Description
The larval stages (nauplii) and juvenile stages (copepodites), males, and unfertilized females of lernaeid copepods have typical cyclopoid features. The fertilized female undergoes a radical transformation, and becomes an attached worm-like parasite, with few noticeable arthropod features (Grabda 1963; Kabata 1978; Wilson 1916).
Synonymy - Adult females of Lernaea cyprinacea, and other lernaeids, show great plasticity in shape of the holdfast, a principal taxonomic character, according to the host species and the site of attachment. Several previously recognized species have been shown experimentally to be variants in the morphology of L. cyprinacea on different hosts (Demaree 1967; Kabata 1978).
Potentially Misidentified Species - Lernaea cyprinacea is the only species of this genus which we have found reported from natural waters in the Chesapeake Bay region (Deutsch 1977; Haley and Winn 1959). L. cruciata was found on Micropterus salmoides in an aquarium in Washington DC (Reid 1997), while L. pomatidis is known from NC (Burris and Miller 1972). We are aware of only one comprehensive survey of freshwater fish parasites in the Chesapeake Bay watershed (Deutsch 1977, for the Susquehanna River, PA), and none in the tidal waters of the Bay.
Taxonomy
| Kingdom | Phylum | Class | Order | Family | Genus |
|---|---|---|---|---|---|
| Animalia | Crustacea | Copepoda | Cyclopoida | Lernaeidae | Lernaea |
Synonyms
Invasion History
Chesapeake Bay Status
| First Record | Population | Range | Introduction | Residency | Source Region | Native Region | Vectors |
|---|---|---|---|---|---|---|---|
| 1957 | Established | Unknown | Introduced | Unconfirmed | North America | East Asia | Ornamental(Pet Release),Fisheries(Fisheries Accidental) |
History of Spread
Lernaea cyprinacea (Anchor-Worm) was first described from Europe in 1745 under a trinomial name, and was redscribed by Linnaeus in 1758 (Kabata 1978). This freshwater parasitic copepod infects a wide range of teleost fish (100+ species) and also amphibians (Hoffman 1967; Kabata 1978). Consequently, it has been widely spread throughout most of the world with ornamental and stocked fishes. Carassius auratus (Goldfish) may be likeliest vector (Hoffman 1967; Tidd 1934) It is probably native to Asia, including Japan, and has been introduced to mainland Europe, the British Isles (establishment of permanent populations is uncertain), Africa, Australia, and North America (Hall 1983; Hoffman 1967; Kabata 1978; Kennedy 1993).
Lenaea cyprinacea was first reported (as L. carassii) in North America from goldfish farms in OH (1929) and IA (Tidd 1934). Wilson (1918) mentioned it in a global survey of the genus, but did not report it from this continent. Tidd notes: 'If Lernaea carassii were a species native to the United States, it seems strange that it could have so long escaped the attention of fanciers of ornamental fish and fisheries biologists. ... While at present I have records for the occurrence of the 'anchor parasite' in Ohio and Indiana only, I would not be surprised to find that it already has a wide distribution range' (Tidd 1934). Even at this early date, L. cyprinacea was already known from 9 species of fishes (Tidd 1934). Hoffman (1967) cited records from 12 states, including many midwestern states, and MD, CA, WA, and AZ. A search of recent citations in databases adds 7+ states to this list, so L. cyprinacea is probably found in most of North America.
We have no records of this species for tidal waters of Chesapeake Bay, but this may reflect the absence of comprehensive studies of fish parasites in tidal fresh and oligohaline waters. Given the frequent escapes of goldfish into Chesapeake tributaries (Jenkins and Burkhead 1993), and this parasite's apparent lack of host specificity (Kabata 1978), it is probably a regular resident in the Bay.
Potomac River Drainage - Haley and Winn (1959) studied a population in Smith Pond, College Park MD. Nine species of fish, and 30% of individuals were infected with L. cyprinacea, with highest prevalence among Cyprinidae [Cyprinella analostanus (Satinfin shiner, 42%), Cyprinus carpio (Common Carp, 2 of 2 fish infected), Notemigonus chrysoleucas (Golden Shiner, 64%), and Notropus hudsonius (Spottail Shiner, 21%)] and Catostomidae [Catostomus commersoni (White Sucker, 23%) and Eriomyzon oblongus (Fat chubsucker, 50%)]. However, Centrarchidae [Lepomis gibbosus (Pumpkinseed, 8%), Lepomis macrochirus (Bluegill, 5%), and Umbridae [Umbra pygmaea (Eastern mudminnow, 1 of 1 fish)] were also infected.
Susquehanna River Drainage - Deutsch (1977; 1978; 1989) examined fishes of 7 species along the Susquehanna in central PA (Falls to Berwick, Wyoming and Luzerne counties). A general survey of 6 species was done in 1973 (Deutsch 1977), and more specific studies on 2 catostomid fishes in 1973 (Deustsch 1978) and on Esox masquinongy (Muskellunge) in 1984-85 (Deutsch 1989). Lernaea cyprinacea was found on all species, with higher rates of infestation on catostomids [C. commersoni (45-90%); Carpiodes cyprinus (Quillback sucker, 20-27%)] and Esocidae [Esox niger (Chain Pickerel, 38%); Esox masquinongy (Muskellunge, 66%) than in centrarchids [Micropterus dolomieu (Smallmouth Bass, 3%); Pomoxis nigromaculatus (Black Crappie, 4%)] and Percidae [Stizostedion vitreum (Walleye, 3%)] (Deutsch 1977; Deutsch 1978; Deutsch 1989).
History References - Deutsch 1977; Deutsch 1978; Deutsch 1989; Haley and Winn 1959; Hall 1983; Hoffman 1967; Jenkins and Burkhead 1993; Kabata 1978; Kennedy 1993; Tidd 1934; 1918
Invasion Comments
Residency - We have not yet found any specific records of this parasitic copepod in the tidal waters of Chesapeake Bay. However, based on its occurrence and abundance in the Chesapeake watershed, and on this species' wide host range, we expect that L. cyprinacea is a regular resident of tidal fresh and oligohaline waters of Bay tributaries.
Ecology
Environmental Tolerances
| For Survival | For Reproduction | |||
|---|---|---|---|---|
| Minimum | Maximum | Minimum | Maximum | |
| Temperature (ºC) | 0.0 | 36.0 | 20.0 | 36.0 |
| Salinity (‰) | 0.0 | 13.0 | 0.0 | 3.0 |
| Oxygen | ||||
| pH | ||||
| Salinity Range | fresh-oligo |
Age and Growth
| Male | Female | |
|---|---|---|
| Minimum Adult Size (mm) | 3.3 | |
| Typical Adult Size (mm) | 1.1 | 8.6 |
| Maximum Adult Size (mm) | 21.0 | |
| Maximum Longevity (yrs) | 0.8 | |
| Typical Longevity (yrs | 0.1 |
Reproduction
| Start | Peak | End | |
|---|---|---|---|
| Reproductive Season | |||
| Typical Number of Young Per Reproductive Event |
|||
| Sexuality Mode(s) | |||
| Mode(s) of Asexual Reproduction |
|||
| Fertilization Type(s) | |||
| More than One Reproduction Event per Year |
|||
| Reproductive Startegy | |||
| Egg/Seed Form |
Impacts
Economic Impacts in Chesapeake Bay
Economic impacts of Lernaea cyprinacea in tidal waters of Chesapeake Bay are unknown. In the watershed, a high prevalence of parasitism (66%) has been observed on one gamefish, Esox masquinongy (Muskellunge) in the Susquehanna River PA (Deutsch 1989), but the other fishes reported to have high prevalence of L. cyprinacea were suckers and minnows (Deutsch 1977; Deutsch 1978; Haley and Winn 1959). Other gamefishes, such as Lepomis macrochirus (Bluegill), Pomoxis nigromaculatus (Black Crappie), Micropterus dolomieu (Smallmouth Bass), and Stizostedion vitreum (Walleye) had lower incidence of L. cyprinacea, less than 10% of fish infested with adult parasites (Deutsch 1977; Haley and Winn 1959). Parasitism can be lethal to fish, particularly when infestation is heavy, and the parasites, as well as the resulting lesions and tumor-like growths (Khalifa and Post 1976) can make fish unattractive as food or trophies.
Much ornamental fish-farming takes place in the watershed, particularly in Frederick County MD (Terlizzi 1998 personal communication), and L. cyprinacea is likely to be a troublesome pest there, as well as to people who keep Carassius auratus (Goldfish) and Cyprinus carpio (Koi) as ornamentals and pets.
References - Deutsch 1977; Deutsch 1978; Deutsch 1989; Haley and Winn 1959; Khalifa and Post 1976; Terlizzi 1998 perosonal communication
Economic Impacts Outside of Chesapeake Bay
Lernaea cyprinacea is now distributed throughout the temperate and tropical regions of the world, and is known from 100+ species of fishes (Hoffman 1967; Hoffman and Schubert 1984; Kabata 1979). In cultured fish populations, it can be devastating, causing extensive mortality of fishes such as goldfish and carp, as well as unsightly lesions (Khalifa and Post 1976; Tidd 1934). High densities of fish in rearing ponds are likely to greatly favor this and other parasites (Wilson 1918).
While the occurrence of L. cyprinacea in wild fish populations has been frequently studied, its effects on population density, biomass, and structure are poorly known (Eisen 1983). Consequently, its effects on fisheries cannot be quantified. However, high rates of parasitism by L. cyprinacea are likely to detract from the perceived food and sporting qualities of freshwater fish.
References - Eisen 1983; Hoffman 1967; Hoffman and Schubert 1984; Kabata 1979; Khalifa and Post 1976; Tidd 1934; Wilson 1918
Ecological Impacts on Chesapeake Native Species
The abundance of Lernaea cyprinacea in the tidal waters of Chesapeake Bay is unknown, but the parasite was prevalent (infecting up to 60-90% of some host species) at the two locations in the watershed where it has been studied, a pond in College Park MD (Haley and Winn 1959) and the Susquehanna River in central PA (Deutsch 1977; Deutsch 1978; Deutsch 1989). Native hosts observed at these locations include: Esox niger (Chain Pickerel); Umbra pygmaea (Eastern mudminnow); Notemigonus chrysoleucas (Golden Shiner); Notropis analostanus (Satinfin shiner); Notropis hudsonius (Spottail Shiner); Catostomus commersoni (White Sucker); Carpiodes cyprinus (Quillback Sucker); Eriomyzon oblongus (Creek Chubsucker); Lepomis gibbosus (Pumpkinseed) (Deutsch 1977; Deutsch 1978; Haley and Winn 1959). Other species, native to the Chesapeake Bay region, which have been infected experimentally are: Fundulus heteroclitus (Mummichog) (Shields 1968); Rana pipiens (Leopard Frog tadpoles); Rana clamitans (Green Frog tadpoles) (Tidd and Shields 1963).
Parasitism - The occurrence, seasonal abundance, and host preference of Lernaea cyprinacea has been widely studied throughout its range (e.g. Adams 1984; Deutsch 1977; Deutsch 1978; Deutsch 1989; Haley and Winn 1959; Marcogliese 1991; Timmons and Hemstreet 1980). Although L. cyprinacea shows some preference for cyprinids and related families (e.g. Haley and Winn 1959), it is known to feed on more than 100 fish species, as well as the tadpoles of frogs and salmanders (Hoffman 1967; Kabata 1979; Tidd and Shields 1963). Infection of tadpoles with Lernaea have been seen in the field as well as in the laboratory.
In experiments, copepodites of Lernaea cyprinacea favored the fins of Carassius auratus and the mouth and branchial chamber of tadpoles of Rana clamitans and Rana pipiens (Shields and Tidd 1974). However, in field surveys, gill infestations by copepodites are common (e.g., Deutsch 1978; Haley and Winn 1959). Heavy infestations of L. cyprinacea copepodites on the fins can result in fatal inflamation (Shields and Tidd 1974). Heavy infections of copepodites are especially damaging to the gill tissues, causing irritation and necrosis, and can kill the fish through lack of oxygen (Khalifa and Post 1976).
Adult L. cyprinacea can attack any part of the body surface of a fish, but the fins and gills are most frequent sites of attachment (Deutsch 1978; Haley and Winn 1959; Timmons and Hemstreet 1980). The attached transformed adult female penetrates the skin of fishes and becomes deeply imbedded in the host tissue, causing lesions which become hemorrhagic and eventually, necrotic. Muscle bundles near the site of penetration are also destroyed; penetration of the cranium and the walls of the intestine can also occur. The host response includes inflammation and occasionally the development of tumor-like growths around the site of penetration. Secondary bacterial and fungal infections around the lesion are also common (Khalifa and Post 1976). In tadpoles, the anchor of the parasite can affect the kidneys, liver, and spinal cord, as well as the muscle. However, the skin does not show the inflammation and abnormal growth responses characteristic of L. cyprinacea infestation in fishes (Tidd and Shields 1963). Parasitism by L. cyprinacea frequently causes mortality in fishes and tadpoles, particularly in smaller individuals. This may vary with the site of penetration, among other factors (Khalifa and Post 1976). However, parasitized fish are capable of rejecting adult parasites, even after host penetration. The host's ability to do this is highly variable, and may depend on immunological history and overall health (Shields and Goode 1978).
While Lernaea cyprinacea has been extensively studied in terms of prevalence and pathology, and it is known as a serious pest in aquaculture situations, its impact on the density, biomass, and age-structure of natural fish populations is not well understood. Parasitism by L. cyprinacea did not influence mortality due to predation in parasitized Pimephales promelas (Fathead Minnow) exposed to Walleye (Stizostedion vitreum) and Northern Pike (Esox lucius) (Vaughan and Coble 1975). In many natural populations, while a high percentage of fish are infested, most have only one parasite. Eisen (1983) has modelled the mortality as a function parasite of prevalence, parasites per fish, and the proportion of a fish's surface which is 'critical', where penetration is likely to be lethal. He argues that the parasite population is regulated by the mortality of the host, but that parasite density does not regulate the host population (Eisen 1983). However, empirical studies of natural populations of the host and parasite have not been conducted.
References - Adams 1984; Deutsch 1977; Deutsch 1978; Deutsch 1989; Eisen 1983; Haley and Winn 1959; Hoffman 1967; Kabata 1979; Khalifa and Post 1976; Marcogliese 1991; Shields and Goode 1978; Tidd and Shields 1963; Timmons and Hemstreet 1980; Vaughan and Coble 1975
Ecological Impacts on Other Chesapeake Non-Native Species
Cyprinus carpio (Common Carp) and Carassius auratus (Goldfish) are very frequently hosts of Lernaea cyprinacea (Eisen 1983; Kabata 1979; Tidd 1934), although we have not found published records in the Chesapeake watershed. Introduced species reported as having been parasitized in Smith Pond, College Park MD (Haley and Winn 1959) and the Susquehanna River, Central PA (Deutsch 1977; Deutsch 1978; Deutsch 1989) are: Esox masquinongy (Muskellunge); Lepomis macrochirus (Bluegill); Micropterus dolomieu (Smallmouth Bass); Stizostedion vitreum (Walleye).
Parasitism - General impacts of Lernaea cyprinacea's parasitism of fishes are discussed under 'Ecological Impacts on Resident Species'. This parasite appears to be more likely to be lethal under hatchery, aquaculture, or ornamental conditions where fish are likely to be crowded together (Tidd 1934; Eisen 1983).
References - Deutsch 1977; Deutsch 1978; Deutsch 1989; Eisen 1983; Haley and Winn 1959; Kabata 1979; Tidd 1934
References
Adams, Ann M. (1984) Infestation of Fundulus kansae (Garman) (Pisces: Cyprinodontidae) by the copepod Lernaea cyprinacea Linnaeus, 1758, in the South Platte River, Nebraska., American Midland Naturalist 112: 131-137Burris, Kenneth Wayne; Miller, Grover C. (1972) Parasitic copepods of some freshwater fishes from North Carolina, Journal of the Elisha Mitchell Scientific Society 88: 18-20
Demaree, Richard S., Jr. (1967) Ecology and external morphology of Lernaea cyprinacea., American Midland Naturalist 78: 416-427
Deutsch, Wiliam G. (1978) Lernaea cyprinacea on two catostomid fishes., Proceedings of the Pennsylvania Academy of Science 52: 57-59
Deutsch, William G. (1977) Fish parasites from the Susquehanna River in Pennsylvania, with new host records, Proceedings of the Pennsylvania Academy of Science 51: 122-124
Deutsch, William G. (1984) Parasites of Susquehanna River (Pennsylvania) Muskellunge, Journal of the Pennsylvania Academy of Science 63: 25-27
Eisen, Stanley (1983) An alternative model based on random distributions for density-dependent regulation in host-parasitic systems., American Midland Naturalist 109: 230-239
Grabda, Jadwiga (1963) Life cycle and morphogenesis of Lernaea cyprinacea L., Parasitologica Polonica 11: 169-199
Haley, A. James; Winn, Howard E. (1959) Observations on a lernaean parasite of freshwater fishes, Transactions of the American Fisheries Society 88: 128-129
Hall, D. N. (1983) Occurrence of the copepod parasite Lernaea cyprinacea L., on the Australian grayling, Prototroctes maraena Gunther., Proceedings of the Royal Society of Victoria 95: 273-274
Hoffman, Glenn L. (1967) Parasites of North American freshwater fishes, In: (Eds.) . , Berkeley. Pp.
Hoffman, Glenn, L.; Schubert, Gottfried (1984) Some parasites of exotic fishes., , Baltimore, MD. Pp. 233-261
Jenkins, Robert E.; Burkhead, Noel M. (1993) Freshwater fishes of Virginia., , Bethesda, MD. Pp.
Jones, Philip W.; Martin, F. Douglas; Hardy, Jerry D., Jr. (1978) Development of fishes of the mid-Atlantic Bight. V. 1. Acipenseridae through Ictaluridae., In: (Eds.) . , Washington DC. Pp.
Kabata, Z. (1979) Parasitic Copepoda of British Fishes, , London. Pp.
Kennedy, C. R. (1993) Introductions, spread, and colonization of new localities by fish helminth and crustacean parasites in the British Isles: A perspective and appraisal, Journal of Fish Biology 43: 287-301
Khalifa A.; Post, George (1976) Histopathological effect of Lernaea cyprinacea (a copepod parasite) on fish, Progressive Fish Culturist 38: 110-113
Marcogliese, David J. (1991) Seasonal occurrence of Lernaea cyprinacea on fish in Belews Lake, North Carolina., Journal of Parasitology 77: 326-327
Page, Lawrence M.; Burr, Brooks M. (1991) Freshwater Fishes., , Boston. Pp.
1997 Checklist of the Copepoda (Crustacea) of the District of Colombia. http://www.im.nbs.gov/biocopewash.html
Shields, Robert J., Sperber, Robert G. (1974) Osmotic regulation of Lernaea cyprinacea L. (Copepoda), Crustacean 26: 157-172
Shields, Robert J., Tidd, Wilbur M. (1968) Site selection on hosts by copepodids of Lernaea cyprinacea L. (Copepoda)., Crustacean 1: 88-94
Shields, Robert J.; Goode, Robert P. (1978) Host rejection of Lernaea cyprinacea L. (Copepoda), Crustacean 35: 301-307
Terlizzi, Daniel E. (1996) Toward regional management of aquatic nuisance species in the Chesapeake Bay basin, Aquatic Nuisance Species Digest 1: 38, 46-47
Tidd, Wilbur M.; Shields, Robert J. (1963) Tissue damage inflicted by Lernaea cyprinacea Linnaeus, a copepod parasitic on tadpoles, The Journal of Parasitology 49: 693-696
Tidd, Wilbur, M, (1934) Recent infestations of goldfish and carp by the 'anchor parasite,' Lernaea cyprinacea., Transactions of the American Fisheries Society 64: 176-180
Timmons, T. J.; Hemstreet, W. G. (1980) Prevalence rate of Lernaea cyprinacea L. (Copepoda: Lernaeidae) on young-of-the-year largemouth bass, Micropterus salmoides (Lacepede), in West Point Resevoir, Alabama-Georgia, U.S.A., Journal of Fish Diseases 3:
Vaughan, Gene E.; Coble, Daniel W. (1975) Sublethal effects of three ectoparasites on fish, Journal of Fish Biology 7: 283-294
Wilson, Charles Branch (1918) Economic relations, anatomy, and life history of the genus Lernaea., Bulletin of the United States Bureau of Fisheries 35: 163-195