Category: Species

Neovison vison (Schreber, 1777)

Posted onAuthorManou Pfeiffenschneider

English American mink Status LU: absent.
Lëtzebuergesch Amerikaneschen Näerz1 Status Eur.: established.
Français Vison d’Amérique RA: ISEIA: A0, Alert List. Harmonia+: 0,21
Deutsch Amerikanischer Nerz, Mink Wikipedia: Wikipedia - English - American mink Wikipedia - Français - Vison d'Amérique Wikipedia - Deutsch - Amerikanischer Nerz Wikipedia - Nederlands - Amerikaanse nerts | Wikispecies: Wikispecies - Neovison vison | CABI
Nederlands Amerikaanse nerts Back to the list of vertebrates

Brief description

Mink with catch

A mink with its catch at Litløy fyr, Vesterålenn, Norway.

In both its native and introduced ranges, Neovison vison (Schreber, 1777) is commonly found on brook and riverbanks with dense vegetation, damp forests, reed beds and marshes. Individuals escaping from fur farms have established feral populations in many European countries. Whereas this species has already been observed in the wild several times in Belgium, it has not been reported to have developed viable populations so far. M. vison may severely reduce prey populations (salmonids, amphibians, waterfowl, rodents, etc.) and is a serious threat for red-listed ground-nesting birds. It is also suspected of displacing its relative, the European mink Mustela lutreola, and the European polecat Mustela putorius (Branquart et al. 2013).

The European mink became endangered in the 20th Century, as a result of hunting for the fur trade, habitat loss and invasive alien species, especially the American mink (Wikipedia contributors 2020).

Controversy on listing as IAS of Union concern

The American mink has been the subject of intense discussion, both within the EU Scientific Forum on IAS and the EU Committee on IAS, opposing Northern European countries where breeding for the fur trade is practised versus other EU member countries concerned by the impacts of the invasive species. Scientific reports (e.g. Roy 2017) and publications have emerged from this controversy. Some stakeholders expressed their consternation that the American mink  has not been included in the list (e.g. Swabe 2019).

Status and distribution in Luxembourg

The first documented occurrence of Neovison vison (Schreber, 1777) in Luxembourg dates from March 1993, when a mink was caught in a trap by a hunter in the vicinity of the village of Manternach (Municipality of Manternach). A second record dates back to 2013 (Schley & Herr 2019: 62), when the carcass of a sick animal was found in a forest near Esch-sur-Alzette and sent to the Nature and Forest Administration (Schley 2020).

It is not known whether there is an established population of American mink in Luxembourg (Schley 2001).

There is no distribution map available because no data has been entered into the Recorder-Lux database so far (MNHNL, iNaturalist & GBIF 2019).

Risk assessment

ISEIA protocol

A0 (3+3+3+2) = Alert List (Ries et al. 2014: 199).

Harmonia+ protocol

Overall risk score 0,21 = (Overall Invasion score 0,54 x Overall Impact score 0,39) (evaluated by Sandra Cellina, Jan Herr and Manou Pfeiffenschneider).

0,54Invasion
0,39Impact
0,21Risk

Worldwide distribution

Bibliography

  • Branquart, E., M. D’aes, B. Manet, G. Motte, V. Schockert, J. Stuyck & K. Van Den Berge, 2013. Harmonia database: Mustela vison (Schreber, 1777). Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-24]
  • CABI, 2014. Neovison vison (Schreber, 1777) [text by ISSG, update by Santiago Palazón]. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-02-04]
  • MNHNL, iNaturalist & GBIF, 2019. MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-10-24]
  • Naturverwaltung (ed.), 2013. Jagbare Wildtierarten Luxemburgs. 96 pp.
  • Pir, J.B. & L. Schley, 2015. Développement des connaissances sur la répartition et l’écologie des mammifères au Luxembourg entre 1990 et 2015. Bull. Soc. Nat. luxemb. 116: 437-455.
  • Ries, C., M. Pfeiffenschneider, Engel, E., J.-C. Heidt & M. Lauff, 2014. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of vertebrates in Luxembourg. Bull. Soc. Nat. luxemb. 115: 195-201. [PDF 247 KB]
  • Roy, S. 2017. Information on measures and related costs in relation to species considered for inclusion on the Union list: Neovison vison. Technical note prepared by IUCN for the European Commission.
  • Schley, L., 2001. First Record of the American Mink Mustela vison (Mammalia, Mustelidae) in Luxembourg. Bull. Soc. Nat. luxemb. 102: 45-48. [PDF 215 Kb]
  • Schley, L., 2020. Personal communication by phone to C. Ries on 2020-02-04.
  • Schley, L., C. Schanck, M. Schaul & C. Sinner, 2001. Neubürger und Heimkehrer unter den Wildtieren Luxemburgs. Beiträge zur Jagd- und Wildforschung 26: 141-154.
  • Schley, L. & J. Herr, 2019. Säugetiere Luxemburgs. Hrsg.: natur&ëmwelt a.s.b.l., Ministère du développement durable et des infrastructures, Administration de la nature et des forêts. 219 S. ISBN 978-2-9199511-0-9 [French edition: Les mammifères du Luxembourg, ISBN 978-2-9199511-2-3]
  • Swabe, J. 2019. Feedback from: Humane Society International/Europe (Netherlands) on the Updated list of invasive non-native species in the EU. Feedback reference F461527. URL: https://ec.europa.eu/info/law/better-regulation/initiatives/ares-2019-1565888/feedback/F461527_en?p_id=4101650
  • Wikipedia contributors, 2020. ‘European mink’, Wikipedia, The Free Encyclopedia. URL: https://en.wikipedia.org/wiki/European_mink#Competition_with_the_American_Mink_and_disease [accessed 2020-02-05]

 Page content last updated on 2024-03-13. Last proofread by Caroline Grounds on 2019-11-28.

  1. Näerz: cf. Wörterbuchkommission (Hrsg.), 1987. Luxemburger Wörterbuch. 5 Bd. Im Auftrag der Grossherzoglichen Luxemburgischen Regierung. Linden, Luxemburg.[↩]

Myocastor coypus (Molina, 1782)

Posted onAuthorManou Pfeiffenschneider

English Coypu Status LU: casual. 1st record: 1954.
Lëtzebuergesch Biwerrat Status Eur.: established. IAS of Union concern (2016).
Français Ragondin RA: ISEIA: A1, Black List. Harmonia+: 0,33
Deutsch Nutria Wikipedia: Wikipedia - English - Coypu Wikipedia - Français - Ragondin Wikipedia - Deutsch - Nutria Wikipedia - Nederlands - Beverrat | Wikispecies: Wikispecies - Myocastor coypus | CABI
Nederlands Beverrat Back to the list of vertebrates

Brief description

Myocastor coypus 02

Nutria, river Ljubljanica, Slovenia, January 2011.

Myocastor coypus (Molina, 1782) is a large, herbivorous, semiaquatic rodent. The coypu lives in burrows alongside stretches of water, and feeds on river plant stems. Originally native to subtropical and temperate South America, it has since been introduced to North America, Europe, Asia, and Africa, primarily by fur farmers (Wikipedia contributors 2019).

Overgrazing by nutria causes the local extinction of aquatic plants and the destruction of reedbeds and fish nursery areas. Due to its burrowing activity, it degrades river banks and affects river flow. Rare marshbirds are affected by nest destruction, egg predation or habitat destruction. Nutria could also act as a reservoir for different pathologies and cause damage to agriculture. Nutria is included in the appendix under the recommendation no 77 of the Council of Europe as a species which has proved to be a threat to biological diversity and for which eradication is strongly recommended (Branquart et al. 2013).

IAS of Union concern

In 2016, Myocastor coypus (Molina, 1782) was added to the list of invasive alien species of Union concern (Anonymous 2016) which implies that member states shall take all necessary steps to prevent it’s unintentional introduction or spread.

Status and distribution in Luxembourg

Records of Myocastor coypus Molina, 1782 in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 2025-12-18.

Myocastor coypus was first documented in Luxembourg in February 1954 near the Alzette river in Hunsdorf, Municipality of Lorentzweiler (Heuertz 1957: 50).

A few years ago, it was only observed sporadically in Luxembourg and could not manage to establish (Schley & Herr 2009: 170). In 2024, already 96 observations have been documented in the national database , two thirds of them since 2020 (MNHNL, iNaturalist & GBIF 2024) .

On 19th September 2017, a forester captured a coypu in Osweiler (commune of Rosport, eastern Luxembourg) and put it to sleep. This detection of an IAS of Union concern (Anonymous 2016) was notified to the Luxembourg authorities on 26 September 2017 and an Eradication Measure Set was also submitted on 26 September 2017, pursuant to Article 17(1) of R. 1143/2014 (Anonymous 2014).

Since then, the species was observed on regular basis in Luxembourg. It has to be considered as established at least in the Haff Réimech area. Because of its occurrence in the bordering regions of France (Chiers, Moselle) and Germany (Saar), it is likely that the species will continue to populate national watercourses (Becker-Krüll & Schaefer 2013).

Management

Action plan

An action plan for the species has been published in 2020:

→ Finalised Action Plan for Myocastor coypus (De Sousa 2020)

Risk assessment

ISEIA protocol

A1 (3+3+2+3) = Black List, reassessed on 25 October 2019 by C. Ries & M. Pfeiffenschneider. First assessed as C0 (3+2+1+1) (Ries et al. 2014: 199).

Harmonia+ protocol

Overall risk score 0,33 = (Overall Invasion score 0,48 x Overall Impact score 0,67) (evaluated by Sandra Cellina, Jan Herr and Manou Pfeiffenschneider).

0,48Invasion
0,67Impact
0,33Risk

Worldwide distribution

Fact sheet

PDF fact sheet of the Nature and Forestry Administration: FR | DE

Bibliography

  • Anonymous, 2014. Regulation (EU) No 1143/2014 of the European Parliament and of the Council of 22 October 2014 on the prevention and management of the introduction and spread of invasive alien species. Official Journal of the European Union 4.11.2014 L 317: 35-55.
  • Anonymous, 2016. Commission implementing regulation (EU) 2016/1141 of 13 July 2016 adopting a list of invasive alien species of Union concern pursuant to Regulation (EU) No 1143/2014 of the European Parliament and of the Council. Official Journal of the European Union L 189: 4-5.
  • Becker-Krüll, L. & P. Schaefer, 2013. Jagdbare Wildtierarten Luxemburgs. Administration de la nature et des forêts, Luxembourg, 96 pp.
  • Branquart, E., M. D’aes, B. Manet, G. Motte, V. Schockert & J. Stuyck, 2013. Harmonia database: . Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-25]
  • CABI, 2008. Myocastor coypus (Molina, 1782) [original text by Dr. Sandro Bertolino & IUCN/SSC]. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2019-11-22]
  • De Sousa, T., 2020. Plan d’action pour espèces exotiques envahissantes au Grand-Duché de Luxembourg: le Ragondin, Myocastor coypus (Molina, 1792). Version 2020-09-04. Administration de la nature et des forêts, Luxembourg. 21 pp.
  • Heuertz, M., 1957. Premières captures de rats musqués (Ondatra zibethicus L.) au grand-duché de Luxembourg. Archives de la section des sciences de l’Institut grand-ducal N.S. 24: 41-51.
  • MNHNL, 2000-. Myocastor coypus (Molina, 1782) in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2020-02-04]
  • MNHNL, iNaturalist & GBIF, 2019. Myocastor coypus (Molina, 1782) in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2020-02-04]
  • Pir, J.B. & L. Schley, 2015. Développement des connaissances sur la répartition et l’écologie des mammifères au Luxembourg entre 1990 et 2015. Bull. Soc. Nat. luxemb. 116: 437-455.
  • Ries, C., M. Pfeiffenschneider, Engel, E., J.-C. Heidt & M. Lauff, 2014. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of vertebrates in Luxembourg. Bull. Soc. Nat. luxemb. 115: 195-201. [PDF 247 KB]
  • Schley, L., C. Schanck, M. Schaul & C. Sinner, 2001. Neubürger und Heimkehrer unter den Wildtieren Luxemburgs. Beiträge zur Jagd- und Wildforschung 26: 141-154.
  • Schley, L. & J. Herr, 2019. Säugetiere Luxemburgs. Hrsg.: natur&ëmwelt a.s.b.l., Ministère du développement durable et des infrastructures, Administration de la nature et des forêts. 219 S. ISBN 978-2-9199511-0-9 [French edition: Les mammifères du Luxembourg, ISBN 978-2-9199511-2-3]
  • Wikipedia contributors, 2019. ‘Coypu’, Wikipedia, The Free Encyclopedia, 17 October 2019. URL: https://en.wikipedia.org/w/index.php?title=Coypu&oldid=921725301 [accessed 25 October 2019]

 Page content last updated on 2024-07-31. Last proofread by Caroline Grounds on 2019-11-27.

Senecio inaequidens DC.

Posted onAuthorDr. Christian Ries

English Narrow-leaved ragwort Status LU: established. 1st record: LU & ITW 1988.
Lëtzebuergesch Schmuelt Kräizkräitchen Status Eur.: established. 1st record: DE 1889.1
Français Séneçon du Cap RA: ISEIA: B2, Watch List. Harmonia+: 0,29.
Deutsch Schmalblättriges Greiskraut Wikipedia: Wikipedia - English - Narrow-leaved ragwort Wikipedia - Français - Séneçon du Cap Wikipedia - Deutsch - Schmalblättriges Greiskraut Wikipedia - Nederlands - Bezemkruiskruid | Wikispecies: Wikispecies - Senecio inaequidens | CABI
Nederlands Bezemkruiskruid Back to the list of neophytes

Brief description

Senecio inaequidens

Kristian Peters @ Wikimedia Commons

Senecio inaequidens DC. mainly thrives in ruderal and disturbed areas. It may also be found in rock outcrops, open grasslands and sand dunes. Minute achenes (3 mm) are mainly dispersed by wind, but also by water and animals, travelling long distances. Senecio inaequidens does not demonstrably pose a threat to indigenous species or plant communities at present in western Europe. The plant is toxic for livestock (Branquart et al. 2010).

As a plant of the southern hemisphere, it tends to flower particularly in autumn (springtime in its region of origin) and it is only the first serious frosts that make its beautiful light-yellow flower heads disappear, carried on stems lined with linear leaves (Reichling 1990: 67).

Status and distribution in Luxembourg

Records of Senecio inaequidens DC. in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 2025-12-18.

Senecio inaequidens DC. was first observed in Luxembourg in the wild by Ed Melchior on 1988-07-31 on a slag heap in Differdange (Reichling 1990: 67; MNHNL 2000-). This record was published with the following annotations by Léopold Reichling: “A South African species, new to our country. It has become naturalised in some regions of southern and western Europe, closer to home, particularly in Belgium (especially the Liège region) (e.g. Van Rompaey & Delvosalle, 1979, map 1040: Delvosalle & al. 1979 and in the NW of Germany (e. g. Kuhbier, 1977). Given the momentum with which it often invades newly conquered lands, it can be expected to spread to the slag heaps and quarry bottoms of the Mining Basin. As a plant of the southern hemisphere, it tends to flower mainly in the autumn (springtime in its native land) and it is only the first serious frosts that make its beautiful light-yellow flower heads disappear, carried on stems lined with linear leaves with an embracing base” (Reichling 1990: 67; see here for the cited references).

In 2008 and 2009, isolated plants were observed in the northern part of Luxembourg (Esch/Sûre, Harlange). In 2012, only 14 observations were documented in the Recorder-Lux database (MNHNL 2000-). In 2014 a survey of the species along highways increased the number of records (Frankenberg & Gräser 2014). Currently, 164 records are accessible through the MNHNL-mdata portal (MNHNL, iNaturalist & GBIF 2021).

But while the first populations of the plant were documented in industrial areas in the south of Luxembourg, it took the species only a few years to spread to Luxembourg City as well as to the German and Belgian borders, using the motorway network as a dispersal route. A study from 2014 showed that by then the species had populated almost the entire motorway network of Luxembourg (Frankenberg & Gräser 2014).

The species is already widespread in the south of the country, mainly along the main roads, but it is also expanding in the central and northern parts of the country and is increasingly being observed at stations far from any roadside (Krippel et al. 2020: 47).

The species appeared spontaneously in 2020 and 2021 at various locations along the course of the water pipe as well as in August 2021 in the construction site of the new treatment plant of the Syndicat des eaux du barrage d’Esch-sur-Sûre (SEBES) (Wolff & Krippel 2022: 7).

The species continues to expand its range and will probably have negative impacts on biodiversity as soon as it spreads from motorways and roads into grassland, pastures and rock ecosystems.

This species, native to South Africa, is naturalised in southern and western Europe. Common to rare, with strong expansion in the wild. Roadsides, railway ballast, wastelands, slag heaps, quarry screes, lawns. Originally, this species was mainly naturalised in the eastern Mosan area (Vesdre valley and Meuse valley around Liège) and in the surroundings of Calais. It then spread (especially from the 1980s onwards), often proving to be a very invasive weed. It is now found in a large part of the region, where it is still growing (Lambinon & Verloove 2012: 739).

Risk assessment

ISEIA protocol

B2 (3+2+2+3) = Watch List (Ries et al. 2013: 19).

Harmonia+ protocol

Overall risk score 0,29 = (Overall Invasion score 0,76 x Overall Impact score 0,38) (Ries et al. 2020).

0,76Invasion
0,38Impact
0,29Risk

Worldwide distribution

Bibliography

  • Branquart, E., S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove, 2010. Harmonia database: Senecio inaequidens DC. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-15]
  • CABI, 2019. Senecio inaequidens. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-03-04]
  • Colling, G. et L. Reichling, 1996. Notes floristiques 1994-1995. Bull. Soc. Nat. luxemb. 97: 25-38. [PDF 596 KB]
  • Colling , G. & Y. Krippel, 2001. Notes floristiques. Observations faites au Luxembourg (1998-1999). Bull. Soc. Nat. luxemb. 101: 33-48. [PDF 331 Kb]
  • Frankenberg, T. & P. Gräser, 2014. Vorkommen des Schmalblättrigen Greiskrauts (Senecio inaequidens DC.) in Luxemburg, Erfassung der aktuellen Verbreitung der Art entlang der Autobahnen und Autobahnzubringer. Unveröff. Studie des Büros EFOR-ERSA im Auftrag Nationalmuseums für Naturgeschichte, Oktober 2014. 6 S. + Anhang [PDF-Bericht, PDF-Übersichtskarte].
  • Krippel, Y. & G. Colling, 2008. Notes floristiques. Observations faites au Luxembourg (2006-2007). Bull. Soc. Nat. luxemb. 109: 59-76. [PDF 549 KB]
  • Krippel, Y. & G. Colling, 2010. Notes floristiques. Observations faites au Luxembourg (2008- 2009). Bull. Soc. Nat. luxemb. 111: 11-32. [PDF 209 KB]
  • Krippel, Y. & G. Colling, 2012. Notes floristiques. Observations faites au Luxembourg (2010-2011). Bull. Soc. Nat. luxemb. 113: 67-82. [PDF 579 KB]
  • Krippel, Y. & G. Colling, 2014. Notes floristiques. Observations faites au Luxembourg (2012-2013). Bull. Soc. Nat. luxemb. 115: 109-124. [PDF 893 KB]
  • Krippel, Y., T. Helminger & G. Colling, 2020. Notes floristiques. Observations faites au Luxembourg (2018-2019). Bulletin Soc. Nat. luxemb. 122 : 29-55. [PDF 132 KB]
  • Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
  • MNHNL, 2000-. Senecio inaequidens DC. in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-10-15]
  • MNHNL, iNaturalist & GBIF, 2021. Senecio inaequidens DC. in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-10-15]
  • Reichling, L., 1990. Observations floristiques au Luxembourg 1980-1989. Bull. Soc. Nat. luxemb. 90: 55-70. [PDF 808 KB]
  • Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
  • Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
  • Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]
  • Wolff, J.-P. & Y. Krippel, 2022. Epilobium brachycarpum C. Presl (Onagraceae), une nouvelle espèce pour la flore du Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 124 : 3-8. [PDF 5,13 MB]

 Page content last updated on 2022-02-22. Last proofread by Caroline Grounds on 2019-11-21.

  1. Cf. CABI 2019.[↩]

Elodea canadensis Michx.

Posted onAuthorDr. Christian Ries

English Canadian waterweed, pondweed Status LU: established. 1st record: LU & ITW ~1875
Lëtzebuergesch Kanadesch Waasserpescht Status Eur.: established. 1st record: IE 1836.
Français Élodée du Canada RA: ISEIA: A3 – Black List. Harmonia+: 0,46
Deutsch Kanadische Wasserpest Wikipedia: Wikipedia - English - Canadian waterweed Wikipedia - Français - Élodée du Canada Wikipedia - Deutsch - Kanadische Wasserpest Wikipedia - Nederlands - Brede waterpest | Wikispecies: Wikispecies - Elodea canadensis | CABI
Nederlands Brede waterpest Back to the list of neophytes

Brief description

Elodea canadensis Michx. is an aquatic plant native to North America that thrives in a variety of freshwater habitats, from still to slow-flowing systems and from very shallow to deep waters. It is most frequent in clear, nutrient-rich and alkaline waters. Elodea aggressively invaded the waterways of Europe in the 19th Century (Branquart et al. 2010).

Status and distribution in Luxembourg

Records of Elodea canadensis Michx. in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 2025-12-18.

Elodea canadensis Michx. was introduced around 1875 to the Grand Duchy of Luxembourg in 2 ponds between Itzig, Contern and Scheidhof (Fischer 1882: 122). In the following years, it was found in Imbringen (1883), Meysembourg (1886), Schrassig (1902), Diekirch (1906), Birelergrund (1908) and Bissen (1909). Sunnen (1918: 10) mentions the Canadian pondweed in Brasseur’s pond, located on the Outer Ring of Luxembourg’s Old Town.

The Canadian waterweed has become quite common in our regions and can be observed in both standing and river waters (Diederich 1984: 38).

The oldest herbarium specimen in the Museum was collected in 1883 by Jean Feltgen (1833-1904) in standing water in the meadows of Imbringen (Specimen № 629a MNHNL 2000-).

Until 1909 the species had not been observed in the Ardennes (Oesling) (Robert 1910: 15).

By now the Canadian waterweed is widely spread throughout the country (MNHNL, iNaturalist & GBIF 2019).

The North American plant Elodea canadensis was introduced to Europe around 1835 and quickly invaded the fresh waters of much of the continent. However, this expansion seems to have stopped or even reversed today, and is tending to be replaced by Elodea nuttallii (Planch.) H. St. John (Lambinon & Verloove 2012: 790, 791).

Risk assessment

ISEIA protocol

A3 (3+3+3+3) = Black List (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,46 = (Overall Invasion score 0,77 x Overall Impact score 0,60) (Ries et al. 2020).

0,77Invasion
0,60Impact
0,46Risk

Worldwide distribution

Bibliography

  • Branquart, E., I. Stiers, L. Triest, S. Vanderhoeven, W. Van Landuyt, F. Van Rossum, F. Verloove, 2010. Harmonia database: Elodea canadensis Michx.. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-09]
  • CABI, 2019. Elodea canadensis. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-02-28]
  • Diederich, P., 1984. Les monocotylédones aquatiques (excl. Potamogeton s.l.) du Grand-Duché de Luxembourg. Dumortiera 29-30: 34-41. [PDF 5 MB].
  • Fischer, M.-E., 1882. Plantes phanérogames nouvelles ou rares de la flore luxembourgeoise. Recueil des mémoires et des travaux publiés par la Société de botanique du grand-duché de Luxembourg 6-8: 116-124.
  • Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
  • MNHNL, 2000-. Elodea canadensis Michx. in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-09-05]
  • MNHNL, iNaturalist & GBIF, 2019. Elodea canadensis Michx. in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-09-06]
  • Oly, M., 2022. Kartierung invasiver gebietsfremder Wasserpflanzen im Großherzotum Luxemburg, Untersuchungen zur Verbreitung von invasiven gebietsfremden Wasserpflanzen in einer beispielhaften Auswahl an Stillgewässern, Musée national d’histoire naturelle, Luxembourg. 117 pp. 
  • Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
  • Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
  • Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]
  • Robert, J., 1910. Beiträge zur Flora des Grossherzogtums Luxemburg. lnst. G.-D. Lux., Sect. Sc. natur., phvs., math., Arch. trimestr. n.s. V: 1-35. Luxembourg: Imprimerie de la Cour Victor-Buck.
  • Sunnen, M., 1918. Die Stechmückenplage in Luxemburg und Umgebung. P. Worré-Mertens, Luxembourg, 24 p. [PDF 80 MB]

 Page content last updated on 2023-08-17. Last proofread by Caroline Grounds on 2019-11-14.

Hydrocotyle ranunculoides L.f.

Posted onAuthorDr. Christian Ries

English Floating pennywort Status LU: absent. 1st record: n/a.
Lëtzebuergesch Grousse Waassernuebel Status Eur.: established. 1st record: NL, BE, UK 1980s. IAS of EU concern (2016)
Français Hydrocotyle fausse renoncule RA: ISEIA: A0, Alert List. Harmonia+: 0,38.
Deutsch Großer Wassernabel Wikipedia: Wikipedia - English - Floating pennywort Wikipedia - Français - Hydrocotyle fausse renoncule Wikipedia - Nederlands - Grote waternavel Wikispecies: Wikispecies - Hydrocotyle ranunculoides | CABI
Nederlands Grote waternavel Back to the list of neophytes

Brief description

Hydrocotyle ranunculoides L.f. is an aquatic plant that thrives in slow-flowing water bodies, particularly in ditches, canals, lakes and ponds. It prefers eutrophic waters, but it can also colonise marshes and mesotrophic water bodies. The species forms dense interwoven mats of vegetation which can quickly cover the entire water surface. Due to its vigorous growth, this plant causes loss of light and reduction in dissolved oxygen content in the water. As a consequence, the native submerged and water-edge plant species can be outcompeted, and ecosystem functions can be altered (Branquart et al. 2013).

IAS of Union concern

In 2016, Hydrocotyle ranunculoides L.f. was added to the list of invasive alien species of Union concern (Anonymous 2016) which implies that member states shall take all necessary steps to prevent it’s unintentional introduction or spread.

Status and distribution in Luxembourg

Hydrocotyle ranunculoides L.f. has not yet been observed in Luxembourg.

Risk assessment

ISEIA protocol

A0 (2+3+3+3) = Alert List (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,38 = (Overall Invasion score 0,65 x Overall Impact score 0,58) (Ries et al. 2020).

0,65Invasion
0,58Impact
0,38Risk

Worldwide distribution

Ressources

Verloove & Heyneman (2021) have published an identification key allowing to identify the species of Hydrocotyle currently found in Belgium.

Bibliography

  • Anonymous, 2016. Commission implementing regulation (EU) 2016/1141 of 13 July 2016 adopting a list of invasive alien species of Union concern pursuant to Regulation (EU) No 1143/2014 of the European Parliament and of the Council. Official Journal of the European Union L 189: 4-5.
  • Branquart, E., I. Stiers, L. Triest, S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove, 2013. Harmonia database: Hydrocotyle ranunculoides L. f.. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-11-21]
  • CABI, 2019. Hydrocotyle ranunculoides. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-03-02]
  • Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
  • Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]
  • Verloove, F. & G. Heyneman, 2021. A note on some alien species of Hydrocotyle (Araliaceae) in Belgium. Dumortiera 117: 26-29. [PDF]

 Page content last updated on 2021-03-28. Last proofread by Caroline Grounds on 2019-11-18.

Mimulus guttatus DC.

Posted onAuthorDr. Christian Ries

English Monkeyflower Status LU: established. 1st record: LU & ITW 1998.
Lëtzebuergesch Getëppelt Mimekraut Status Eur.: established. 1st record: unkn.
Français Mimule tacheté RA: ISEIA: C1. Harmonia+: 0,16.
Deutsch Gelbe Gauklerblume Wikipedia: Wikipedia - English - Monkeyflower Wikipedia - Français - Mimule tacheté Wikipedia - Deutsch - Gelbe Gauklerblume Wikipedia - Nederlands - Gele maskerbloem | Wikispecies: Wikispecies - Mimulus guttatus | CABI
Nederlands Gele maskerbloem Back to the list of neophytes

Brief description

Mimulus guttatus 5649Mimulus guttatus DC. (Syn.:  Erythranthe guttata (Fisch. DC.) G.L.Nesom) typically grows in disturbed areas around river banks and is rarely found in the adjacent marshes and wet meadows. This plant species colonises gaps within the established vegetation. It can form large patches where tree cover is low and vegetation is dominated by light-demanding, ruderal and small-sized plant species, especially in the upper reaches of streams (Baus et al. 2010).

Status and distribution in Luxembourg

Records of Mimulus guttatus DC. in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 2025-12-18.

The western North American Mimulus guttatus DC. was first documented in Luxembourg by Gérard Schmid on 1998-09-01 near the mill on the right bank of the river Attert in the municipality of Useldange (Colling & Krippel 2001: 42).

In 2019, about 15 plants were discovered near Reimberg in the ruts left by the construction machines of a water pipeline (Krippel et al. 2020: 41).

A large population was found on 10th July 2020 around an artificial garden pond in Simmerschmelz. According to the garden owner, the species was not planted, it suddenly appeared several years ago.

Population of Mimulus guttatus around a pond in Simmerschmelz. Photo: 10 July 2020 by C. Ries.

15 records are accessible through the MNHNL-mdata portal (MNHNL, iNaturalist & GBIF 2020).

Rare to very rare, naturalised; expanding, at least locally, in the wild. Sometimes cultivated for ornamental purposes along watercourses (Lambinon & Verloove 2012: 634).

Risk assessment

ISEIA protocol

C1 (1+2+1+1) (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,16 = (Overall Invasion score 0,71 x Overall Impact score 0,23) (Ries et al. 2020).

0,71Invasion
0,23Impact
0,16Risk

Worldwide distribution

Bibliography

  • Baus, E., E. Branquart, S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove 2010. Harmonia database: Mimulus guttatus DC.. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-14]
  • CABI, 2019. Mimulus guttatus. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-03-02]
  • Colling , G. & Y. Krippel, 2001. Notes floristiques. Observations faites au Luxembourg (1998-1999). Bull. Soc. Nat. luxemb. 101: 33-48. [PDF 331 Kb]
  • Krippel, Y., T. Helminger & G. Colling, 2020. Notes floristiques. Observations faites au Luxembourg (2018-2019). Bulletin Soc. Nat. luxemb. 122 : 29-55. [PDF 132 KB]
  • Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
  • MNHNL, 2000-. Mimulus guttatus DC. in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-10-14]
  • MNHNL, iNaturalist & GBIF, 2020. Mimulus guttatus DC. in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2020-07-20]
  • Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
  • Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
  • Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]

 Page content last updated on 2021-03-04. Last proofread by Caroline Grounds on 2019-11-20.

Rudbeckia laciniata L.

Posted onAuthorDr. Christian Ries

English Coneflower Status LU: established. 1st record: LU & ITW 1887.
Lëtzebuergesch Spléckbliedrege Sonnenhutt Status Eur.: established. 1st record: <1625.1
Français Rudbéckie laciniée RA: ISEIA: C1. Harmonia+: 0,17.
Deutsch Schlitzblättriger Sonnenhut Wikipedia: Wikipedia - English- Coneflower Wikipedia - Deutsch - Schlitzblättriger Sonnenhut Wikipedia - Nederlands - Slipbladige rudbeckia | Wikispecies: Wikispecies - Rudbeckia laciniata | CABI
Nederlands Slipbladige rudbeckia Back to the list of neophytes

Brief description

Slipbladige rudbeckia 20-08-2005 18.25.12Rudbeckia laciniata L. mostly grows in open ruderal and alluvial habitats (e.g. river banks). Seeds may only germinate from bare soil; the low germination and recruitment rates in undisturbed sites reduce plant capacity to colonise natural plant communities. The plant can however form dense and monospecific stands due to vegetative growth (rhizomes). R. laciniata, or coneflower, locally decreases plant species richness and hinders colonisation of open habitats by tree species, especially in riparian areas. The plant is toxic for livestock but also very melliferous (Branquart et al. 2010).

Status and distribution in Luxembourg

Records of Rudbeckia laciniata L. in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 2025-12-18.

Rudbeckia laciniata L. was first mentioned for Luxembourg in the wild in the surroundings of Mersch by Feltgen (1901: 254).

The oldest herbarium specimen of Rudbeckia laciniata L. at the MNHNL was collected on 20 August 1935 by Jos. Witry in gardens in Schifflange (Specimen № 50794, MNHNL 2000-). The next scientific record that we know of was made by Léopold Reichling (1921-2009) on 12th June 1961 near the river Alzette in the municipality of Walferdange (MNHNL 2000-).

Currently, 2 records of coneflower are accessible through the MNHNL-mdata portal (MNHNL, iNaturalist & GBIF 2019).

This melliferous species from North America is naturalised in Europe, especially in central Europe. River and canal banks, river gravel, sometimes wasteland. Sometimes subspontaneous or adventitious. Sometimes cultivated for garden ornament (Lambinon & Verloove 2012: 719).

The species is comparable to Helianthus tuberosus in its ecology but is much less common in Luxembourg.

Risk assessment

ISEIA protocol

C1 (2+2+2+2) (Ries et al. 2013: 19).

Harmonia+ protocol

Overall risk score 0,17 = (Overall Invasion score 0,51 x Overall Impact score 0,33) (Ries et al. 2020).

0,51Invasion
0,33Impact
0,17Risk

Worldwide distribution

Bibliography

  • Branquart, E., S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove, 2010. Harmonia database: Rudbeckia laciniata L.. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-15]
  • CABI, 2019. Rudbeckia laciniata. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-03-02]
  • Feltgen, E., 1901. Mersch sowie nächste und weitere Umgebung, zum Gebrauch für Naturfreunde. Bulletin de la Société des naturalistes luxembourgeois 11: 246-277.
  • Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
  • MNHNL, 2000-. Rudbeckia laciniata L. in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-10-15]
  • MNHNL, iNaturalist & GBIF, 2019. Rudbeckia laciniata L. in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-10-15]
  • Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
  • Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
  • Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]

 Page content last updated on 2021-03-11. Last proofread by Caroline Grounds on 2019-11-21.

  1. Cf. CABI 2019.[↩]

Claytonia perfoliata Donn ex Willd.

Posted onAuthorDr. Christian Ries

English Spring beauty Status LU: casual. 1st record: LU & ITW 1988.
Lëtzebuergesch Wanter-Portulak Status Eur.: established.
Français Claytone de Cuba RA: ISEIA: C1. Harmonia+: 0,04
Deutsch Gewöhnliches Tellerkraut, Winterportulak Wikipedia: Wikipedia - English - Spring beauty Wikipedia - Français - Claytone de Cuba Wikipedia - Deutsch - Gewöhnliches Tellerkraut Wikipedia - Nederlands - Winterpostelein | Wikispecies: Wikispecies - Claytonia perfoliata
Nederlands Winterpostelein Back to the list of neophytes

Brief description

Claytonia perfoliata — Flora Batava — Volume v14

Claytonia perfoliata — Flora Batava, 1872

Claytonia perfoliata Donn ex Willd. (syn. Montia perfoliata), also known as miner’s lettuce or winter purslane, is a fleshy, herbaceous, annual plant native to the western mountainous and coastal regions of Northern America. The common name of miner’s lettuce refers to how the plant was used by miners during the California Gold Rush, who ate it to prevent scurvy. It has been widely naturalised in western Europe, after being introduced there in the eighteenth century, possibly by the naturalist Archibald Menzies, who brought it to Kew Gardens in London in 1794 (Wikipedia contributors, 2019).

Status and distribution in Luxembourg

Records of Claytonia perfoliata Donn ex Willd. in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 2025-12-18.

The oldest specimen in the herbarium of the Museum dates from 1866 and was collected in the Brussels district Uccle, Belgium, but it mentions no exact date nor a collectors name (Specimen № 2515, MNHNL 2000-).

In Luxembourg, Claytonia perfoliata Donn ex Willd. was first observed by Paul Diederich in the spring of 1988 en masse in a nursery on the plateau south-east of Lorentzweiler (LUREF 79436 E / 83775 N1). At the same time, a few individuals were found under a tree planted in front of building n°17 on Avenue Guillaume in Luxembourg City (Reichling 1990: 58). In spring 1989, the plant was observed by Jean-Marie Mangen in an ornamental plantation at Geessekneppchen in Luxembourg City (Reichling 1990: 59). In Summer 1989, it was next observed by Kariger: 1989-06-25 on flower beds of the grounds around the City Theatre on Limpertsberg, Luxembourg City, as weed in a plant association belonging to the Digitario-Setarienion; 1989-06-10 also as a weed in flower pots at the Finsterthal campsite (Kariger 1990: 76).

On May 16, 2004, Yves Krippel and Tania Wambach observed the species growing on a surface of ± 10 m2 in the woods and in a lawn on the edge of the mini-golf of the camping Maartboesch in Berdorf (Krippel et al. 2006).

Currently, 10 records of the species in Luxembourg are accessible through the MNHNL-mdata portal (MNHNL, iNaturalist & GBIF 2021).

Once grown in gardens as a vegetable plant (Lambinon & Verloove 2012: 149).

Risk assessment

ISEIA protocol

C1 (1+1+1+1) (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,04 = (Overall Invasion score 0,46 x Overall Impact score 0,08) (Ries et al. 2020).

0,46Invasion
0,08Impact
0,04Risk

Bibliography

  • Kariger, J.-J., 1990. Auf der Suche nach Seltenheiten und verschwundenem 1970-1989. Bericht und Auswahl floristischer Tätigkeit ergänzt durch ökologische Betrachtungen. Bulletin de la Société des naturalistes luxembourgeois 90: 71-101.
  • Krippel, Y. & G. Colling, 2006. Notes floristiques. Observations faites au Luxembourg (2004-2005). Bull. Soc. Nat. luxemb. 107: 89-103. [PDF 288 Kb]
  • Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
  • MNHNL, 2000-. Claytonia perfoliata Donn ex Willd. in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-09-05]
  • MNHNL, iNaturalist & GBIF, 2019. Claytonia perfoliata Donn ex Willd. in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2021-01-12]
  • Reichling, L., 1990. Observations floristiques au Luxembourg 1980-1989. Bull. Soc. Nat. luxemb. 90: 55-70. [PDF 808 KB]
  • Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
  • Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
  • Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]
  • Wikipedia contributors, 2019. Claytonia perfoliata Donn ex Willd. in Wikipedia, The Free Encyclopedia, 24 September 2019. URL: https://en.wikipedia.org/w/index.php?title=Claytonia_perfoliata&oldid=917517303 [accessed 2 October 2019]

 Page content last updated on 2021-03-02. Last proofread by Caroline Grounds on 2019-11-14.

  1. Source: Diederich, P.,  2019. Personal communication by email to C. Ries on 2019-10-28.[↩]

Crassula helmsii (Kirk) Cockayne

Posted onAuthorDr. Christian Ries

English New Zealand pigmyweed Status LU: established. 1st record: LU & ITW 2020.
Lëtzebuergesch Weier-Déckblat Status Eur.: established. 1st record: UK 1911.
Français Crassule des étangs RA: ISEIA: B1 – Watch List. Harmonia+: 0,44
Deutsch Nadelkraut Wikipedia: Wikipedia - English - New Zealand pigmyweed Wikipedia - Deutsch - Nadelkraut Wikipedia - Nederlands - Watercrassula | Wikispecies: Wikispecies - Crassula helmsii | CABI
Nederlands Watercrassula Back to the list of neophytes

Brief description

Crassula helmsii

2011, Pilley, England, UK

Crassula helmsii (Kirk) Cockayne, native to New Zealand and Australia, is an aquatic or semi-terrestrial plant that colonises a wide variety of freshwater habitats. The plant’s ability to grow from stem fragments enables it to easily spread from ponds and ornamental pools into the wild. Waterfowl, mammals, downstream movement and flooding all play an important role in plant dissemination. New Zealand pigmyweed can cause major environmental problems in freshwater habitats. It forms dense vegetation mats that deplete oxygen, outcompete native species and may affect the breeding success and survival of threatened aquatic plants and amphibians. Mats choke ponds and drainage ditches, impede water flow and adversely affect recreational activities. In rivers, flow behaviour may change when the plant occurs in masses (Branquart et al. 2013).

Status and distribution in Luxembourg

Records of Crassula helmsii (Kirk) Cockayne in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 2025-12-18.

Crassula helmsii (Kirk) Cockayne was first recorded in the wild by Jean-Paul Wolff on 2020-07-23 as part of a SICONA monitoring project, growing all over a pond in Moukebrill near Grass (MNHNL, 2000-, Wolff 2020).
First reported in Belgium in 1983, this species experienced a strong expansion about 15 years later and will probably be found in other parts of the territory of the Flora. The plant is highly variable depending on whether it grows in water (aquatic phenotype) or on the banks of more or less dry ponds (terrestrial phenotype) (Lambinon & Verloove 2012).

Crassula helmsii in Moukebrill near Grass. Photo: Jean-Paul Wolff, 2020-07-23.
Crassula helmsii in Moukebrill near Grass. Photo: Jean-Paul Wolff, 2020-07-23.

Management

Our neighbouring countries have already gained experience with the management of the species and made it available in publications: Dortel & Dutartre 2018, Delbart et al. 2011, Ewald 2014, van der Loop et al. 2018.

Risk assessment

ISEIA protocol

Following its discovery in Luxembourg in July 2020, the species has been reassessed on 24 July 2020 to B1 (2+3+2+3) = Watch List by Christian Ries and Yves Krippel. Assessment before the appearance of the species in Luxembourg: B0 (2+3+2+3) = Alert List (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,44 = (Overall Invasion score 0,76 x Overall Impact score 0,57) (Ries et al. 2020).

0,76Invasion
0,57Impact
0,44Risk

Worldwide distribution

Bibliography

  • Branquart, E., I. Stiers, L. Triest, S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove, 2013. Harmonia database: . Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2020-02-28]
  • CABI, 2019. Crassula helmsii. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2020-02-28]
  • Dortel, F. & A. Dutartre, 2018. La Crassule de Helms (Crassula helmsii Cockayne, 1907) : Fiche d’alerte détaillée, première analyse des risques, possibilités de régulation et mesures de biosécurité. 23 p. [PDF]
  • Delbart, E., A. Monty & G. Mahy, 2011. Gestion de Crassula helmsii en Belgique plus difficile qu’il n’y paraı̂t? Bulletin OEPP/EPPO Bulletin 41: 226–231. [PDF]
  • Ewald, N.C., 2014. Crassula helmsii in the New Forest – a report on the status, spread and impact of this non-native invasive plant, and the efficacy of novel control techniques following a 2 year trial. Partner Annex Report for RINSE prepared on behalf of the New Forest Non-Native Plants Project. Freshwater Habitats Trust, Oxford. [PDF]
  • Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
  • MNHNL, 2000-. Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. National Museum of Natural History, Luxembourg. Crassula helmsii (Kirk) Cockayne observed on 2020-07-23, occurrence ID MNHNL00000005TLE, via https://mdata.mnhn.lu [accessed 2021-02-22].
  • MNHNL, iNaturalist & GBIF, 2020. in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2020-02-28]
  • Oly, M., 2022. Kartierung invasiver gebietsfremder Wasserpflanzen im Großherzotum Luxemburg, Untersuchungen zur Verbreitung von invasiven gebietsfremden Wasserpflanzen in einer beispielhaften Auswahl an Stillgewässern, Musée national d’histoire naturelle, Luxembourg. 117 pp. 
  • Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
  • Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
  • Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]
  • van der Loop, J.M.M., L. de Hoop, H.H. van Kleef & R.S.E.W. Leuven, 2018. Effectiveness of eradication measures for the invasive Australian swamp stonecrop Crassula helmsii. Management of Biological Invasions (2018) Volume 9, Issue 3: 343–355. DOI: https://doi.org/10.3391/mbi.2018.9.3.16 [PDF]
  • Wolff, J.-P., 2020. Crassula helmsii observation at iNaturalist. URL: https://www.inaturalist.org/observations/54040409 [accessed 2020.07.24].

 Page content last updated on 2025-10-02.

Duchesnea indica (Andrews) Th.Wolf

Posted onAuthorDr. Christian Ries

English Yellow-flowered Strawberry Status LU: established. 1st record: LU <2007, ITW 2008.
Lëtzebuergesch Schäinäerdbier Status Eur.: established. 1st record: <1850.
Français Fraisier des Indes RA: ISEIA: C1. Harmonia+: 0,05
Deutsch Scheinerdbeere Wikipedia: Wikipedia - English - Yellow-flowered Strawberry Wikipedia - Français - Fraisier des Indes Wikipedia - Deutsch - Scheinerdbeere Wikipedia - Nederlands - Schijnaardbei | Wikispecies: Wikispecies - Duchesnea indica
Nederlands Schijnaardbei Back to the list of neophytes

Brief description

Duchesnea indica (Andrews) Th.Wolf is a plant native to SE-Asia that prefers relatively moist and shaded habitats. It grows preferentially on soils with high nitrogen supply and benefits from increasing anthropogenic nitrogen deposition. It occurs in woods, grasslands and urban parks. Seeds are known to be dispersed by birds (Branquart et al. 2012).

Status and distribution in Luxembourg

Records of Duchesnea indica (Andrews) Th.Wolf in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 2025-12-18.

In Luxembourg, Duchesnea indica (Andrews) Th.Wolf was first planted in the Mediterranean Garden in Schebsange before 2007 (Moes G. in litt.). The species was first documented in the wild on 2008-10-31 by Florian Hans at Ennëschte Bësch in the municipality of Bertrange (MNHNL 2000-; Krippel et al. 2010). It occurred on about 2 m² along the roadside and a recently cleared softwood plot, together with Alliaria petiolata, Ranunculus repens, Scrophularia nodosa and Urtica dioica.

There are five records of the species in the MNHNL-mdata online portal, four from Luxembourg City and one from Schengen (MNHNL, iNaturalist & GBIF 2019).

The Yellow-flowered Strawberry is cultivated for ornamental purposes in parks and gardens, it is subspontaneous or naturalised in former parks, garden surroundings, forest roads and cemeteries. This rather rare to rare species is expanding, especially in the western part of the environment (Lambinon & Verloove 2012: 351).

Duchesnea indica was planted in 2002 in the Reimerwee park of the Kirchberg arboretum in Luxembourg City. This population has established itself well (Helminger 2018).

Risk assessment

ISEIA protocol

C1 (2+1+2+1) (Ries et al. 2013: 18).

Harmonia+ protocol

Overall risk score 0,05 = (Overall Invasion score 0,59 x Overall Impact score 0,09) (Ries et al. 2020).

0,59Invasion
0,09Impact
0,05Risk

Worldwide distribution

Bibliography

  • Branquart, E., P. Dupriez, S. Vanderhoeven, W. Van Landuyt, F. Van Rossum, F. Verloove, 2012. Harmonia database: Duchesnea indica (Andrews) Th.Wolf. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-10-09]
  • GBIF 2020. Duchesnea indica (Andr.) Focke in GBIF Secretariat (2019). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2020-02-28.
  • Helminger, T., 2018. Personal communication to Lucie Lentz during summer 2018.
  • Krippel, Y. & G. Colling, 2010. Notes floristiques. Observations faites au Luxembourg (2008- 2009). Bull. Soc. Nat. luxemb. 111: 11-32. [PDF 209 KB]
  • Lambinon J. & F. Verloove, 2012. Nouvelle flore de la Belgique, du grand-duché de Luxembourg, du Nord de la France et des régions voisines. Sixième édition. Avec la collaboration de L. Delvosalle, B. Toussaint, D. Geerinck, I. Hoste, F. Van Rossum, B. Cornier, R. Schumacker, A. Vanderpoorten et H. Vannerom. Jardin botanique national de Belgique, Meise. CXXXIX + 1195 pp. ISBN : 9789072619884.
  • MNHNL, 2000-. Duchesnea indica (Andrews) Th.Wolf in Recorder-Lux, database on the natural heritage of the Grand Duchy of Luxembourg. Musée national d’histoire naturelle, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-09-05]
  • MNHNL, iNaturalist & GBIF, 2019. Duchesnea indica (Andrews) Th.Wolf in MNHNL-mdata, online portal combining species observation from Recorder-Lux, iNaturalist and GBIF. National Museum of Natural History, Luxembourg. URL: https://mdata.mnhn.lu [Accessed 2019-09-06]
  • Ries, C. & Y. Krippel, 2021. First records of 56 invasive alien vascular plants in Luxembourg. Bulletin de la Société des naturalistes luxembourgeois 123: 115-127. [PDF 241 KB]
  • Ries, C., Y. Krippel & M. Pfeiffenschneider, 2020. Risk assessment after the Harmonia+ protocol of invasive alien vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 122: 197-205. [PDF 132 KB]
  • Ries, C., Y. Krippel, M. Pfeiffenschneider & S. Schneider, 2013. Environmental impact assessment and black, watch and alert list classification after the ISEIA Protocol of non-native vascular plant species in Luxembourg. Bull. Soc. Nat. luxemb. 114: 15-21. [PDF 652 KB]

 Page content last updated on 2021-03-03. Last proofread by Caroline Grounds on 2019-11-14.