, strongly recurved; petals 3, linear-oblong, acute, erect, papillose; staminodes 0; ovary of 6 carpels, narrowly cylindric, densely hairy, 1-locular, placentation parietal; perianth-tube absent; styles 6, reduced; stigmas 6, subulate, densely papillose except at the apex
Morphology Reproductive morphology Inflorescences
Male spathe solitary in the leaf-axil, pedunculate, with numerous flowers, composed of 2 partly connate bracts, the bracts ovate-lanceolate, obtuse, slightly keeled and distinctly hairy on the keel, translucent
sex Male
Male spathe solitary in the leaf-axil, pedunculate, with numerous flowers, composed of 2 partly connate bracts, the bracts ovate-lanceolate, obtuse, slightly keeled and distinctly hairy on the keel, translucent Male flowers shortly pedicellate, breaking free and floating before anthesis; sepals 3, oblong, acute, reflexed at anthesis; petals 3, ovate, acute, papillose, reflexed at anthesis; stamens 3; anthers subsessile, linear, erect, 1-thecous, latrorsely dehiscent.
sex Female
Female spathe solitary in the leaf-axil, long-pedunculate, the peduncle spirally contracted after fertilisation, 1-flowered, composed of 2, ± free bracts, the bracts oblong-lanceolate, obtuse, strongly keeled and distinctly hairy on the keel, translucent Female flower: sepals 3, oblong, acute, strongly recurved; petals 3, linear-oblong, acute, erect, papillose; staminodes 0; ovary of 6 carpels, narrowly cylindric, densely hairy, 1-locular, placentation parietal; perianth-tube absent; styles 6, reduced; stigmas 6, subulate, densely papillose except at the apex
Morphology Reproductive morphology Fruits
Fruit ovoid to subglobose, acuminate, ribbed, densely hairy, opening by decay of the pericarp
Morphology Reproductive morphology Seeds
Seeds obconical, angular.

Native to:

Andaman Is., Bismarck Archipelago, Borneo, Cambodia, Caroline Is., Hainan, India, Jawa, Kenya, Lesser Sunda Is., Madagascar, Malaya, Maldives, Maluku, Marianas, Mozambique, Myanmar, Nansei-shoto, New Caledonia, New Guinea, Nicobar Is., Northern Territory, Philippines, Queensland, Saudi Arabia, Seychelles, Solomon Is., Somalia, South China Sea, Sri Lanka, Sulawesi, Sumatera, Tanzania, Thailand, Vietnam, Western Australia, Yemen

Enhalus Rich. appears in other Kew resources:

First published in Mém. Cl. Sci. Math. Inst. Natl. France 12(2): 64 (1811 publ. 1814)

Accepted by

  • Govaerts, R.H.A. (2011). World checklist of selected plant families published update Facilitated by the Trustees of the Royal Botanic Gardens, Kew.

Literature

Flora of Somalia

  • Flora Somalia, Vol 4, (1995) Author: by G. Sartoni [updated by M. Thulin 2008]

Flora of Tropical East Africa

  • G.P. 3: 454 (1883)
  • Hartog, Sea Grasses of the World: 214 (1970)
  • in Mém. Cl. Sci. Math. Phys. Inst. France, 1811(2): 64, 71, 74 (1812, published 1814)

  • 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 Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0