The New Zealand Plant Conservation Network

Species

Potamogeton cheesemanii

Etymology

Potamogeton: river dweller
cheesemanii: Named after Thomas Frederick Cheeseman (1846 - 15 October 1923) who was a New Zealand botanist and naturalist who, in 1906, produced The Manual of the New Zealand Flora.

Common Name(s)

red pondweed

Current Conservation Status

2012 - Not Threatened

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Not Threatened
2004 - Not Threatened

Authority

Potamogeton cheesemanii A.Benn.

Family

Potamogetonaceae

Flora Category

Vascular - Native

NVS Species Code

POTCHE

Structural Class

Monocotyledonous Herbs

Synonyms

None

Distribution

Indigenous. New Zealand: North, South, Stewart and Chatham Islands. Also Australia.

Habitat

Coastal to montane - but mostly found in coastal and lowland areas. A common plant of ponds, lake margins and slowly flowing streams. Also colonising roadside ditches. rarely found in muddy hollows within forest.

Features

Aquatic, submerged or floating, rhizomatous sparsely branched perennial herb. Rhizomes rooting at nodes and producing mostly simple leafy branches; these ultimately water surface. Stipules membranous, free, open. Leaves dimorphic. Submersed leaves usually rather distant, usually shortly petiolate; lamina c. 40–100 × 5–15 mm, narrowly elliptic, entire, subacute, delicate, ± translucent, longitudinal nerves c. 5–11, irregularly joined by cross veins. Floating leaves often long-petiolate; lamina 20–40 × 10–25 mm, broad oblong-oval, entire, usually quite obtuse, firm and opaque, longitudinal nerves 10–15, laterals emerging from petiole rather than from midrib. Inflorescence a densely flowered spike, 10-25 mm long. Peduncles in axils of floating leaves, stout, erect, usually projecting above surface of water at flower, submersed in fruit. Achene c.2.5 × 1.5 mm, green, green-brown or brown, moderately flattened with rather strongly 3-ridged keel and short straight beak.

Similar Taxa

Distinguished from Potamogeton suboblongus by the strongly dimorphic foliage (i.e. clear distinction between submerged and emergent leaves), by the narrowly elliptic, ± translucent submerged leaves; floating leaves which are mostly broad-oval, with obtuse apices, and which have usually 6 or less (rarely an unequal higher number) nerves on either side of midrib; and by the green, green-brown or brown, flattened achenes which are 3-keeled when dry. In its submerged state Potamogeton cheesemanii could be confused with P. ochreatus from which it differs by non-fibrous stipules, and submerged and emergent elliptic to broadly oval leaves with well separated rather than closely set longitudinal nerves.

Flowering

November - March

Flower Colours

Cream,Red / Pink

Fruiting

December - March

Propagation Technique

Easily grown from rooted pieces and fresh seed, An attractive plant for a large pond or similar water body but inclined to become aggressive in fertile waters.

Threats

Not Threatened

Chromosome No.

2n = 28

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

This page last updated on 11 Aug 2014