Spotted Pondweed at suppressed
Identification history
| Landoltia punctata | 20 Feb 2025 | JaneR | ||
| Landoltia punctata | 20 Feb 2025 | JaneR | ||
| Lemna sp. | 19 Feb 2025 | MazzV |
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User's notes
I suspect this is brought in by birds when drinking or bathing. Tiny plant with roots that dangle down into the water from underneath the floating leaf structure. The last 4 photos, with thanks to JaneR for her suggestions, depict the undersides to show the root structure. The underside of the thallus is green and I’ve not noticed any purple or red tinges there. There appears to be mostly 2, occasionally 3 roots from each thallus. (I’m taking thallus to mean all 2-3 lobes of a single plant). The roots seem to emanate from the point at which the lobes join.
4 comments
JaneR
wrote:
19 Feb 2025
this needs a bit more information to work out which of three possible genera this is.
Are you able to check the following:
Q: Is underside of the thallus green; occasionally purplish; or tinged red ?
Q: how many roots are dangling from each thallus: just 1; up to 12; or up to 18 ?
A clear close-up of thallus taken vertically from above would be a help too.
Are you able to check the following:
Q: Is underside of the thallus green; occasionally purplish; or tinged red ?
Q: how many roots are dangling from each thallus: just 1; up to 12; or up to 18 ?
A clear close-up of thallus taken vertically from above would be a help too.
MazzV
wrote:
20 Feb 2025
Hi JaneR,
Thank you for those suggestions, I've learnt more from those than I did trying to find out more about it independently. I've just gone to find some more lemna (the original lot has since disappeared!) So I've managed a few hopefully helpful close-ups, along your suggested lines. They were tricky beasts to separate & place for the exercise and I wasn't highly successful in doing that! I've just posted them so hope they provide the appropriate information.
Cheers,
MazzV
Thank you for those suggestions, I've learnt more from those than I did trying to find out more about it independently. I've just gone to find some more lemna (the original lot has since disappeared!) So I've managed a few hopefully helpful close-ups, along your suggested lines. They were tricky beasts to separate & place for the exercise and I wasn't highly successful in doing that! I've just posted them so hope they provide the appropriate information.
Cheers,
MazzV
JaneR
wrote:
20 Feb 2025
From what I can see of rootlets and venation, it looks like Landoltia punctata (also known as Spirodela punctata). True, it doesn't have a purplish underside but according to PlantNet the underside of Landoltia punctata is "often purplish". Thanks for effort in taking underside and rootlets. Observations (text) would have worked too (I should have made that clear). Here are two sightings (4197436 and 4424808: just put number into Quick Search) with ideas on ways to photograph rootlets.
"Duckweed" is a general term for Lemna, Landoltia, Spirodela and Wolffia.
"Duckweed" is a general term for Lemna, Landoltia, Spirodela and Wolffia.
MazzV
wrote:
20 Feb 2025
Great photos, JaneR!
I've been thinking of setting up a 'Terraquarium' for observing some of the local frogs, basically a glass tank, with back & front separated to a middling height, so that the back section has terrestial plants and the front is a water environment. That would work brilliantly for these types of photos.
Thanks for the references. Some interesting differences between the 2 plants depicted at sightings 4197436 and 4424808, though they share the same botanic name. I guess another illustration of that is Brassica oleracea which, as edible plants go, comes in all shapes, forms & sizes, from kale to brussels, cauliflower to broccoli; notwithstanding thousands of years of human influence in this example.
All the best Jane, and thanks for all your info, it's been great to 'meet you',
Cheers,
MazzV
I've been thinking of setting up a 'Terraquarium' for observing some of the local frogs, basically a glass tank, with back & front separated to a middling height, so that the back section has terrestial plants and the front is a water environment. That would work brilliantly for these types of photos.
Thanks for the references. Some interesting differences between the 2 plants depicted at sightings 4197436 and 4424808, though they share the same botanic name. I guess another illustration of that is Brassica oleracea which, as edible plants go, comes in all shapes, forms & sizes, from kale to brussels, cauliflower to broccoli; notwithstanding thousands of years of human influence in this example.
All the best Jane, and thanks for all your info, it's been great to 'meet you',
Cheers,
MazzV
Sighting information
- 300 Abundance
- MazzV Recorded by
-
Collections
MazzV NatureMapr Other Fresh Water Plants Plants Landoltia punctata
Additional information
- Less than 10cm Plant height
Species information
- Landoltia punctata Scientific name
- Spotted Pondweed Common name
- Highly Sensitive
- Local native
- Non-invasive or negligible
- External link More information
-
Synonyms
Spirodela punctata
Record quality
- Images or audio
- More than one media file
- Verified by an expert moderator
- Nearby sighting(s) of same species
- GPS evidence of location
- Description
- Additional attributes