''
Hygrophila'', commonly known as swampweeds, is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
s in the acanthus family,
Acanthaceae
Acanthaceae is a family (the acanthus family) of dicotyledonous flowering plants containing almost 250 genera and about 2500 species. Most are tropical herbs, shrubs, or twining vines; some are epiphytes. Only a few species are distributed in te ...
. There are about 80
[''Hygrophila''.]
Flora of Pakistan. to 100
[''Hygrophila''.]
Flora of China.[Hài, Đ. V. and D. Đ. Huyến. (2012)]
New record of species ''Hygrophila episcopalis'' R. Ben. (R. Ben.) (Acanthaceae) for the flora of Vietnam.
''Journal of Biology'' 34(2), 187-89. species, of which many are
aquatic plant
Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...
s. The genus is distributed across the tropical and subtropical world.
[ It is one of only two genera in its family that contains aquatic plants, the other being '' Justicia''. The genus is treated in the tribe ''Hygrophileae'', which is noted as being in need of revision at the genus level, meaning the current taxonomic boundaries of ''Hygrophila'' are likely to change in the future.][
]
Description
The leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...
are either homomorphic, all with one form, or heteromorphic, with different forms on one plant. Homomorphic leaves are always simple and entire. Plants with heteromorphic leaves generally have pinnate
Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and in ...
ly divided basal leaves with either filiform (feather-like) or linear segments, and undivided leaves higher on the stem.flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...
s have white to purple corollas with either 5 equal lobes or 2 lips. A lipped corolla has an erect, concave upper lip with two lobes, and a lower lip with 3 lobes. The flower has four stamen
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10
Morphology and terminology
A stamen typically consists of a stalk called the filame ...
s. Two may be staminodal, lacking pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...
. The individual filaments of the stamens are united into pairs by a membrane. There is an inconspicuous nectar disc. Each flower yields at least 6 seeds.[
]
Ecology and uses
A number of species are cultivated for the aquarium
An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...
trade, including '' H. difformis'' (water wisteria) and ''Hygrophila polysperma
''Hygrophila polysperma'', commonly known as dwarf hygrophila, dwarf hygro, Miramar weed, Indian swampweed or Indian waterweed, is an aquatic plant in the family Acanthaceae. It is native to Bangladesh, India, China and Malaysia, and has also be ...
'' (Indian swampweed). Many members of the genus are troublesome weeds in irrigation and drainage ditches as well as rice fields. Several have become established outside of their native ranges, largely due to the aquarium trade, such as ''H. polysperma'' in the southern United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
.[
]
Gallery
File:Hygrophila serpyllum in Hyderabad, AP W IMG 4437.jpg, ''Hygrophila serpyllum
Hygrophila may refer to:
* Hygrophila (gastropod)
Hygrophila is a taxonomic superorder of air-breathing freshwater snails, aquatic pulmonate gastropod mollusks within the clade Panpulmonata. MolluscaBase eds. (2020). MolluscaBase. Hygrophi ...
''
File:Hygrophila difformis.jpg, ''Hygrophila difformis
''Hygrophila difformis'', commonly known as water wisteria (though it is not closely related to true wisteria), is an aquatic plant in the acanthus family. It is found in marshy habitats on the Indian subcontinent in Bangladesh, Bhutan, India an ...
''
File:Hygrophila schulli Acanthaceae.jpg, ''Hygrophila schulli
''Hygrophila auriculata'' (Sanskrit: , Bangla (বাংলা নাম): (কুলেখাড়া) ''kokilākṣa'') is a herbaceous, medicinal plant in the acanthus family that grows in marshy places and is native to tropical Asia and A ...
''
File:Hygrophila pogonocalyx.jpg, ''Hygrophila pogonocalyx
''Hygrophila pogonocalyx'' is a species of flowering plant in the family Acanthaceae
Acanthaceae is a family (the acanthus family) of dicotyledonous flowering plants containing almost 250 genera and about 2500 species. Most are tropical herb ...
''
References
External links
*
''Hygrophila'' subordinate taxa.
Tropicos.
''Hygrophila''.
The Plant List.
{{Taxonbar, from=Q241151
Acanthaceae genera