American skunk-cabbage, swamp lantern	Status LU: casual. 1st record: 2022
	Amerikanesch Heckepëppchen	Status Eur.: established. 1st record: UK 1901.1 IAS of EU concern (2016).
	Lysichiton américain	RA: ISEIA: B1, Watch List. Harmonia+: 0,14
	Amerikanischer Stinktierkohl	Wikipedia: | Wikispecies: | CABI
	Moeraslantaarn	Back to the list of neophytes

Brief description

Lysichiton americanus Hultén & H. St. John grows in the transition zone of terrestrial, semi-aquatic and aquatic habitats like swamps, fens, wet meadows, marshy and alluvial woodlands, along streams, riverbanks, lakesides and ponds. It has no specific site condition requirements except the presence of saturated organic soils. It is often found in protected semi-natural habitats. Lysichiton reproduces almost exclusively by seeds, which may be dispersed downstream along waterways. However, spread by natural means is not frequent and rather limited. L. americanus has become established locally in swamp forests and associated wetlands in the EPPO region (resulting most of the time from plantation in the site). After some years, its huge leaves build a dense layer excluding light from native species which are usually not adapted to extreme darkness. It can displace and cause local extinction of rare species of mosses and vascular plants (Carex echinata, Viola palustris, and orchids). (Branquart et al. 2010).

IAS of Union concern

In 2016, Lysichiton americanus Hultén & H. St. John 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

Lysichiton americanus Hultén & H. St. John was first documented by Christiane Wolff via iNaturalist on 2022-05-31 and was confirmed by Maximilien Oly on 2022-06-02 in the Mamer valley close to Kopstal. Three individuals have been differenciated next to a tributary of the Mamer. The small population was eradicated by the local forestry service. The origin of the population has not been identified.

Risk assessment

ISEIA protocol

B1 (2+3+3+2) = Watch List. First assessed 2019-01-24 by Manou Pfeiffenschneider and Christian Ries.

Harmonia+ protocol

Overall risk score 0,14 = (Overall Invasion score 0,34 x Overall Impact score 0,40) (Ries et al. 2020).

Worldwide distribution

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, S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove, 2010. Harmonia database: Lysichiton americanus Hultén & H. St. John. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-11-21]
• CABI, 2021. Lysichiton americanus. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2021-03-04]
• MNHNL, iNaturalist & GBIF, 2020. Lysichiton americanus 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 2020-03-02]
• 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 & 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]

 Page content last updated on 2023-08-17. Last proofread by Caroline Grounds on 2019-11-19.

1. Cf. CABI 2021.[↩]

	Creeping water primrose	Status LU: absent. 1st record: n/a.
	Krauchend Waasserprimmel	Status Eur.: established. 1st record: FR 1830s. 1 IAS of EU concern (2016).
	Jussie rampante	RA: ISEIA: A0, Alert List. Harmonia+: 0,44
	Kriechendes Heusenkraut	Wikipedia: | Wikispecies: | CABI
	Kleine waterteunisbloem	Back to the list of neophytes

Brief descritpion

Ludwigia peploides (Kunth.) P.H. Raven is an amphibious plant living in ponds, lakes, ditches, channels and slow-running rivers as well as in humid meadows. It shows a high tolerance to different water levels. Its growth is favoured by water eutrophication but the plant is able to develop in oligotrophic environments. Both clonal and sexual reproductions contribute to plant spread across watersheds. Water primroses are highly detrimental to the environment in western Europe. They quickly develop and make very thick monospecific floating carpets at the surface of water bodies. They alter the physico-chemical quality of water (reduction of light and dissolved oxygen) and possess an allelopathic activity that influences the water quality throughout the year and reduces the germination and survival rates of other plant species. They outcompete most native water plants and create an anoxic environment detrimental to many plant and animal species. In addition, they modify water flow and cause wetland drying (Branquart et al. 2013).

IAS of Union concern

In 2016, Ludwigia peploides (Kunth.) P.H. Raven 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

Ludwigia peploides (Kunth.) P.H. Raven has not yet been observed in Luxembourg (MNHNL, iNaturalist & GBIF 2020).

Risk assessment

ISEIA protocol

A0 (3+3+2+3) = Alert List. First assessed 24 January 2019 by Manou Pfeiffenschneider and Christian Ries.

Harmonia+ protocol

Overall risk score 0,44 = (Overall Invasion score 0,59 x Overall Impact score 0,75) (Ries et al. 2020).

Worldwide distribution

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., S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove, 2013. Harmonia database: Ludwigia peploides (Kunth.) P.H. Raven. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-11-21]
• CABI, 2021. Ludwigia peploides. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2021-03-04]
• MNHNL, iNaturalist & GBIF, 2020. Ludwigia peploides 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 2020-03-02]
• 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]

 Page content last updated on 2021-03-04. Last proofread by Caroline Grounds on 2019-11-19.

	Water primrose	Status LU: absent. 1st record: n/a.
	Groussbléieg Waasserprimmel	Status Eur.: established. 1st record: FR 1830s.1 IAS of EU concern (2016).
	Jussie à grandes fleurs, Grande J.	RA: ISEIA: A0, Alert List. Harmonia+: 0,28
	Großblütiges Heusenkraut	Wikipedia: | Wikispecies: | CABI
	Waterteunisbloem	Back to the list of neophytes

Brief description

Ludwigia grandiflora (Michx.) Greuter & Burdet is an amphibious species living in ponds, lakes, ditches, channels and slow-running rivers as well as in humid meadows. It shows a high tolerance to different water levels. Its growth is favoured by water eutrophication but the plant is able to develop in oligotrophic environments. Invasive spread across watersheds is almost exclusively clonal and brought about by the dispersal of vegetative propagules by waterflow. Water primroses are highly detrimental to the environment in western Europe. They quickly develop and make very thick monospecific floating carpets at the surface of water bodies. They alter the physico-chemical quality of water (reduction of light and dissolved oxygen) and possess an allelopathic activity that influences the water quality throughout the year and reduces the germination and survival rates of other plant species. They outcompete most native water plants and create an anoxic environment detrimental to many plant and animal species. In addition, they modify water flow and cause wetland drying (Branquart et al. 2013).

IAS of Union concern

In 2016, Ludwigia grandiflora (Michx.) Greuter & Burdet 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

Ludwigia grandiflora (Michx.) Greuter & Burdet has not yet been observed in Luxembourg (MNHNL, iNaturalist & GBIF 2020).

Risk assessment

ISEIA protocol

A0 (3+3+2+3) = Alert List. First assessed 24 January 2019 by Manou Pfeiffenschneider and Christian Ries.

Harmonia+ protocol

Overall risk score 0,28 = (Overall Invasion score 0,46 x Overall Impact score 0,62) (Ries et al. 2020).

Worldwide distribution

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, S. Vanderhoeven, W. Van Landuyt, F. Van Rossum & F. Verloove, 2013. Harmonia database: Ludwigia grandiflora (Michx.) Greuter & Burdet. Harmonia version 1.2, Belgian Forum on Invasive Species. URL: http://ias.biodiversity.be [accessed on 2019-11-21]
• CABI, 2021. Ludwigia grandiflora. In: Invasive Species Compendium. Wallingford, UK: CAB International. URL: www.cabi.org/isc [accessed 2021-03-04]
• MNHNL, iNaturalist & GBIF, 2020. Ludwigia grandiflorain 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 2020-03-02]
• 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]

 Page content last updated on 2021-03-04. Last proofread by Caroline Grounds on 2019-11-19.

1. Cf. CABI 2021.[↩]