Monogenetic trematodes
Are external parasites and fall into the animal kingdom as shown below
Kingdom Animalia
Phylum Platyhelminthes flatworms
Class Trematoda flukes
Subclass Monogenea
Order Monopisthocotylea
Family Gyrodactylidae
Genus Macrogyrodactylus
The genus Macrogyrodactylus is of intrest to Polypterid keepers since three of the genus are known to affect Polypterids,they are listed below
Macrogyrodactylus polypter-malmberg
Macrogyrodactylus polypteri
Macrogyrodactylus simentiensis
Endemic to all inland lakes,rivers and swamps in Africa.Species,also genera, of Monogenea demonstrate a high degree of host specificity,and follow their respective specific fish hosts throughout their range.This fact leads scientists and researchers
to believe as the specific host evolved so did the species specific flukes.
Monogeneans are external flatworms 0.3-2mm in length atttahced to the skin and gills by way of posteriorly positioned attachment organs.They are hermaphrodidic.Members of the family Gyrodactylidae are viviparous; the uterus contains fully formed prenatal offspring.
As mentioned Gyrodactylidae give birth to fully develoed adults.Intra-uterine embryos already contain second and often third generation embryos.An example of how fast some
species reproduce is as follows Gyrodactylus bullatardis on Lebistes reticulatus, from egg to egg at an ambient temperature of 77F80F, is completed within 5460 hours; new specimens first give birth, followed by each subsequent birth, after 18hours.
Eggs develop into embryos ready to be born within 36 to 42 hours (Thurnbull, 1956; Bykhowskii, 1957).
Passage from host to host requires a direct physical contact between the fish (Thurnbull, 1956; Hoffman & Putz, 1964; for detailed description of the reproductive development of Macrogyrodactylus polypteri see Khalil, 1970).
Host fish seem to have a symbiotic relationship with their specific monogeans both in natural condition and in contained enviroments.Even under intense infestations few monogeans are a major health threat with the exception of Gyrodactylids.
Fish heavly infested with Macrogyrodactylus may appear pale due to excess muscus secretion or lack of it.delamination of their scales and localized haemorrhagic lesions and skin erosion this can lead to serious if not fatal bacterial infections.
Khalil (1964) reported fatal hyperinfections (6907340 worms per fish) by Macrogyrodactylus polypteri of aquarium held Polypterus senegalus. Species of Macrogyrodactylus occur in fish with potential for aquaculture in Africa,Spontaneous recovery of P. senegalus from Macrogyrodactylus polypteri infection occurred after two weeks (Khalil, 1964).
Such co-evolutionary relationships are less evident in Gyrodactylids in which species of the same genera (e.g. Gyrodactylus, Macro-gyrodactylus) occur in representatives of
diverse fish families, although individual species, if correctly determined, seem to be narrowly host specific (Malmberg, 1970); this also applies to species infecting African fish (Paperna, 1979). Among species of Polypterus, only P. senegalus succumbed to
massive infestation of Macrogyrodactylus polypteri; all others exposed under similar conditions became only lightly infected (Khalil, 1964).
Crowding fish into culture systems or aquaria often promotes infestation. Introduction of Polypterus senegalus into aquaria caused an exponential increase in infestations with Macrogyrodactylus polypteri, resulting in a worm burden of 6907340 per fish within 2025 days. Natural infections of the same fish species and parasites in the Nile did not exceed 6 worms per single fish (Khalil, 1964). In small habitats and culture systems, the predicted increase in infestation is, however, not always
fulfilled, due to the inhibitive quality of physical (depth, currents, temperatures) and chemical (oxygen, salinities) factors of the environment.
Species of gyrodactylids demonstrate different tolerances to water salinity. Organophosphate -- Masoten (Dipterex, Neguvon, Dylox) is used at a dose of 0.250.50 ppm (A.I.).Quick treatment with a mixture of 2 ppm of 50% DDVP (DP, dichlorovos, Vapona), 0.2 ppm Bromex and 25 ppm Formalin (36% Formaldehyde) for 46 hours has been recommended to clear infestations.Recently the use of products containing Praziquantel has proven effective at clearing infestations.See list below
Jungle labs parasite clear
Jungle labs parasite guard
Hakari prazi pro
Khalil, L., 1964. On the biology of Macrogyrodactylus polypteri Malmberg, 1956,
a monogenetic trematode on Polypterus senegalus in the Sudan. J. Helmith. 38: 219222.
Khalil, L.F., 1970. Further studies on Macrogyrodactylus polypteri, a monogenean on the African freshwater fish Polypterus senegalus. J. Helminth., 44: 329348.
Khalil, L.F., 1971. Checklist of the helminth parasites of African freshwater fishes. Tech. Comm. 42, Comm. Inst. Helm., C.A.B. England, 80pp.
Are external parasites and fall into the animal kingdom as shown below
Kingdom Animalia
Phylum Platyhelminthes flatworms
Class Trematoda flukes
Subclass Monogenea
Order Monopisthocotylea
Family Gyrodactylidae
Genus Macrogyrodactylus
The genus Macrogyrodactylus is of intrest to Polypterid keepers since three of the genus are known to affect Polypterids,they are listed below
Macrogyrodactylus polypter-malmberg
Macrogyrodactylus polypteri
Macrogyrodactylus simentiensis
Endemic to all inland lakes,rivers and swamps in Africa.Species,also genera, of Monogenea demonstrate a high degree of host specificity,and follow their respective specific fish hosts throughout their range.This fact leads scientists and researchers
to believe as the specific host evolved so did the species specific flukes.
Monogeneans are external flatworms 0.3-2mm in length atttahced to the skin and gills by way of posteriorly positioned attachment organs.They are hermaphrodidic.Members of the family Gyrodactylidae are viviparous; the uterus contains fully formed prenatal offspring.
As mentioned Gyrodactylidae give birth to fully develoed adults.Intra-uterine embryos already contain second and often third generation embryos.An example of how fast some
species reproduce is as follows Gyrodactylus bullatardis on Lebistes reticulatus, from egg to egg at an ambient temperature of 77F80F, is completed within 5460 hours; new specimens first give birth, followed by each subsequent birth, after 18hours.
Eggs develop into embryos ready to be born within 36 to 42 hours (Thurnbull, 1956; Bykhowskii, 1957).
Passage from host to host requires a direct physical contact between the fish (Thurnbull, 1956; Hoffman & Putz, 1964; for detailed description of the reproductive development of Macrogyrodactylus polypteri see Khalil, 1970).
Host fish seem to have a symbiotic relationship with their specific monogeans both in natural condition and in contained enviroments.Even under intense infestations few monogeans are a major health threat with the exception of Gyrodactylids.
Fish heavly infested with Macrogyrodactylus may appear pale due to excess muscus secretion or lack of it.delamination of their scales and localized haemorrhagic lesions and skin erosion this can lead to serious if not fatal bacterial infections.
Khalil (1964) reported fatal hyperinfections (6907340 worms per fish) by Macrogyrodactylus polypteri of aquarium held Polypterus senegalus. Species of Macrogyrodactylus occur in fish with potential for aquaculture in Africa,Spontaneous recovery of P. senegalus from Macrogyrodactylus polypteri infection occurred after two weeks (Khalil, 1964).
Such co-evolutionary relationships are less evident in Gyrodactylids in which species of the same genera (e.g. Gyrodactylus, Macro-gyrodactylus) occur in representatives of
diverse fish families, although individual species, if correctly determined, seem to be narrowly host specific (Malmberg, 1970); this also applies to species infecting African fish (Paperna, 1979). Among species of Polypterus, only P. senegalus succumbed to
massive infestation of Macrogyrodactylus polypteri; all others exposed under similar conditions became only lightly infected (Khalil, 1964).
Crowding fish into culture systems or aquaria often promotes infestation. Introduction of Polypterus senegalus into aquaria caused an exponential increase in infestations with Macrogyrodactylus polypteri, resulting in a worm burden of 6907340 per fish within 2025 days. Natural infections of the same fish species and parasites in the Nile did not exceed 6 worms per single fish (Khalil, 1964). In small habitats and culture systems, the predicted increase in infestation is, however, not always
fulfilled, due to the inhibitive quality of physical (depth, currents, temperatures) and chemical (oxygen, salinities) factors of the environment.
Species of gyrodactylids demonstrate different tolerances to water salinity. Organophosphate -- Masoten (Dipterex, Neguvon, Dylox) is used at a dose of 0.250.50 ppm (A.I.).Quick treatment with a mixture of 2 ppm of 50% DDVP (DP, dichlorovos, Vapona), 0.2 ppm Bromex and 25 ppm Formalin (36% Formaldehyde) for 46 hours has been recommended to clear infestations.Recently the use of products containing Praziquantel has proven effective at clearing infestations.See list below
Jungle labs parasite clear
Jungle labs parasite guard
Hakari prazi pro
Khalil, L., 1964. On the biology of Macrogyrodactylus polypteri Malmberg, 1956,
a monogenetic trematode on Polypterus senegalus in the Sudan. J. Helmith. 38: 219222.
Khalil, L.F., 1970. Further studies on Macrogyrodactylus polypteri, a monogenean on the African freshwater fish Polypterus senegalus. J. Helminth., 44: 329348.
Khalil, L.F., 1971. Checklist of the helminth parasites of African freshwater fishes. Tech. Comm. 42, Comm. Inst. Helm., C.A.B. England, 80pp.
