Pondweed family
| Pondweed family | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Knotweed pondweed ( Potamogeton polygonifolius ), illustration |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Potamogetonaceae | ||||||||||||
| Bercht. & J. Presl |
The pondweed plants (Potamogetonaceae) are a family of plants in the order of the frog-spoon-like (Alismatales) within the monocotyledons . These aquatic plants thrive almost worldwide in almost all climate zones only in fresh or brackish water , but never in the sea. The best-known and most common species in Central Europe is the floating pondweed ( Potamogeton natans ), which can form large carpets of floating leaves on water.
description
Habit and leaves
It is rarely one-year ( Althenia , Pseudalthenia , Zannichellia ), mostly perennial herbaceous plants . They are diving, floating or floating leaf plants ( hydrophytes ) rooted in the water bed . Some species form rhizomes or stolons. Some species develop stems up to 3 meters long and colonize correspondingly deep water zones.
The generally alternate, in the genus Groenlandia opposite or scheinwirtelig arranged on the stem leaves are divided into leaf sheath and blade least, usually a more or less long petiole is present. The leaf blade, which is often translucent as a network nerve, varies in shape from thread-like ( Zannichellia ) to narrow, linear to rounded. There are both very delicately built species and those with strong underwater and / or swimming leaves. The leaf edges can be smooth or serrated. There are scales in the leaf axils. Some species are heterophyllous with swimming and underwater leaves.
Inflorescences, flowers and fruits
The inconspicuous greenish, spiked or zymous inflorescences are either terminal and emersed (protruding from the water) for wind pollination or lateral and submerged (remaining under water) with water pollination . There are taxa with hermaphroditic and unisexual ( Zannichellia ) flowers. In some species there is a male and female flower in the leaf axils. In the male and hermaphroditic flowers, the missing flower envelope is replaced by four stamen appendages. The female flowers have three to four bracts. There are one to four fertile stamens . The mostly four (one to eight) upper carpels are free. One ovule with marginal placentation is present per carpel .
The fruits are solitary and stone fruit - to berry-like .
Chromosomes
The chromosomes are 0.5 to 2.3 µm long. The number of chromosomes is n = 7, 12 or 14-18. Especially in the genus Potamogeton , many species are tetraploid and hexaploid ( polyploidy ).
Ecology and occurrence
Laichkrautgewächse are the eponymous and characteristic family of the plant sociological class of Potamogetonetea pectinati R.Tx. & Prsg. 1942 corr. Oberd. 1979 (= Laichkraut- und Schwimmblatt- societies) and several different associations and dominance societies. The plants form "underwater forests", which offer numerous animals a habitat and opportunities to lay eggs and spawn (name!) As well as contribute to the oxygen supply and self-cleaning of a body of water.
Different types of water bodies are settled: Still water bodies such as ponds, ponds, small ponds and diving leaf zones of large lakes, but also weak to moderately flowing water bodies such as streams, rivers, canals and ditches. Some species are adapted to less nutrient-poor locations; however, most prefer moderately eutrophic waters. As a result of human intervention in the landscape - including water pollution, river straightening, ditch clearance, artificial fish stocking - many species of pondweed have become rare and are on the red list of endangered plant species. The spread of the neophytic , anthropogenically naturalized waterweed in Europe also displaced some stocks of pondweed.
Systematics and distribution
The species of the family Potamogetonaceae are distributed in almost all climates almost worldwide, except in the large desert areas.
The family name Potamogetonaceae was first published in 1823 by Friedrich von Berchtold & Jan Svatopluk Presl in O Prirozenosti rostlin , 1 (7), 1, 3. Also Ludwig Reichenbach with a publication in 1928 and Barthélemy Charles Joseph Dumortier in 1829 in analysis of the familles des plantes… , 59, 61 are given as authors for first-time publications. The type genus is Potamogeton L.
For a long time this family contained only the two genera: Potamogeton and Groenlandia . Molecular genetic studies led to the removal of Stuckenia from Potamogeton (Les et al. 1997). The scope of the family was often debated, and some genera belonged to the families Cymodoceaceae , Najadaceae , Zosteraceae, and Zannichelliaceae. The four to five genera ( Althenia , Lepilaena , Pseudalthenia , Vleisia , Zannichellia ) of the earlier pond thread plants (Zannichelliaceae Chevall. ) Now belong to the Potamogetonaceae. Another synonym is Hydrogetonaceae Link . Ruppia L. is not counted among the Potamogetonaceae, they form their own family of the balance plants (Ruppiaceae). Within the order of the Alismatales , the Potamogetonaceae are related to the Aponogetonaceae , Cymodoceaceae, Juncaginaceae , Ruppiaceae , Scheuchzeriaceae and Zosteraceae.
Today the family includes about seven genera with 96 to a little over 100 species:
-
Althenia F.Petit (Syn .: Belvalia Delile , Bellevalia Delile ex Endl. Nom. Illeg.): The two to three annual species are distributed from the Mediterranean to Central Asia and in Southern Africa:
- Althenia filiformis F.Petit : It occurs with two varieties in southern and western Europe only in France (Bouches du Rhône, Gard, Hérault) and Italy (Puglia) in brackish water.
- Althenia orientalis (Tzvelev) García-Mur. & Talavera : It is distributed with two subspecies from the Mediterranean area to Central Asia and southern Africa.
-
Groenlandia J.Gay : It contains only one species:
- Fishweed or Dense Laichkraut ( Groenlandia densa (L.) Fourr. ): The wide distribution area extends from Europe over the Mediterranean to western Iran .
- Lepilaena J. Drumm. ex Harv. (Syn .: Hexatheca Sond. Ex F. Muell. ): The six or so species are distributed from southern and eastern Australia to New Zealand.
- Spawning herbs ( Potamogeton L. , Syn .: Hydrogeton Lour. , Peltopsis Raf. , Spirillus J.Gay , Buccaferrea Bubani nom. Illeg.): The 75 to 90 species are distributed almost worldwide.
-
Pseudalthenia (Graebn.) Nakai (Syn .: Vleisia Toml. & Posl .; It probably belongs to Zannichellia P.Micheli ex L. ): It contains only one species:
- Pseudalthenia aschersoniana (Graebn.) Hartog : It is endemic to the western western cape from Lamberts Bay to the Cape Peninsula and thrives as an annual plant in brackish water and in coastal still waters .
-
Stuckenia Börner (Syn .: Coleogeton (Reichenb.) Les & RRHaynes ): The six to seven species and three natural hybrids are distributed almost worldwide. These include a .:
- Filiform pondweed ( Stuckenia filiformis (Pers.) Börner , Syn .: Potamogeton filiformis Pers. )
- Swiss pondweed ( Stuckenia helvetica (G. Fisch.) Holub , Syn .: Potamogeton helveticus (G. Fisch.) Walo Koch )
- Crested pondweed ( Stuckenia pectinata (L.) Börner , Syn .: Potamogeton pectinatus L. )
- Stuckenia vaginata (Turcz.) Holub , Syn .: Potamogeton vaginatus Turcz.
-
Pond thread ( Zannichellia P.Micheli ex L. , Syn .: Pelta Dulac nom. Superfl., Pseudalthenia (Graebn.) Nakai , Vleisia Toml. & Posl. ): The (four to) about six species are distributed almost worldwide. The number and delimitation of the species is controversial. For example, some authors (see Flora of China ) assume that there is only one species, which is rich in forms:
- Swamp pond thread ( Zannichellia palustris L. )
swell
- The Potamogetonaceae family on the AP website . (Sections systematics and description)
- Charlotte Lindqvist, Jan De Laet, Robert R. Haynes, Lone Aagesen, Brian R. Keener, Victor A. Albert: Molecular phylogenetics of an aquatic plant lineage, Potamogetonaceae. In: Cladistics. Volume 22, No. 6, 2006, pp. 568-588, doi: 10.1111 / j.1096-0031.2006.00124.x .
- A. Haigh: Neotropical Potamogetonaceae : online - Royal Botanic Gardens Kew . (Section description)
- Robert R. Haynes, C. Barre Hellquist: Potamogetonaceae (excluding Zannichelliaceae). In: Flora of North America Editorial Committee (Ed.): Flora of North America North of Mexico . Volume 22: Magnoliophyta: Alismatidae, Arecidae, Commelinidae (in part), and Zingiberidae . Oxford University Press, New York / Oxford a. a. 2000, ISBN 0-19-513729-9 , pp. 47–74 (English, limited preview in Google Book Search). , online.
- Robert R. Haynes, C. Barre Hellquist: Zannichelliaceae. In: Flora of North America Editorial Committee (Ed.): Flora of North America North of Mexico . Volume 22: Magnoliophyta: Alismatidae, Arecidae, Commelinidae (in part), and Zingiberidae . Oxford University Press, New York / Oxford a. a. 2000, ISBN 0-19-513729-9 , pp. 84–85 (English, limited preview in Google Book Search). , online .
- Youhao Guo, Robert R. Haynes, C. Barre Hellquist, Zdenek Kaplan: Potamogetonaceae (excluding Zannichelliaceae). In: Wu Zheng-yi, Peter H. Raven, Deyuan Hong (Eds.): Flora of China . Volume 23: Acoraceae through Cyperaceae . Science Press / Missouri Botanical Garden Press, Beijing / St. Louis 2010, ISBN 978-1-930723-99-3 , pp. 108 (English). , online , PDF file .
- Youhao Guo, Robert R. Haynes, C. Barre Hellquist: Zannichelliaceae. In: Wu Zheng-yi, Peter H. Raven, Deyuan Hong (Eds.): Flora of China . Volume 23: Acoraceae through Cyperaceae . Science Press / Missouri Botanical Garden Press, Beijing / St. Louis 2010, ISBN 978-1-930723-99-3 , pp. 116 (English). , online , PDF file .
- The family of Potamogetonaceae (without Zannichelliaceae) with two genera and The family of Zannichelliaceae with five genera at DELTA by L. Watson & MJ Dallwitz.
Individual evidence
- ^ QD Wang, T. Zhang, JB Wang: Phylogenetic relationships and hybrid origin of Potamogeton species (Potamogetonaceae) distributed in China: insights from the nuclear ribosomal internal transcribed spacer sequence (ITS). In: Plant Systematics and Evolution. Volume 267, No. 1-4, 2007, pp. 65-78, doi: 10.1007 / s00606-006-0499-5 .
- ↑ Potamogetonaceae at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed August 21, 2014.
- ↑ Potamogetonaceae in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.
- ↑ a b c d e f g h Rafaël Govaerts (Ed.): Potamogetonaceae. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved August 21, 2014.
- ↑ James Edward Dandy : Althenia Petit . In: TG Tutin, VH Heywood, NA Burges, DM Moore, DH Valentine, SM Walters, DA Webb (eds.): Flora Europaea . Volume 5: Alismataceae to Orchidaceae (Monocotyledones) . Cambridge University Press, Cambridge 1980, ISBN 0-521-20108-X , pp. 13 (English, limited preview in Google Book search).
- ^ Zdeněk Kaplan: A Taxonomic Revision of Stuckenia (Potamogetonaceae) in Asia, with Notes on the Diversity and Variation of the Genus on a Worldwide Scale. In: Folia Geobotanica. Volume 43, No. 2, 2008, pp. 159-234, doi: 10.1007 / s12224-008-9010-0 , PDF file.
