1. Family: Hydrocharitaceae Juss.
    1. Thalassia Banks & Sol. ex K.D.Koenig

      1. This genus is accepted, and its native range is Tropical & Subtropical coasts.

    [FTEA]

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

    Habit
    Dioecious, submerged, marine, perennial herbs
    Stem
    Stem elongate, rhizomatous or shortly erect, the latter produced at regular intervals from nodes along the rhizome
    Roots
    Roots 1 per node where erect stems produced from the rhizome, simple, sand-binding, covered with fine hairs
    Leaves
    Leaves sessile, usually 2–6, distichously arranged on the erect stems, linear, somewhat falcate, rounded or obtuse, distinctly sheathing at the base, opaque or somewhat translucent, with up to 19 longitudinal veins and numerous fine, longitudinal air channels, the longitudinal veins connected by cross-veins; margins green, entire Nodal scales 0
    Stipules
    Stipules 0
    Flowers
    Flowers unisexual Female flowers almost sessile; tepals 3, similar to the those of ♂; staminodes 0; ovary of 6–8 carpels, conical, muricate, 1(–3)-locular, placentation parietal; ovules several; perianth-tube narrowly cylindric; styles 6–8; stigmas 6–8, deeply 2-lobed, filiform, papillose Male flowers shortly pedicellate, remaining attached to the plant; tepals 3, elliptic, cucullate, strongly recurved at anthesis; stamens 3–12; anthers nearly sessile, oblong, erect, 2–4-thecous, latrorsely dehiscent
    Male
    Male spathes 1–2 in the leaf-axil, pedunculate, 1-flowered, composed of 2 bracts connate on one side only, the bracts oblong to lanceolate, acute to obtuse, entire or serrulate, translucent Male flowers shortly pedicellate, remaining attached to the plant; tepals 3, elliptic, cucullate, strongly recurved at anthesis; stamens 3–12; anthers nearly sessile, oblong, erect, 2–4-thecous, latrorsely dehiscent
    Inflorescences
    Female spathe solitary in the leaf-axil, pedunculate, 1-flowered, composed of 2 connate bracts, cylindric, but tapering at both ends, translucent, 2-lobed at the apex, the lobes acute to obtuse Male spathes 1–2 in the leaf-axil, pedunculate, 1-flowered, composed of 2 bracts connate on one side only, the bracts oblong to lanceolate, acute to obtuse, entire or serrulate, translucent
    Female
    Female flowers almost sessile; tepals 3, similar to the those of ♂; staminodes 0; ovary of 6–8 carpels, conical, muricate, 1(–3)-locular, placentation parietal; ovules several; perianth-tube narrowly cylindric; styles 6–8; stigmas 6–8, deeply 2-lobed, filiform, papillose Female spathe solitary in the leaf-axil, pedunculate, 1-flowered, composed of 2 connate bracts, cylindric, but tapering at both ends, translucent, 2-lobed at the apex, the lobes acute to obtuse
    Fruits
    Fruit globose, beaked, densely hairy, opening by stellate dehiscence of the carpels
    Seeds
    Seeds conical with a thickened basal portion.

    Images

    Distribution

    Native to:

    Alabama, Aldabra, Andaman Is., Aruba, Bahamas, Belize, Bermuda, Bismarck Archipelago, Borneo, Caroline Is., Cayman Is., Cocos (Keeling) Is., Colombia, Costa Rica, Cuba, Djibouti, Dominican Republic, Egypt, Eritrea, Florida, Gilbert Is., Guatemala, Hainan, Haiti, Honduras, India, Jamaica, Jawa, Kenya, Laccadive Is., Leeward Is., Lesser Sunda Is., Louisiana, Madagascar, Malaya, Maldives, Maluku, Marianas, Marshall Is., Mexico Gulf, Mexico Northeast, Mexico Southeast, Mozambique, Myanmar, Nansei-shoto, Netherlands Antilles, New Caledonia, New Guinea, Nicaragua, Nicobar Is., Panamá, Philippines, Puerto Rico, Queensland, Saudi Arabia, Seychelles, Solomon Is., Somalia, South China Sea, Southwest Caribbean, Sri Lanka, Sudan, Sulawesi, Sumatera, Taiwan, Tanzania, Texas, Thailand, Trinidad-Tobago, Turks-Caicos Is., Venezuela, Venezuelan Antilles, Vietnam, Western Australia, Windward Is., Yemen

    Thalassia Banks & Sol. ex K.D.Koenig appears in other Kew resources:

    First published in Ann. Bot. (König & Sims) 2: 96 (1805)

    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 Tropical East Africa
    • Hartog, Sea Grasses of the World: 222 (1970)
    • G.P. 3: 455 (1883)
    • Ann. Bot. 2: 96 (1805)

    Sources

    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 2018. 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 2018. 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