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Potamogeton × Concilius
''Potamogeton'' is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed (''Elodea canadensis''). The genus name means "river neighbor", originating from the Greek ''potamos'' (river) and ''geiton'' (neighbor). Morphology ''Potamogeton'' species range from large (stems of 6 m or more) to very small (less than 10 cm). Height is strongly influenced by environmental conditions, particularly water depth. All species are technically perennial, but some species disintegrate in autumn to a large number of asexually produced resting buds called turions, which serve both as a means of overwintering and dispersal. Turions may be borne on the rhizome, on the stem, or on stolons from the rhizome. Most species, however, persist by perennial creeping rhizomes. In some cases the turions are the only means to differentiate species. The leave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Perfoliatus
''Potamogeton perfoliatus'' (claspingleaf pondweed, perfoliate pondweed, redhead grass) is a perennial aquatic plant in the family Potamogetonaceae occurring in both standing and flowing freshwater habitats. It is widely distributed globally, occurring in all continents except South America and Antarctica. Description Perfoliate pondweed grows from a robust creeping perennial rhizome, intermittently producing round stems up to 3 m long. The submerged leaves are oval and translucent, with no stalk, 20–115 mm long and 7–42 mm wide, clasping the stem (perfoliate), a flat apex, and 5–12 veins on either side of the midrib. They vary considerably in colour and may be bright green, dark green, yellowish, olive or brownish. There are no floating leaves. The stipules are rather delicate and usually fall off quite soon after the new leaf has unfurled. The insignificant flowers are produced between June and September. Fruits are 4 mm across, olive green in colour. Two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Alpinus
''Potamogeton alpinus'' is a species of perennial aquatic plant known by the common names alpine pondweed and red pondweed. It is widespread in the northern hemisphere in both rivers and lakes with good water quality. Description Red pondweed is a perennial herb anchoring in the mud substrate via a creeping rhizome. It produces a cylindrical unbranched stem, up to 2.8 m in length. It has sessile lance-shaped submerged leaves that are typically 70–180 mm long and 10–25 mm wide with 4–7 lateral veins on either side and a slightly hooded apex, with an untoothed margin. Floating leaves may also be produced. The inflorescence is a spike of flowers a few centimeters long rising above the water surface. Turion (botany), Turions are absent, but in winter each stem dies back to a resting bud with a short length of root, which acts as a functional turion. Red pondweed is a reasonably distinctive plant and is not likely to be confused with any other pondweed. Early in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxonomy (biology)
In biology, taxonomy () is the science, scientific study of naming, defining (Circumscription (taxonomy), circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxon, taxa (singular: taxon), and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a more inclusive group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain (biology), domain, kingdom (biology), kingdom, phylum (''division'' is sometimes used in botany in place of ''phylum''), class (biology), class, order (biology), order, family (biology), family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, having developed a ranked system known as Linnaean taxonomy for categorizing organisms. With advances in the theory, data and analytical technology of biological systematics, the Linnaean system has transfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid (biology)
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a different organism is called a chimera. Hybrids are not always intermediates between their parents such as in blending inheritance (a now discredited theory in modern genetics by particulate inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are. Species are reproductively isolated by strong barriers to hybridization, which include genetic and morph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamogeton Crispus
''Potamogeton crispus'', the crisp-leaved pondweed, curly pondweed, curly-leaf pondweed or curled pondweed, is a species of aquatic plant (hydrophyte) native to Eurasia but an introduced species and often a noxious weed in North America. Description Curly-leaf pondweed is a rhizome, rhizomatous perennial herb producing a flattened, branching stem up to a meter long. The submerged leaves are alternately arranged. The leaves are sessile, linear or oblong in shape, long and wide. The leaves may be bright green, olive green or (especially later in the season) fibrous and brownish and have noticeably serrated margins, a feature that distinguishes them from other pondweeds. The leaves usually have wavy edges but this is not always apparent, especially on new growth. Turion (botany), Turions occur in leaf axils and at stem tips. The inflorescence is a short spike of flowers emerging above the water surface. It flowers from May until October. The turions of the plant develop along w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stuckenia
''Stuckenia'' is a genus of flowering aquatic plants. It contains approximately 30 species that grow in shallow water. Pondweed is a common name for plants in this genus. Description These herbs have rhizomes but not turions. Tubers can be absent or present. The main difference between ''Stuckenia'' and ''Potamogeton'' is that the stipule joins the leaf base. When it is pulled the sheath and stipule comes away, similar to a grass sheath and ligule A ligule (from "strap", variant of ''lingula'', from ''lingua'' "tongue") is a thin outgrowth at the junction of leaf A leaf (: leaves) is a principal appendage of the plant stem, stem of a vascular plant, usually borne laterally above g .... Species :* '' Stuckenia aldanensis'' :* '' Stuckenia amblyophylla'' :* '' Stuckenia arctovaginata'' :* '' Stuckenia austrosibirica'' :* '' Stuckenia borealis'' :* '' Stuckenia bottnica'' :* '' Stuckenia carbonata'' :* '' Stuckenia chakassiensis'' :* '' Stuckenia clavata'' :* '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Althenia
''Althenia'' is a genus of aquatic plants of the family Potamogetonaceae. This has long been a group of two species in the Mediterranean Europe and South Africa, but in 2016 was revised to include an Australasian relative, ''Lepilaena''. The genus is named after the agronomist Jean Althen. Description This genus is made up of aquatic herbs. The bristle-like leaves are clustered at the nodes. The wider bases produce broad ligules. The flowers are unisexual. The male flowers have a perianth made of three minute scales and have a single stamen. The female flowers have a perianth made of one to three segments. The gynoecium has three carpels with a single pendulous ovule in each ovary. The filiform styles gradually pass into the carpels and the stigmas are large and oblique. The mature carpels are oblique and compressed with a winged or thickened margin. The seeds are pendulous, oblong and compressed. The embryo is straight. Species :* ''Althenia australis'' (aquatic) :* ''Altheni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
