- Summary of Invasiveness
- Taxonomic Tree
- Notes on Taxonomy and Nomenclature
- Diseases Table
- Distribution Table
- History of Introduction and Spread
- Risk of Introduction
- Pathogen Characteristics
- Hosts/Species Affected
- Host Animals
- Biology and Ecology
- Notes on Natural Enemies
- Pathway Causes
- Pathway Vectors
- Impact Summary
- Economic Impact
- Environmental Impact
- Threatened Species
- Risk and Impact Factors
- Distribution Maps
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PicturesTop of page
IdentityTop of page
Preferred Scientific Name
- Anguillicoloides crassus (Kuwahara, Niimi et Itagaki, 1974)
Other Scientific Names
- Anguillicola crassus Kuwahara, Niimi et Itagaki, 1974
International Common Names
- English: anguillicolosis; swim bladder worm; swimming bladder worm
Local Common Names
- Denmark: svømmeblæreorm
- Germany: Schwimmblasenwurm
- Netherlands: zwemblaasworm
- Poland: angwilikola
- Sweden: simblåsemask
Summary of InvasivenessTop of page
A. crassus is native to eastern Asia where it is a widespread, non-pathogenic parasite of the swimbladder of Anguilla japonica. Introduced to Germany with imported Japanese eels around 1980, it transferred to the European eel Anguilla anguilla and has subsequently spread throughout Europe and northern Africa. Following introduction to America, in less than 20 years it has spread from Texas to Cape Breton in Anguilla rostrata. It has the attributes of an excellent coloniser, including high fecundity, low intermediate host specificity and the ability to use a wide range of freshwater fish as paratenic hosts. These, and the uncontrolled transfers of live eels by man, have facilitated its spread and made it the most invasive helminth known. It can be highly pathogenic to Atlantic eels, damaging swimbladders and able to cause mortalities. It affects eels’ swimming abilities and it is feared that it reduces their ability to migrate to their marine spawning grounds.
Taxonomic TreeTop of page
- Domain: Eukaryota
- Kingdom: Metazoa
- Phylum: Nematoda
- Class: Secernentea
- Subclass: Spiruria
- Order: Camallanida
- Suborder: Camallanina
- Family: Anguillicolidae
- Genus: Anguillicoloides
- Species: Anguillicoloides crassus
Notes on Taxonomy and NomenclatureTop of page
Adults of all five species are parasitic in the swim bladders of eels of the genus Anguilla. The preferred host of each is a species of Pacific eel and their heartland and the original area of their distribution is in Asia and Africa, i.e. in countries bordered by the Pacific and Indian oceans. Thus, Anguillicola globiceps Yamaguti, 1935 is a parasite of Anguillajaponica and its native distribution is in China and Japan. A. crassus is probably widespread throughout China, Japan and Korea and its preferred host there is also Anguilla japonica, but Moravec (2006) believes that it may have been introduced into Japan with imports of eels and that its region of origin is elsewhere in the Pacific. The antipodean species Anguillicoloides australiensis (Johnston and Mawson, 1940) Moravec and Taraschewski, 1988 is restricted to Australia and (probably) New Zealand, and infects the long-finned eels Anguilla reinhardtii and, probably, Anguilla dieffenbachii. The other antipodean species, Anguillicoloides novaezelandiae Moravec and Taraschewski, 1988, is a native of New Zealand but also occurs in Australia, and it infects the short-finned eel Anguilla australis. The remaining species, Anguillicoloides papernai Moravec and Taraschewski, 1988, is a native of South Africa and infects the African long-finned eel Anguilla mossambica. It would seem possible that there may be other species in the genus still to be described which infect other species of Pacific eels, but the parasite fauna of these species is still very poorly known. There are no species of anguillicolid native to the Atlantic eels Anguilla anguilla and Anguilla rostrata.
DistributionTop of page
It would appear that A. crassus was originally restricted to East Asia throughout which it is probably widespread and endemic, especially in China, Japan, Korea and Taiwan (there are not many records of its being definitely identified in China, probably because as a non-pathogenic species it is likely to be considered unimportant, and because of its similarity to Anguillicola globiceps). It is likely that it is present in other countries in this region and it has been reported from Thailand (Moravec, 2006) but there have been very few or no published reports of eel parasites from many parts of Eastern Asia. Its natural range probably coincides with that of its preferred host Anguilla japonica.
Distribution TableTop of page
The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.Last updated: 10 Jan 2020
|Continent/Country/Region||Distribution||Last Reported||Origin||First Reported||Invasive||Reference||Notes|
|Morocco||Present, Localized||Introduced||Invasive||Known since 1999|
|Réunion||Present, Localized||Introduced||Invasive||Reported from African eel species, and believed to have been introduced by man|
|Tunisia||Present, Localized||Introduced||Invasive||In one lake system, but extending range|
|China||Present||Present based on regional distribution.|
|Japan||Present||Present based on regional distribution.|
|-Hokkaido||Present, Widespread||Native||Especially in culture|
|-Honshu||Present, Widespread||Native||Culture in wild|
|South Korea||Present||Native||Reported from culture|
|Taiwan||Present, Widespread||Native||Wild and in culture|
|Turkey||Present||Introduced||Invasive||In several rivers|
|Austria||Present, Localized||Introduced||Invasive||Foci in stocked lakes|
|Belgium||Present, Widespread||Introduced||Invasive||First records 1980s|
|Czechia||Present, Widespread||Introduced||Invasive||Introduced with eel stocking|
|Denmark||Present, Widespread||Introduced||Invasive||Introduced with eel stocking|
|France||Present, Widespread||Introduced||Invasive||Early introduction into south|
|Germany||Present, Widespread||Introduced||Invasive||First record from Europe in Weser-Ems in 1982. Now in all major rivers.|
|Hungary||Present, Localized||Introduced||Invasive||Usually in stocked lakes, especially Lake Balaton|
|Ireland||Present, Widespread||Introduced||Invasive||First report 1998, but now spreading rapidly. Introduced with eel trade|
|Italy||Present, Widespread||Introduced||Invasive||Introduced with eels imported from France. Mainly in eel culture|
|Netherlands||Present, Widespread||Introduced||Invasive||First reported soon after arrival in Europe|
|Norway||Present, Localized||Introduced||Invasive||Slower colonisation near limit of the species range|
|Portugal||Present, Widespread||Introduced||Invasive||Often in coastal lagoons|
|Russia||Present||Present based on regional distribution.|
|-Central Russia||Present, Localized||Introduced||Invasive||Mainly around Kaliningrad and Baltic Sea|
|Slovakia||Present, Localized||Introduced||Invasive||In River Danube system|
|Spain||Present, Localized||Introduced||Invasive||Localisation may reflect areas of study|
|Sweden||Present, Localized||Introduced||Invasive||Initially only in thermal effluents but now spreading more widely in south.|
|United Kingdom||Present, Widespread||Introduced||Invasive||Introduced with eel trade in south and east in 1987. Now widespread all over including Scotland.|
|Canada||Present||Present based on regional distribution.|
|-New Brunswick||Present, Widespread||Introduced||Invasive|
|-Newfoundland and Labrador||Present, Widespread||Introduced||Invasive|
|-Nova Scotia||Present, Widespread||Introduced||Invasive|
|-Prince Edward Island||Present, Widespread||Introduced||Invasive|
|United States||Present||Present based on regional distribution.|
|-New York||Present, Localized||Introduced||Invasive||In Hudson River watershed|
|-South Carolina||Present, Localized||Introduced||Invasive|
|-Texas||Present||Introduced||Invasive||First record in N. America; First reported: circa 1995|
History of Introduction and SpreadTop of page
A. crassus is the most efficient invasive helminth known (Nagasawa et al., 1994) but its rapid spread throughout the distribution range of the two species of Atlantic eel has been facilitated by, and is due in no small measure to, the uncontrolled inter-continental transfer of live eels. Its spread has, in fact, been so rapid that it has exceeded the rate at which it can be documented and any published account is invariably out of date. References cited in the table therefore tend to report the early stages of invasion as it is not possible to keep pace with the parasite’s subsequent spread throughout a country. It is already widespread throughout Europe (Ashworth and Blanc, 1997; Kirk, 2003; Moravec, 1992, 2006) and it can be predicted that its distribution range in Atlantic eels will become congruent with that of the eels themselves.
IntroductionsTop of page
|Introduced to||Introduced from||Year||Reason||Introduced by||Established in wild through||References||Notes|
|Natural reproduction||Continuous restocking|
|Germany||circa 1982||Aquaculture (pathway cause)||Yes||Koops and Hartmann (1989); Neumann (1985)||First introduction in Europe, to Bremerhaven probably from Taiwan, imported with live eels|
|Italy||France||Aquaculture (pathway cause)||Introduced with eel imports|
|Texas||Asia||Aquaculture (pathway cause)||Yes||Wielgoss et al. (2008)||From Asia, probably Japan, to Texas, N. America|
|UK||1987||Aquaculture (pathway cause)||Introduced with eel imports|
Risk of IntroductionTop of page
Although movements of eels for purposes of stocking and farming have played a major role in the rapid and widespread dissemination of A. crassus (Kennedy and Fitch, 1990; Belpaire et al., 1989) it is important to appreciate that A. crassus itself possesses many of the attributes of a successful coloniser (Kennedy and Fitch, 1990). These include: 1) a high reproductive potential, 2) a relatively simple life cycle with a low degree of specificity towards its intermediate host, including estuarine species of copepod, 3) the ability to use a wide range of fish species as paratenic hosts, 4) free living L2 larvae capable of surviving and remaining infective for long periods in freshwater of a range of salinities and in sea water, 5) the capability of infecting eels of all sizes, 6) the ability to survive for long periods in eels living in sea water, and 7) escaping the restrictions of a narrow specificity to its definitive host by using a species of fish that is itself widespread in distribution and capable of surviving a wide range of habitat and environmental conditions. It also occupies the swimbladder of an eel, a habitat in which there is no competitor. Every eel within the temperature and pH range of A. crassus is thus potentially at risk of infection. A combination of the colonisation abilities of the parasite, the natural movements of eels themselves and transfers of eels by man have enabled A. crassus to colonise Europe, North America and North Africa within 25 years: this is an extraordinary achievement.
Pathogen CharacteristicsTop of page
A. crassus is, like all anguillicolids, parasitic as an adult in the lumen of the swimbladder of its eel host. Eels acquire infections by ingestion of an infected copepod, the intermediate host, or by ingestion of an infected fish, a paratenic host. In either case, the L3 larvae migrate to the swimbladder wall of the eel, where they moult to the L4 stage and eventually move into the lumen of the swimbladder and develop into adults. The adult is a large nematode with a stout body tapering at each end. It is a blood feeder with a well-developed buccal capsule, a row of circumoral teeth and a muscular oesophagus. The presence of blood and the breakdown products of blood in the intestine give the whole nematode a dark, almost black, appearance. The sexes are separate. The body wall and other organs are typical of nematodes in general. Males range in length from about 6-23 mm and in width from 0.3 to 1.8 mm, whilst females range from 13-45 mm in length and from 1.2 – 5.0 mm in width. Females in particular appear very robust. They are ovoviviparous: the uterus occupies most of the space of the body and contains eggs which in turn contain developing embryos and fully formed larvae (L2). A single female may contain up to 500,000 eggs (Kennedy and Fitch, 1990). The eggs may hatch inside the female to release the larvae, or may be shed from the female and hatch in the pneumatic duct so that the larvae pass out to the exterior with the eel faeces. Females die in the swim bladder, which then contains live worms of each sex as well as disintegrating parasite tissues and numerous eggs. The presence of adult parasites, both living and dead, brings about characteristic changes in the thickness of the swimbladder wall and affects the gas content and functioning of the swimbladder.
Hosts/Species AffectedTop of page
As far as is known, all individuals of Anguilla anguilla are equally at risk of infection by A. crassus: small individuals by eating infected copepods and large individuals by eating infected fish. There is no resistance to re-infection (Haenen et al., 1996) and antibodies produced against the parasite have no protective function (Knopf and Lucius, 2008). Once A. crassus has entered a lake or eel farm, its prevalence often rises to 100%, and transmission rates and infection levels may be very high when eel densities are themselves high as in eel farms or shallow lakes (Molnár et al., 1994; Baruš et al. 1999a). Stress in individual eel hosts may predispose them to disease (Gollock et al., 2005a).
Host AnimalsTop of page
|Animal name||Context||Life stage||System|
|Anguilla anguilla (European eel)||Domesticated host; Wild host||Aquatic|All Stages||Enclosed systems/Freshwater recirculating systems; Enclosed systems/Ponds; Enclosed systems/Raceways / running water ponds; Enclosed systems/Tanks|
|Anguilla japonica (Japanese eel)||Domesticated host; Wild host||Aquatic|Adult; Aquatic|Fry||Enclosed systems/Ponds|
|Anguilla rostrata (american eel)||Domesticated host; Wild host|
|Ariosoma balearicum||Experimental settings|
Biology and EcologyTop of page
The genetics of this species have been intensively studied, for more details see Heitlinger et al. (2009).
ClimateTop of page
|C - Temperate/Mesothermal climate||Preferred||Average temp. of coldest month > 0°C and < 18°C, mean warmest month > 10°C|
|Cf - Warm temperate climate, wet all year||Preferred||Warm average temp. > 10°C, Cold average temp. > 0°C, wet all year|
|Cs - Warm temperate climate with dry summer||Tolerated||Warm average temp. > 10°C, Cold average temp. > 0°C, dry summers|
|Cw - Warm temperate climate with dry winter||Tolerated||Warm temperate climate with dry winter (Warm average temp. > 10°C, Cold average temp. > 0°C, dry winters)|
|D - Continental/Microthermal climate||Tolerated||Continental/Microthermal climate (Average temp. of coldest month < 0°C, mean warmest month > 10°C)|
Notes on Natural EnemiesTop of page
There are no known natural enemies of A. crassus as such. There will always be some mortality of L2s through being eaten by copepods that are not suitable intermediate hosts and of L3s in paratenic hosts being eaten by fish other than eels or by birds, but there is no known predator or hyperparasite of adult parasites.
Pathway CausesTop of page
Pathway VectorsTop of page
Impact SummaryTop of page
|Fisheries / aquaculture||Negative|
Economic ImpactTop of page
In the cases of the eel mortalities attributed to A. crassus in European lakes, the only figures available relate to mortalities. Thus, Molnár et al. (1991, 1994) state that in 1991, 200 tonnes of eels died in Lake Balaton, and in 1992 40 tonnes. Baruš et al. (1999a) similarly quote a figure 3.5 tonnes of eels killed in the Vranov Dam in 1994, but no financial values have been attached to these losses. It must be presumed that there was a severe economic loss to professional eel fishermen as a consequence of the mortalities but no figures are available to support this presumption.
Environmental ImpactTop of page
Impact on biodiversity
The effects of A. crassus on wild eel populations are more difficult to study than those on captive ones, but experiments suggest that infected eels are more likely to die in adverse conditions (Didziulis, 2006). Mass mortalities have been reported among wild eels, but only when there have been particular combinations of unfavourable circumstances (for more details, see datasheet on Anguillicolosis). Concern has been expressed that severe damage to the swimbladder may reduce the ability of eels to migrate to their spawning grounds in the Sargasso Sea, which could have a severe impact on the future of the population (Didziulis, 2006). Such a decline could have significant effects on ecosystem community structure.
Threatened SpeciesTop of page
Risk and Impact FactorsTop of page
- Proved invasive outside its native range
- Has a broad native range
- Abundant in its native range
- Highly adaptable to different environments
- Fast growing
- Has high reproductive potential
- Has propagules that can remain viable for more than one year
- Host damage
- Negatively impacts aquaculture/fisheries
- Parasitism (incl. parasitoid)
- Highly likely to be transported internationally accidentally
- Highly likely to be transported internationally illegally
- Difficult to identify/detect as a commodity contaminant
- Difficult to identify/detect in the field
- Difficult/costly to control
ReferencesTop of page
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Køie M, 1991. Swimbladder nematodes (Anguillicola spp.) and gill monogeneans (Pseudodactylogyrus spp.) parasitic on the European eel (Anguilla anguilla). Journal de la Conseil International pour Exploration de la Mer, 47:391-398.
Maamouri F; Gargouri L; Ould Daddah M; Bouix G, 1999. Occurrence of Anguillicola crassus (Nematode, Anguillicolidae) in the Ichkeul Lake (Northern Tunisia). Bulletin of the European Association of Fish Pathologists, 19(1):17-19.
Machut LS; Limburg KE, 2007. Anguillicola crassus infection in Anguilla rostrata from small tributaries of the Hudson River watershed, New York, USA. Diseases of Aquatic Organisms, 79(1):37-45. http://www.int-res.com/abstracts/dao/v79/n1/p37-45/
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Molnár K, 1994. Formation of parasitic nodules in the swimbladder and intestinal walls of the eel Anguilla anguilla due to infections with larval stages of Anguillicola crassus. Diseases of Aquatic Organisms, 20(3):163-170.
Molnár K; Baska F; Csaba G; Glávits R; Székely C, 1993. Pathological and histopathological studies of the swimbladder of eels Anguilla anguilla infected by Anguillicola crassus (Nematoda: Dracunculoidea). Diseases of Aquatic Organisms, 15(1):41-50.
Moravec F, 1996. Aquatic invertebrates (snails) as new paratenic hosts of Anguillicola crassus (Nematoda: Dracunculoidea) and the role of paratenic hosts in the life cycle of this parasite. Diseases of Aquatic Organisms, 27(3):237-239.
Moravec F; Cave D di; Orecchia P; Paggi L, 1993. Studies on the development of Anguillicola crassus Kuwahara, Niimi et Itagaki, 1974 (Nematoda: Dracunculoidea) in the intermediate host. Folia Parasitologica, 40(1):39-48.
Moravec F; Cave D di; Orecchia P; Paggi L, 1994. Present occurrence of Anguillicola novaezelandiae (Nematoda: Drancunculoidea) in Europe and its development in the intermediate host. Folia Parasitologica, 41:203-208.
Moravec F; Di Cave D; Orecchia P; Paggi L, 1994. Experimental observations on the development of Anguillicola crassus (Nematoda: Dracunculoidea) in its definitive host, Anguilla anguilla (Pisces). Folia Parasitologica, 41(2):138-148.
Moravec F; Konecny R, 1994. Some new data on the intermediate and paratenic hosts of the nematode Anguillicola crassus Kuwahara, Niimi et Itagaki, 1974 (Dracunculoidea), a swimbladder parasite of eels. Folia Parasitologica, 41(1):65-70.
Moravec F; Skoríková B, 1998. Amphibians and larvae of aquatic insects as new paratenic hosts of Anguillicola crassus (Nematoda: Dracunculoidea), a swimbladder parasite of eels. Diseases of Aquatic Organisms, 34(3):217-222.
Moravec F; Taraschewski H, 1988. Revision of the genus Anguillicola Yamaguti, 1935 (Nematoda: Anguillicolidae) of the swimbladder of eels, including descriptions of two new species A. novaezelandiae sp. n. and A. papernai sp. n. Folia Parasitologica, 35(2):125-146.
Münderle M; Sures B; Taraschewski H, 2004. Influence of Anguillicola crassus (Nematoda) and Ichthyophthirius multifiliis (Ciliophora) on swimming activity of European eel Anguilla anguilla. Diseases of Aquatic Organisms, 60(2):133-139. http://www.int-res.com/abstracts/dao/v60/n2/p133-139.html
Münderle M; Taraschewski H; Klar B; Chang CW; Shiao JC; Shen KN; He JT; Lin SH; Tzeng WN, 2006. Occurrence of Anguillicola crassus (Nematoda: Dracunculoidea) in Japnese eels Anguilla japonica from a river and an aquaculture unit in SW Taiwan. Diseases of Aquatic Organisms, 71:101-108.
Möller H; Holst S; Lüchtenberg H; Petersen F, 1991. Infection of eel Anguilla anguilla from the River Elbe estuary with two nematodes, Anguillicola crassus and Pseudoterranova decipiens. Diseases of Aquatic Organisms, 11(3):193-199.
Nagasawa K; Kim YG; Hirose H, 1994. Anguillicola crassus and A. globiceps (Nematoda: Dracunculoidea) parasitic in the swimbladder of eels (Anguilla japonica and A. anguilla) in East Asia: a review. Folia Parasitologica, 41(2):127-137.
Nielsen ME, 1999. An enhanced humoral immune response against the swimbladder nematode, Anguillicola crassus, in the Japanese eel, Anguilla japonica, compared with the European eel, A. anguilla. Journal of Helminthology, 73(3):227-232.
Ooi HongKean; Wang WayShyan; Chang HongYou; Wu ChwenHerng; Lin ChengChung; Hsieh MengTong, 1996. An epizootic of anguillicolosis in cultured American eels in Taiwan. Journal of Aquatic Animal Health, 8(2):163-166.
Paggi L; Orecchia P; Minervini R; Mattiucci S, 1982. [English title not available]. (Sulla comparsa de Anguillicola australiensis Johnston and Mawson, 1940 (Dracunculoidea: Anguillicolidae) in Anguilla anguilla del Lago di Bracciano.) Parassitologia, 24:139-144.
Paliková M; Navrátil S, 2001. Occurrence of Anguillicola crassus in the water reservoir Koryeany (Czech Republic) and its influence on the health condition and haematological index of eels. Acta Vetinaria Brno, 70:443-449.
Palstra AP; Heppener DFM; Ginneken VJT van; Szekely C; Thillart GEEJM van den, 2007. Swimming performance of silver eels is severely impaired by the swimbladder parasite Anguillicola crassus. Journal of Experimental Marine Biology and Ecology, 352(1):244-256.
Polzer M; Taraschewski H, 1993. Identification and characterisation of the proteolytic enzymes in the developmental stages of the eel-pathogenic nematode Anguillicola crassus. Parasitology Research, 79:24-27.
Rockwell LS; Jones KMM; Cone DK, 2009. First record of Anguillicoloides crassus (Nematoda) in American eels (Anguilla rostrata) in Canadian estuaries, Cape Breton, Nova Scotia. Journal of Parasitology, 95(2):483-486. http://www.journalofparasitology.org/perlserv/?request=get-abstract&doi=10.1645%2FGE-1739.1
Rolbiecki L, 2008. New data on the introduced exotic nematode Anguillicola crassus Kuwahara, Niimi and Ikagaki, 1974 in the eel Anguilla anguilla in Lake Wdzydze (Polish waters). Oceanological and Hydrobiological Studies, 37(3):37-48.
Sasal P; Taraschewski H; Valade P; Grondin H; Wielgoss S; Moravec F, 2008. Parasite communities in eels of the Island of Reunion (Indian Ocean): a lesson in parasite introduction. Parasitology Research, 102(6):1343-1350. http://www.springerlink.com/content/k4x12l501gl8504u/?p=57ab614532fd424085eac0de5dfd51c4&pi=31
Schabuss M; Kennedy CR; Konecny R; Grillitsch B; Reckendorfer W; Schiemer F; Herzig A, 2005. Dynamics and predicted decline of Anguillicola crassus infection in European eels, Anguilla anguilla, in Neusiedler See, Austria. Journal of Helminthology, 79(2):159-167. http://www.ingenta.com/journals/browse/cabi/joh
Schabuss M; Konecny R; Belpaire C; Schiemer F, 1997. Endoparasitic helminths of the European eel, Anguilla anguilla, from four disconnected meanders from the rivers Leie and Scheldt in western Flanders, Belgium. Folia Parasitologica, 44(1):12-18.
Scholz F; Zerbst-Boroffka I, 1994. Osmotic and ionic regulation of the eel parasite Anguillicola crassus (Nematoda) and its host (Anguilla anguilla). (Osmo-und ionenregulation des aalparasiten Anguillicola crassus (Nematoda) und seines wirtes (Anguilla anguilla).) Zoologische Beitreagen, 35:103-117.
Sjöberg NB; Petersson E; Wickström H; Hansson S, 2009. Effects of the swimbladder parasite Anguillicola crassus on the migration of European silver eels Anguilla anguilla in the Baltic Sea. Journal of Fish Biology, 74(9):2158-2170. http://www.blackwell-synergy.com/loi/jfb
Sprengel G; Lüchtenberg H, 1991. Infection by endoparasites reduces maximum swimming speed of European smelt Osmerus eperlanus and European eel Anguilla anguilla. Diseases of Aquatic Organisms, 11(1):31-35.
Sures B; Knopf K, 2004. Individual and combined effects of cadmium and 3,3’,4,4’,5-pentachlorobiphenyl (PCB 126) on the humoral immune response in European eel (Anguilla anguilla) experimentally infected with larvae of Anguillicola crassus (Nematoda). Parasitology, 128(4):445-454.
Sures B; Knopf K; Kloas W, 2001. Induction of stress by the swimbladder nematode Anguillicola crassus in European eels, Anguilla anguilla, after repeated experimental infection. Parasitology, 123(2):179-184.
Sures B; Knopf K; Taraschewski H, 1999. Development of Anguillicola crassus (Dracunculoidea, Anguillicolidae) in experimentally infected Balearic congers Ariosoma balearicum (Anguilloidea, Congridae). Diseases of Aquatic Organisms, 39(1):75-78.
Sures B; Knopf K; Würtz J; Hirt J, 1999. Richness and diversity of parasite communities in European eels Anguilla anguilla of the River Rhine, Germany, with special reference to helminth parasites. Parasitology, 119(3):323-330.
Sures B; Lutz I; Kloas W, 2006. Effects of infection with Anguillicola crassus and simultaneous exposure with Cd and 3,3’,4,4’,5-pentachlorobiphenyl (PCB 126) on the levels of cortisol and glucose in European eel (Anguilla anguilla). Parasitology, 132(2):281-288.
Taraschewski H, 2006. Hosts and parasites as aliens. Journal of Helminthology [Environmental and ecological parasitology: the impact of global change. Proceedings of the Black Forest symposium, Freudenstadt, Germany, 7-10 April 2005.], 80(2):99-128.
Taraschewski H; Moravec F; Lamah T; Anders K, 1987. Distribution and morphology of two helminths recently introduced into European eel populations: Anguillicola crassus (Nematoda, Dracunculoidea) and Paratenuisentis ambiguus (Acanthocephala, Tenuisentidae). Diseases of Aquatic Organisms, 3(3):167-176.
Taraschewski H; Renner C; Mehlhorn H, 1988. Treatment of fish parasites 3. Effects of levamisole HCl, metrifonate, fenbenzadole, mebenzadole, and invermectin on Anguillicola crassus (nematodes) pathogenic in the air bladder of eels. Parasitology Research, 74:281-289.
Wielgoss S; Taraschewski H; Meyer A; Wirth T, 2008. Population structure of the parasitic nematode Anguillicola crassus, an invader of declining North Atlantic eel stocks. Molecular Ecology, 17(15):3478-3495. http://www.blackwell-synergy.com/loi/mec
Würtz J; Knopf K; Taraschewski H, 1998. Distribution and prevalence of Anguillicola crassus (Nematoda) in eels Anguilla anguilla of the rivers Rhine and Naab, Germany. Diseases of Aquatic Organisms, 32(2):137-143.
Würtz J; Taraschewski H, 2000. Histopathological changes in the swimbladder wall of the European eel Anguilla anguilla due to infection with Anguillicola crassus. Diseases of Aquatic Organisms, 39:121-134.
Würtz J; Taraschewski H; Pelster B, 1996. Changes in gas composition in the swimbladder of the European eel (Anguilla anguilla) infected with Anguillicola crassus (Nematoda). Parasitology, 112(2):233-238.
Zhang B, 1995. Studies on parasitic diseases in european eel (Anguilla anguilla) arms in Guangdong, China. In: Proceedings of the 10th Anniversary of the Founding of China Parasitological Society [ed. by China, Society of Parasitology of China]. 108-112.
Aguilar A, Álvarez M F, Leiro J M, Sanmartín M L, 2005. Parasite populations of the European eel (Anguilla anguilla L.) in the Rivers Ulla and Tea (Galicia, northwest Spain). Aquaculture. 249 (1/4), 85-94. http://www.sciencedirect.com/science/journal/00448486 DOI:10.1016/j.aquaculture.2005.04.052
Aieta A E, Oliveira K, 2009. Distribution, prevalence, and intensity of the swim bladder parasite Anguillicola crassus in New England and eastern Canada. Diseases of Aquatic Organisms. 84 (3), 229-235. DOI:10.3354/dao02049
Barse A M, McGuire S A, Vinores M A, Eierman L E, Weeder J A, 2001. The swimbladder nematode Anguillicola crassus in American eels (Anguilla rostrata) from middle and upper regions of Chesapeake Bay. Journal of Parasitology. 87 (6), 1366-1370. DOI:10.1645/0022-3395(2001)087[1366:TSNACI]2.0.CO;2
CABI, Undated. CABI Compendium: Status inferred from regional distribution. Wallingford, UK: CABI
CABI, Undated a. CABI Compendium: Status as determined by CABI editor. Wallingford, UK: CABI
Dupont F, Petter A J, 1988. Anguillicola, a multispecific epizootic in Europe. The appearance of Anguillicola crassa (Nematoda, Anguillicolidae) in the European eel, Anguilla anguilla, in Camargue, southern France. (Anguillicola, une épizootie plurispécifique en Europe. Apparition de Anguillicola crassa (Nematoda, Anguillicolidae) chez l'anguille Européenne Anguilla anguilla en Camargue, sud de la France.). Bulletin Français de la Pêche et de la Pisciculture. 38-41. DOI:10.1051/kmae:1988014
Evans D W, Matthews M A, 1999. Anguillicola crassus (Nematoda, Dracunculoidea); first documented record of this swimbladder parasite of eels in Ireland. Journal of Fish Biology. 55 (3), 665-668. DOI:10.1111/j.1095-8649.1999.tb00707.x
Evans D W, Matthews M A, McClintock C A, 2001. The spread of the eel swimbladder nematode Anguillicola crassus through the Erne system, Ireland. Journal of Fish Biology. 59 (5), 1416-1420. DOI:10.1111/j.1095-8649.2001.tb00204.x
Fries L T, Williams D J, Johnson S K, 1996. Occurrence of Anguillicola crassus, an exotic parasitic swimbladder nematode of eels, in south-western United States. Transactions of the American Fisheries Society. 794-797.
Genç E, Șahan A, Altun T, Cengİzler İ, Nevșat E, 2005. Occurrence of the swimbladder parasite Anguillicola crassus (Nematoda, Dracunculoidea) in European eels (Anguilla anguilla) in Ceyhan River, Turkey. Türk Veterinerlik ve Hayvancılık Dergisi. 29 (3), 661-663.
Höglund J, Thomas K, 1992. The black goby Gobius niger as a potential paratenic host for the parasitic nematode Anguillicola crassus in a thermal effluent of the Baltic. Diseases of Aquatic Organisms. 13 (3), 175-180. DOI:10.3354/dao013175
Kennedy C R, Fitch D J, 1990. Colonisation, larval survival and epidemiology of the nematode Anguillicola crassus, parasitic in the eel Anguilla anguilla, in Britain. Journal of Fish Biology. 117-131.
Køie M, 1991. Swimbladder nematodes (Anguillicola spp.) and gill monogeneans (Pseudodactylogyrus spp.) parasitic on the European eel (Anguilla anguilla). Journal de la Conseil International pour Exploration de la Mer. 391-398.
Loukilli A, Belghyti D, 2007. The dynamics of the nematode Anguillicola crassus Kuwahara 1974 in eels Anguilla anguilla (L.1758) in the Sebou Estuary (Morocco). Parasitology Research. 100 (4), 683-686.
Maamouri F, Gargouri L, Ould Daddah M, Bouix G, 1999. Occurrence of Anguillicola crassus (Nematode, Anguillicolidae) in the Ichkeul Lake (Northern Tunisia). Bulletin of the European Association of Fish Pathologists. 19 (1), 17-19.
Maíllo P A, Vich M A, Salvadó H, Marqués A, Gracia M P, 2005. Parasites of Anguilla anguilla (L.) from three coastal lagoons of the River Ebro delta (Western Mediterranean). Acta Parasitologica. 50 (2), 156-160.
Molnár K, 1994. Formation of parasitic nodules in the swimbladder and intestinal walls of the eel Anguilla anguilla due to infections with larval stages of Anguillicola crassus. Diseases of Aquatic Organisms. 20 (3), 163-170.
Moser M L, Patrick W S, Crutchfield J U Jr, 2001. Infection of American eels, Anguilla rostrata, by an introduced nematode parasite, Anguillicola crassus, in North Carolina. Copeia. 848-853. DOI:10.1643/0045-8511(2001)001[0848:IOAEAR]2.0.CO;2
Münderle M, Taraschewski H, Klar B, Chang C W, Shiao J C, Shen K N, He J T, Lin S H, Tzeng W N, 2006. Occurrence of Anguillicola crassus (Nematoda: Dracunculoidea) in Japnese eels Anguilla japonica from a river and an aquaculture unit in SW Taiwan. Diseases of Aquatic Organisms. 101-108.
Nagasawa K, Kim Y G, Hirose H, 1994. Anguillicola crassus and A. globiceps (Nematoda: Dracunculoidea) parasitic in the swimbladder of eels (Anguilla japonica and A. anguilla) in East Asia: a review. Folia Parasitologica. 41 (2), 127-137.
Rolbiecki L, 2008. New data on the introduced exotic nematode Anguillicola crassus Kuwahara, Niimi and Ikagaki, 1974 in the eel Anguilla anguilla in Lake Wdzydze (Polish waters). Oceanological and Hydrobiological Studies. 37 (3), 37-48.
Sasal P, Taraschewski H, Valade P, Grondin H, Wielgoss S, Moravec F, 2008. Parasite communities in eels of the Island of Reunion (Indian Ocean): a lesson in parasite introduction. Parasitology Research. 102 (6), 1343-1350. http://www.springerlink.com/content/k4x12l501gl8504u/?p=57ab614532fd424085eac0de5dfd51c4&pi=31 DOI:10.1007/s00436-008-0916-5
Schabuss M, Kennedy C R, Konecny R, Grillitsch B, Reckendorfer W, Schiemer F, Herzig A, 2005. Dynamics and predicted decline of Anguillicola crassus infection in European eels, Anguilla anguilla, in Neusiedler See, Austria. Journal of Helminthology. 79 (2), 159-167. http://www.ingenta.com/journals/browse/cabi/joh DOI:10.1079/JOH2005281
Schabuss M, Konecny R, Belpaire C, Schiemer F, 1997. Endoparasitic helminths of the European eel, Anguilla anguilla, from four disconnected meanders from the rivers Leie and Scheldt in western Flanders, Belgium. Folia Parasitologica. 44 (1), 12-18.
Sures B, Knopf K, Taraschewski H, 1999. Development of Anguillicola crassus (Dracunculoidea, Anguillicolidae) in experimentally infected Balearic congers Ariosoma balearicum (Anguilloidea, Congridae). Diseases of Aquatic Organisms. 39 (1), 75-78. DOI:10.3354/dao039075
Würtz J, Knopf K, Taraschewski H, 1998. Distribution and prevalence of Anguillicola crassus (Nematoda) in eels Anguilla anguilla of the rivers Rhine and Naab, Germany. Diseases of Aquatic Organisms. 32 (2), 137-143. DOI:10.3354/dao032137
OrganizationsTop of page
Denmark: North European and Baltic Network on Invasive Alien Species (NOBANIS), Web-based service, email@example.com, http://www.nobanis.org/
ContributorsTop of page
04/10/09 Original text by:
Clive Kennedy, University of Exeter, School of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
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