AquaNISInformation system on aquatic non-indigenous and cryptogenic species |
Species | Nitellopsis obtusa | |
Date of the first record (?) | 2016 References: Minchin, D., Boelens, R. and Roden, C. (2017) The first record of Nitellopsis obtusa (N. A. Desvaux) J. Groves (Charophyceae, Characeae) in Ireland (H9, H10). Irish Naturalists’ Journal 35: 105-109. Comments: The starry stonewort Nitellopsis obtusa was found in Lough Derg and the Parteen Reservoir on the Lower Shannon River during the summer of 2016. Nitellopsis obtusa has not previously been known to occur in Ireland. |
Recipient region (?) | Country: Ireland LME: 24. Celtic-Biscay Shelf LME sub-region: Celtic seas References: Minchin, D., Boelens, R. and Roden, C. (2017) The first record of Nitellopsis obtusa (N. A. Desvaux) J. Groves (Charophyceae, Characeae) in Ireland (H9, H10). Irish Naturalists’ Journal 35: 105-109. Comments: Sampling to identify the presence and density of N. obtusa in the lower part of Lough Derg downstream to the Parteen Dam and Reservoir. The starry stonewort Nitellopsis obtusa was found in Lough Derg and the Parteen Reservoir on the Lower Shannon River |
|
Source region (?) | Not entered |
Pathway / Vector (?) | Level of certainty: Possible Pathway: Natural spread from neighboring countries Pathway: Natural spread, long distances Pathway: Vessels Vector: Ballast water References: Minchin, D., Boelens, R. and Roden, C. (2017) The first record of Nitellopsis obtusa (N. A. Desvaux) J. Groves (Charophyceae, Characeae) in Ireland (H9, H10). Irish Naturalists’ Journal 35: 105-109. Comments: Several methods of introduction to Lough Derg can be postulated. Recreational craft are known to have come from the Broads region of England where stands of this plant occur. Transmission might have been via the weed trap intakes of the engine cooling water or with fouled anchors, the bulbils being able to survive several days out of water under damp conditions. It is also possible that migrating birds may have carried bulbils or oospores to Ireland. suggest that oospores may be transferred by animals as they can easily attach to feathers as well as fur. Diving birds such as the Tufted Duck (Aythya fuligula (Linnaeus, 1758)) might transport propagules by adhesion, by entanglement or in their gut. |
Habitat type (?) | Lake River References: Minchin, D., Boelens, R. and Roden, C. (2017) The first record of Nitellopsis obtusa (N. A. Desvaux) J. Groves (Charophyceae, Characeae) in Ireland (H9, H10). Irish Naturalists’ Journal 35: 105-109. Comments: N. obtusa generally appeared at depths of 3.2 to 4.7 m in Lough Derg in the region of R696747 but on the western and more sheltered side of the Parteen Reservoir, in the region of R682693, was found at depths from 2.5 m to 4.7 m. In the shallower water in the Parteen Reservoir plants were of a lighter green colour at 2.5 m to 2.8 m than those retrieved in deeper water. |
|
Wave exposure (?) | Not entered | |
Salinity range (?) | Venice system: 1. Limnetic [<0.5psu] |
|
Temperature range (?) | Not entered |
Zonation / Substratum (?) | Not entered | |
Reproductive duration (?) | Not entered | |
Reproductive seasonality (?) | Not entered | |
Migration pattern (?) | Not entered |
Population status (?) | Unknown (Low level of certainty) References: Minchin, D., Boelens, R. and Roden, C. (2017) The first record of Nitellopsis obtusa (N. A. Desvaux) J. Groves (Charophyceae, Characeae) in Ireland (H9, H10). Irish Naturalists’ Journal 35: 105-109. Comments: Dense meadows of N. obtusa occurred below the zone of both native and introduced submerged macrophytes. The stands occupied many hectares over even to gently sloping mud, mud and shell to stones. It is unclear whether this plant is a recent arrival or will have been present for a long period and not recognised. |
|
Species status (?) | Cryptogenic References: Minchin, D., Boelens, R. and Roden, C. (2017) The first record of Nitellopsis obtusa (N. A. Desvaux) J. Groves (Charophyceae, Characeae) in Ireland (H9, H10). Irish Naturalists’ Journal 35: 105-109. Comments: This species does not occur in Britain and is otherwise scarce in Ireland. So it is indeed possible that isolated populations of other charophyte species such as N. obtusa could also exist within the Shannon basin, or elsewhere in Ireland. |
Created by | Dan Minchin, 2022-04-26 |