The Potamogetonaceae, commonly referred to as the pondweed family, is an aquatic family of monocotyledonous flowering plants. The roughly 110 known species are divided over five genera.

Taxonomy

The Potamogetonaceae are currently placed in the early diverging monocot order Alismatales by the Angiosperm Phylogeny Group.)

! scope="col" | Watson & Dallwitz (delta-intkey)

! scope="col" | data.kew

! scope="col" | APWeb (mobot.org)

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! colspan="4" | Zosteraceae

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| 1. Zostera L. || Zostera || Zostera L. || Zostera L. (including Heterozostera den Hartog, Macrozostera Tomlinson & Posluzny, Nanozostera Tomlinson & Posluzny, Zosterella J. K. Small)

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| 2. Heterozostera den Hartog || Heterozostera || Heterozostera (Setch.) Hartog || (in Zostera)

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| 3. Phyllospadix Hook. || Phyllospadix || Phyllospadix Hook. || Phyllospadix J. D. Hooker

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! colspan="4" | Cymodoceaceae

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| 1. Syringodium Kütz || Syringodium || Syringodium Kutz. || (in Cymodocea)

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| 2. Halodule Endl. || Halodule || Halodule Endl. || Halodule Endlicher

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| 3. Cymodocea König ||Cymodocea ||Cymodocea K.Koenig (including Phycoschoenus (Asch.) Nakai ) || Cymodocea König (including Amphibolis Agardh ?, Syringodium Kütz. ?, Thalassodendron den Hartog ?)

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| 4. Amphibolis Agardh || Amphibolis || Amphibolis C.Agardh (including Pectinella J.M.Black) || (in Cymodocea)

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| 5. Thalassodendron de Hartog || (name not found) || Thalassodendron Hartog || (in Cymodocea)

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! colspan="4" | Ruppiaceae

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| Ruppia L. || Ruppia || (in Ruppia L. in Potamogetonaceae) || Ruppia L.

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! colspan="4" | Posidoniaceae

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| Posidonia König || Posidonia || Posidonia K.Koenig || Posidonia König

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|}

{| class="wikitable" style="margin:1em auto;"

|+ Families and Genera crosses (Potamogetonaceae)

! scope="col" | Kubitzki (ed. 1998

! scope="col" | data.kew

! scope="col" | APWeb (mobot.org)

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! colspan="4" | Potamogetonaceae

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| 1. Potamogeton L. || Potamogeton || Potamogeton L. || Potamogeton L. (including Coleogeton Les & Haynes, Stuckenia Börner)

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| 2. Groenlandia J. Gray || Groenlandia || Groenlandia J.Gay || Groenlandia J. Gay

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| (in Ruppia in Ruppiaceae) || (in Ruppia in Ruppiaceae) || Ruppia L. || (in Ruppia in Ruppiaceae)

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| (in Althenia: Zannichelliaceae and Lepilaena: Zannichelliaceae) || (in Althenia: Zannichelliaceae and Lepilaena: Zannichelliaceae) || (in Althenia F.Petit: Zannichelliaceae and Lepilaena J.L.Drumm. ex Harv.:Zannichelliaceae) || Althenia Petit (including Lepilaena Harvey)

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| (in Pseudalthenia including Vleisia: Zannichelliaceae) || (in Pseudalthenia: Zannichelliaceae and Vleisia: Zannichelliaceae) || (Pseudalthenia not found, Vleisia Toml. & Posl.: Zannichelliaceae) || Pseudalthenia Nakai (including Vleisia Tomlinson & Posluszny)

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| (in Zannichellia L.: Zannichelliaceae) || (in Zannichellia: Zannichelliaceae) || (in Zannichellia L.: Zannichelliaceae) || Zannichellia L.

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! colspan="4" | Zannichelliaceae

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| 1. Zannichellia L. || Zannichellia || Zannichellia L. || (in Zannichellia L.: Potamogetonaceae)

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| 2. Pseudalthenia Nakai (including Vleisia) || Pseudalthenia (excluding Vleisia) || (name not found) || (in Pseudalthenia: Potamogetonaceae)

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| 3. Althenia Petit (excluding Lepilaena Drumm. ex. Harv.) || Althenia (excluding Lepilaena) || Althenia F.Petit (excluding Lepilaena J.L.Drumm. ex Harv.) || Althenia Petit (including Lepilaena Harvey)

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| 4. Lepilaena Drumm. ex. Harv. || Lepilaena || Lepilaena J.L.Drumm. ex Harv. || (in Althenia Petit)

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| (in Pseudalthenia) || Vleisia || Vleisia Toml. & Posl. || (in Pseudalthenia: Potamogetonaceae)

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|}

Characteristics

The plants are all aquatic perennial herbs, often with creeping rhizomes and leafy branches. Their leaf blades can be either floating or submerged, and their stems are often joined. No stomata are present on the leaves. The flowers are tetramerous: the floral formula (sepals; petals; stamens; carpels) is [4;0;4;4]. The flowers have no petals. The fruit consists of one to four drupelets or achenes.

References

  • Angiosperm Phylogeny Website
  • Potamogetonaceae at the DELTA Online Families of Flowering Plants
  • Potamogetonaceae at the Germplasm Resources Information Network
  • Potamogetonaceae at the Online Flora of North America
  • Zannichelliaceae at the Online Flora of North America
  • Potamogetonaceae at the NCBI Taxonomy Browser