Pondweed at Watson, ACT
Identification history
| Potamogeton cheesemanii | 19 Feb 2019 | BettyDonWood | ||
| Potamogeton sulcatus | 19 Feb 2019 | BettyDonWood | ||
| Potamogeton cheesemanii | 19 Feb 2019 | JaneR |
Identify this sighting
Please Login or Register to identify this sighting.
User's notes
urban wetland, receiving overflow from Billabong Wetland, Watson. Fringed by Bolboschoenus ?medianus. Potamogeton growing with Egeria densa and Vallisneria australis, all in flower: in water about 75 cm deep; heavy epiphytic load.
3 comments
BettyDonWood
wrote:
19 Feb 2019
The leaves appear to be too big for cheesemanii and the number of flowers in the inflorescence too many. The Vicflora key: cheesemanii - floating leaves 0.8-5 cm long, 1-3.5 cm wide, inflorescence usually fewer than 20 flowers; sulcatus - floating leaves 4-8 cm long, 3-5.5 cm wide; inflorescence usually more than 20 flowers. Please comment.
JaneR
wrote:
19 Feb 2019
Yes, I used the Vic key (on-line version updated 2014 which gives slightly different range leaf size for cheesemanii, not as small as 0.8 cm). Specimen taken, currently being pressed.
Floating leaves are 4.6 cm long x 2.9 cm wide, and have 18 veins, excluding central.
Submerged leaves (which are a bit decayed and disintegrated) were up to 10 cm long x 2.5 cm wide, and have 12 veins excluding central (but not very distinct).
Inflorescence appears to have about 24 flowers, and is 2.2 cm long.
Floating leaf size fits either species but vein count matches cheesemannii better. Submerged leaf size fits better with sulcatus, vein count not helpful. Inflorescence number of flowers is just on range for cheesemanii (12-24) but fits sulcatus better (20-60), however overall size fits cheesemanii (1.0-2.5 cm) better than sulcatus (3.2 - 5.0 cm).
There wasn't a clear separation, and I suggested cheesemanni because of vein count, and inflorescence length.
Floating leaves are 4.6 cm long x 2.9 cm wide, and have 18 veins, excluding central.
Submerged leaves (which are a bit decayed and disintegrated) were up to 10 cm long x 2.5 cm wide, and have 12 veins excluding central (but not very distinct).
Inflorescence appears to have about 24 flowers, and is 2.2 cm long.
Floating leaf size fits either species but vein count matches cheesemannii better. Submerged leaf size fits better with sulcatus, vein count not helpful. Inflorescence number of flowers is just on range for cheesemanii (12-24) but fits sulcatus better (20-60), however overall size fits cheesemanii (1.0-2.5 cm) better than sulcatus (3.2 - 5.0 cm).
There wasn't a clear separation, and I suggested cheesemanni because of vein count, and inflorescence length.
BettyDonWood
wrote:
20 Feb 2019
Like a lot of theses new species, specimens from outside the area of collectiom when the original paper was written can often fall between, which suggests they should not have been separated in the first place.
The length I mentioned of 0.8 cm is in the Vicflora key, which separates sulcatus from two other species. The Vicflora article on cheesemanii states the length is 1.5-5 cm..
The length I mentioned of 0.8 cm is in the Vicflora key, which separates sulcatus from two other species. The Vicflora article on cheesemanii states the length is 1.5-5 cm..
Please Login or Register to comment.
Nearby sightings
Location information
- Coordinates 149.154922-35.232125
- Altitude 589.9m
- Maps Watson Green Space
- Places Watson, ACT
Sighting information
- 16 - 100 Abundance
- 18 Feb 2019 04:07 PM Recorded on
- JaneR Recorded by
Additional information
- True In flower
Species information
- Potamogeton cheesemanii Scientific name
- Pondweed Common name
- Not Sensitive
- Local native
- Non-Invasive
- Up to 1127.5m Recorded at altitude
- Machine learning
-
In flower
- External link More information
Record quality
- Images or audio
- More than one media file
- Confirmed by an expert moderator
- Nearby sighting(s) of same species
- GPS evidence of location
- Description
- Additional attributes
