Chaetogammarus ischnus (Stebbing, 1899)

Posted on2026-08-18AuthorManou Pfeiffenschneider

		Status LU: present
		Status Eur.: established.
		RA: ISEIA: n/a. Harmonia+: n/a.
Granataugen-Flohkrebs		Wikipedia: / \| Wikispecies:/
		Back to the list of invertebrates

Brief description

Chaetogammarus ischnus (Stebbing, 1899) originates from the Caspian and Black Sea regions. It is a small, slender species with a body length of up to 12 mm. In living specimens, the eyes are bright red, the antennae are orange, and the body is translucent and reddish. The antennae are long and hairy. Its preferred habitats are the lower reaches of larger rivers and streams, canals, and lakes. The species competes with native amphipods for habitat and food. There are no known significant negative impacts on other species groups. Chaetogammarus ischnus occurs sporadically in Germany but is often found in high densities on rock embankments in waterways (e.g., the Rhine and Havel), where it is frequently the dominant species alongside Dikerogammarus villosus. It is a predatory omnivore (feeding on other small animals, insect larvae, and fish eggs) (Müller et al 2018, Kanton Aargau 2026).

Status and distribution in Luxembourg

Records of somethingelse in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 1970-01-01.

Among invasive amphipods, the Pontocaspian species Chaetogammarus ischnus showed an increase in its population between 2018 and 2023, with high prevalence in the Moselle (from Stadtbredimus to Wasserbillig) and the Saar (monitoring by the LfU Rhineland-Palatinate State Office for the Environment).

Risk assessment

ISEIA protocol

no assessed yet

Harmonia+ protocol

no assessed yet

Worldwide distribution

GBIF: https://www.gbif.org/taxon/TC9N#map

Bibliography

Kanton Aargau, 2026. Neobiota in Gewässern, https://www.ag.ch/de/themen/umwelt-natur/neobiota/neobiota-in-gewaessern?jumpto=Njc1NzcwMC9iZDMxMzc3YS0wMzdjLTQ0NTYtOWEyYS0xODA0MmM0OGNjZjM [Accessed 2026-08-18]
Müller, R., C. Wolter & T. Peschel, 2018. Neobiota in Berliner Gewässern im Jahr 2018, Wirbellose Tiere, Fische und Wasserpflanzen, Planungsbüro Hydrobiologie Berlin, Im Auftrag der Senatsverwaltung für Umwelt, Verkehr und Klimaschutz, Abteilung Integrativer Umweltschutz, Referat Wasserwirtschaf, pp. 143.

Page content last updated on 2026-08-18.

Branchiura sowerbyi Beddard, 1892

Posted on2026-08-182026-08-18AuthorManou Pfeiffenschneider

		Status LU: present
		Status Eur.: established.
		RA: ISEIA: n/a. Harmonia+: n/a.
		Wikipedia: / \| Wikispecies:/
		Back to the list of invertebrates

Brief description

Branchiura sowerbyi Beddard, 1892 is a cosmopolite freshwater oligochaete. It is widespread in Europe and North America and also known in Asia, South America, Australia and South Africa. Its earliest records come from South East Asia and botanical gardens in Europe. Distribution patterns led to the conclusion that the species originated from the Sino-Indian region and was spread elsewhere by human activity. Fauna Europaea reports the species from 22 countries throughout Europe where it usually occurs in shallow, very warm stagnant or slowly flowing waters (Grabowski, M. & A. Jabłońska, 2009).

Status and distribution in Luxembourg

Records of somethingelse in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 1970-01-01.

In 1959, Jules A. Hoffmann caught Branchiures in the Moselle River near Remich. Subsequent surveys revealed a massive population in the border section of the Moselle. Furthermore, the species was moving upstream along the lower Sûre: by 1965, it had passed Moersdorf (J. Hoffmann 1970). Mauch (1962, 1963) confirmed the presence of this non-native species in the Moselle River between Schengen and Wasserbillig (Dhur & Massard 1995). The species is said to have been present in France’s Moselle River since 1935. A few individuals were also observed in 2023 at a monitoring station on the Moselle in Palzem, across from Stadtbredimus, but not in the Sauer.

Risk assessment

ISEIA protocol

no assessed yet

Harmonia+ protocol

no assessed yet

Worldwide distribution

GBIF: https://www.gbif.org/taxon/N6WK

Bibliography

Dhur, G. & J.-A. Massard, 1995. Etude historique et faunistique des invertébrés immigrés ou introduits dans la Moselle luxembourgeoise et ses affluents, Bulletin de la société des naturalistes luxembourgeoies, 96 (1995), p. 127 – 156.
Grabowski, M. & A. Jabłońska, 2009. First records of Branchiura sowerbyi Beddard, 1892 (Oligochaeta: Tubificidae) in Greece, Aquatic Invasions (2009) Volume 4, Issue 2: 365-367.

Page content last updated on 2026-08-18.

Dikerogammarus haemobaphes (Eichwald, 1841)

Posted on2026-08-182026-08-18AuthorManou Pfeiffenschneider

Demon shrimp		Status LU: present
		Status Eur.: established.
		RA: ISEIA: n/a. Harmonia+: n/a.
Kleiner Höckerflohkrebs		Wikipedia: \| Wikispecies: /
Kleine rimpelvlokreeft		Back to the list of invertebrates

Brief description

Dikerogammarus haemobaphes (Eichwald, 1841) is a species of freshwater gammarid crustacean. These gammarids are commonly known as demon shrimp, likely because they are an extremely successful invasive species. Native to the Ponto Caspian basin, Dikerogammarus haemobaphes expanded their range in the 1950s. This expansion began in Lake Balaton, Hungary and then spread into certain rivers and lakes in Austria, Belgium, Germany, Poland, Russia, Ukraine, and the United Kingdom. These crustaceans likely broadened their range due to the interconnection of waterways in Europe and the use of transportation vectors such as boats and ships (Wikipedia contributors, 2023).

Status and distribution in Luxembourg

Records of somethingelse in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 1970-01-01.

The species was recorded in 2008/2009 in the French part of the Moselle (Labat et al. 2011), and was detected in the Moselle in Luxembourg in both 2018 and 2024 during monitoring by the LfU Rhineland-Palatinate State Office for the Environment.

Risk assessment

ISEIA protocol

no assessed yet

Harmonia+ protocol

no assessed yet

Worldwide distribution

GBIF: https://www.gbif.org/taxon/364SM#map

Bibliography

Labat, F., C. Piscart, B. Fontan, 2011. First records, pathways and distributions of four new Ponto-Caspian amphipods in France, Limnologica Volume 41, Issue 4, December 2011, Pages 290-295
Wikipedia contributors, 2023. Dikerogammarus haemobaphes, Wikipedia, The Free Encyclopedia, 28 March 2023, 15:10 UTC, <https://en.wikipedia.org/wiki/Dikerogammarus haemobaphes> [Accessed 2025-10-22]

Page content last updated on 2026-08-18.

Health department releases information about the Asian tiger mosquito and asks for the public’s cooperation

Posted on2026-07-232026-07-23AuthorManou Pfeiffenschneider

On its website, the health department provides information about the health risks posed by the tiger mosquito, offers advice on how to identify it and explains how to help prevent the species from spreading. It also introduces the ‘Mosquito Alert’ app, which can be used to report sightings of the species.

Page content last updated on 2026-07-23.

Nezara viridula

Posted on2026-01-052026-01-08AuthorManou Pfeiffenschneider

	Southern green shield bug	Status LU: established
		Status Eur.: established.
	Punaise verte puante	RA: ISEIA: n/a. Harmonia+: n/a.
	Grüne Reiswanze	Wikipedia: \| Wikispecies:
	Zuidelijke groene schildwants	Back to the list of invertebrates

Brief description

Nezara viridula L., commonly known as southern green shield bug or green vegetable bug, is a plant-feeding stink bug. Believed to have originated in Ethiopia, it can now be found across the world due to its strong flight and human transport along trade routes. Because of its preference for certain species of legumes, such as beans and soybeans, it is an economically important pest on such crops.

Status and distribution in Luxembourg

Records of Nezara viridula L. in Luxembourg. Data source: Recorder-Lux, iNaturalist & GBIF, 1970-01-01.

The first documented sighting of this species in Luxembourg was in Hesperange in 2019. Based on the data found in the Recorder-Lux database, the species has established itself primarily in the centre of the country and in the Moselle valley. It appears to be less common in the Ösling region so far.

Risk assessment

ISEIA protocol

no assessed yet

Harmonia+ protocol

no assessed yet

Worldwide distribution

GBIF (2026): https://www.gbif.org/species/2078852

Bibliography

Wikipedia contributors, 2025. Nezara viridula, Wikipedia, The Free Encyclopedia, 7 October 2025, 17:22 UTC, <https://en.wikipedia.org/wiki/Nezara_viridula> [Accessed 2026-01-05]

Page content last updated on 2026-01-08.

Parliamentary question of 28th August 2025 regarding invasive alien species

Posted on2025-10-11AuthorManou Pfeiffenschneider

On 28th August 2025, Jeff Engelen and Alexandra Schoos, Members of the Chamber of Deputies, addressed a parliamentary question to the Minister of the Environment regarding invasive alien species.

Page content last updated on 2025-10-11. Last proofread by Caroline Grounds on 2019-12-19.

Parliamentary question of 30th July 2025 regarding the occurence of Cyperus esculentus in Luxembourg

Posted on2025-10-012025-10-11AuthorManou Pfeiffenschneider

On 30th July 2025, Jeff Boonen and Octavie Modert, Members of the Chamber of Deputies, addressed a parliamentary question to the Minister of Agriculture and the Minister of the Environment regarding the occurence of Cyperus esculentus in Luxembourg.

Page content last updated on 2025-10-11. Last proofread by Caroline Grounds on 2019-12-19.

Update of the list of IAS of Union concern

Posted on2025-07-272025-07-27AuthorManou Pfeiffenschneider

The European Commission published an update of the list of invasive alien species of Union concern in the Official Journal on July 18th 2025: Commission Implementing Regulation (EU) 2025/1422 of 17 July 2025 amending Implementing Regulation (EU) 2016/1141 to update the list of invasive alien species of Union concern.

26 species have been added to the list. Reynoutria japonica, R. sachalinensis, R. x bohemica and Crassula helmsii can be considered the most relevant for Luxembourg on the updated list.

Page content last updated on 2025-07-27.

First documented occurence of Ludwigia grandiflora in Luxembourg

Posted on2025-07-222025-07-30AuthorManou Pfeiffenschneider

Picture by Stefan Ehl, EFOR-ERSA

The water primrose (Ludwigia grandiflora (Michx.) Greuter & Burdet), IAS of union concern since 2016, was first documented for Luxembourg on 21 July 2025 by Stefan Ehl in a dried out pond near Leudelange.

Picture by Stefan Ehl, EFOR-ERSA

Page content last updated on 2025-07-30.

New brochure on invasive neophytes and their alternatives

Posted on2025-05-022025-05-02AuthorManou Pfeiffenschneider

A new brochure provides information on invasive neophytes and their alternatives, which are particularly suitable for landscaping gardens and green spaces as well as for promoting biodiversity. The guide is aimed at the entire horticultural and urban planning sector as well as local authorities and private individuals. The brochure in German elaborated by Emweltberodung Lëtzebuerg and published by Administration de la nature et des forêts can be downloaded here: neophyte-guide.

Page content last updated on 2025-05-02.