| Ergasilidae | |
|---|---|
 | |
| Ergasilus | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Crustacea |
| Class: | Copepoda |
| Order: | Cyclopoida |
| Suborder: | Ergasilida |
| Family: | Ergasilidae Von Nordmann, 1832 [1] |
| Synonyms [2] | |
Vaigamidae Thatcher & Robertson, 1984 | |
Ergasilidae is a widespread family of copepods and comprises many species. The type genus is Ergasilus . With a few doubtful exceptions all ergasilids are parasitic on fishes. [3]
Various species of Ergasilidae parasitise hosts in various habitats, mostly freshwater, but some attack marine species, especially euryhaline fishes such as mullet. Because the best-known species are adapted to attack the gill filaments of the fishes, Ergasilidae are known by common names such as gill lice. However, some species have been found infesting, and presumably causing, external skin lesions of fish.
Immature instars and mature males of Ergasilidae are fairly typical free-living planktonic copepods. The mature females also can swim competently and at least one species, Ergasilus chautauquaensis, is not known to be parasitic at all. [3] However, that is exceptional; most adult females are parasitic and have morphological adaptations for attacking the gills of host species of fishes.
Though their antennules retain their sensory function, the main second antennae of the adult females are adapted to clinging to the gill filaments of host fishes. In many Ergasilus species it is not clear that mature females are able to release their grip once attached, but when forcibly detached from the host's gills they swim without difficulty.
Another adaptation in parasitic females is that their first legs are armed with heavy, blade-like spines, and in some species the joints also are fused, stiffening them and increasing their effectiveness for harvesting host tissue. Once attached to the gills, the females use their first pair of legs to rasp off gill mucus and tissue and move it forward towards the mouth.
In the genus Ergasilus only the adult females are parasitic. The planktonic males do not venture inside fishes, so fertilisation must take place before the females attach themselves to the host's gills. [3]
Since the Ergasilus females attack the gills of fish, a heavy infestation can cause severe damage and secondary infections, interfere with respiration, and sometimes kill the host. In some fisheries and aquacultural enterprises the mortality and morbidity among fish stocks can present serious economic and ecological problems. [3]
The family Ergasilidae contains the following genera: [2]
Copepods are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic, some are benthic, a number of species have parasitic phases, and some continental species may live in limnoterrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds, puddles, damp moss, or water-filled recesses of plants (phytotelmata) such as bromeliads and pitcher plants. Many live underground in marine and freshwater caves, sinkholes, or stream beds. Copepods are sometimes used as biodiversity indicators.
Tantulocarida is a highly specialised group of parasitic crustaceans that consists of about 33 species, treated as a class in superclass Multicrustacea. They are typically ectoparasites that infest copepods, isopods, tanaids, amphipods and ostracods.
Sea lice are copepods of the family Caligidae within the order Siphonostomatoida. They are marine ectoparasites that feed on the mucus, epidermal tissue, and blood of host fish. The roughly 559 species in 37 genera include around 162 Lepeophtheirus and 268 Caligus species.
Poecilostomatoida are an suborder of copepods. Although it was previously considered a separate order, recent research showed it to be nested within the Cyclopoida
Abergasilus amplexus is a species of parasitic copepod endemic to euryhaline habitats in New Zealand. It is the only known species in the genus Abergasilus.
Bomolochidae is a family of copepods parasitic on marine fishes. Most species parasitize the gills of fish, but some species live in the nostrils or on the eyes of their hosts. The family contains just over 150 species from the following genera:
Ergasilus is a genus of copepod crustaceans occurring in both the ocean and fresh water, often called gill lice. The females are parasitic upon the gills of fishes. Being copepods, gill lice have a single median eye on their head. The second antennae are modified into prehensile pincers. Male gill lice are free-living.
The salmon louse is a species of copepod in the genus Lepeophtheirus. It is a sea louse, a parasite living mostly on salmon, particularly on Pacific and Atlantic salmon and sea trout, but is also sometimes found on the three-spined stickleback. It feeds on the mucus, skin and blood of the fish. Once detached, they can be blown by wind across the surface of the sea, like plankton. When they encounter a suitable marine fish host, they adhere themselves to the skin, fins, or gills of the fish, and feed on the mucus or skin. Sea lice only affect fish and are not harmful to humans.
Oleksandr Prokopovych Markevych was a Ukrainian zoologist, and a prolific helminthologist and copepodologist. He was professor and an Academician of the National Academy of Sciences of Ukraine.
Pennellidae is a family of parasitic copepods. When anchored on a host, they have a portion of the body on the outside of the host, whereas the remaining anterior part of the parasite is hidden inside tissues of the host.
Lernaeocera branchialis, sometimes called cod worm, is a parasite of marine fish, found mainly in the North Atlantic. It is a marine copepod which starts life as a small pelagic crustacean larva. It is among the largest of copepods, ranging in size from 2 to 3 millimetres when it matures as a copepodid larva to more than 40 mm as a sessile adult.
Nicothoë astaci or the 'lobster louse' is an ectoparasitic copepod that parasitises the gills of the European lobster species Homarus gammarus. The lobster louse was first reported in 1826 by Audoin & Milne-Edwards. N. astaci has been found on lobsters inhabiting locations including Scotland, Lundy Island in the Bristol Channel and as far south as France and Portugal. The louse possesses a narrow suctorial mouthpart to feed on host haemolymph. Internally, In its adult form, Nicothoe is barely mobile and most likely remains in the same position for most of its life. The parasite occurs in groups, particularly near the base of the gills, and study has gone into its effects on the lobsters, which are considerably important, commercially. Not much is known about its life cycle, since there are significant gaps in knowledge of certain stages of its growth.
Lernaeopodidae is a family of parasitic copepods. The females are typically large and fleshy, and attach to the host permanently using a plug made of chitin called the bulla. The males cling on to the females using their antennae. They parasitize both marine and freshwater fish. Some lernaeopodids, including Clavella and Salmincola, can have negative impacts on fish in aquaculture.
Pennella is a genus of large copepods which are common parasites of large pelagic fishes. They begin their life cycle as a series of free-swimming planktonic larvae. The females metamorphose into a parasitic stage when they attach to a host and enter into its skin. The males are free swimming. Due to their large size and mesoparasitic life history there have been a number of studies of Pennella, the members of which are among the largest of the parasitic Copepoda. All species are found as adults buried into the flesh of marine bony fish, except for a single species, Pennella balaenopterae which can be found in the muscles and blubber of cetaceans and occasionally other marine mammals, and is the largest species of copepod.
Pennella balaenopterae is a large ectoparasitic copepod specialising in parasitising marine mammals. It is the largest member of the genus Pennella, the other species of which are parasites of larger marine fish.
Lepeophtheirus pectoralis is a species of parasitic copepod from the northeast Atlantic Ocean, and the type species of the genus Lepeophtheirus. It is a parasite of flatfish, with the European flounder, the plaice, and the dab as the most frequent hosts. It feeds on the mucus, skin, and blood of the fish, with egg-producing females infecting the pectoral and pelvic fins of the host, while immature individuals and males are found on the rest of the body.
Lernaeenicus sprattae is a species of copepod in the family Pennellidae. It is a parasite of the European sprat and certain other fish and is sometimes known as the sprat eye-maggot.
Peniculus minuticaudae is a species of parasitic pennellid copepod. It is known from the northeast Pacific Ocean. It was originally described in 1956, redescribed in 2012, and its complete life cycle has been elucidated on the cultured threadsail filefish, Stephanolepis cirrhifer in 2013.
Acanthochondria cornuta is a species of parasitic copepod from the northeast Atlantic Ocean, and the type species of the genus Acanthochondria. It infects the gills of several species of flatfish, particularly the European flounder. Copepodids and immature females infect the holobranch of the host, while adult females prefer the pseudobranch and the internal wall, suggesting they migrate upstream in the gills of the host as they mature.
Ergasilus curticrus is a freshwater parasitic copepod named in 2015. Described from the Orinoco river basin, it was found solely to be hosted by individuals of the Characiform fish species Bryconops giacopinii. Of those located in South America, it is one of only five species in its genus to be found outside of Brazil.
Data related to Ergasilidae at Wikispecies
