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2. A new species of Taeniacanthus (Copepoda: Taeniacanthidae) parasitic on two pufferfish species, Marilyna meraukensis and M. darwinii (Teleostei: Tetraodontidae), from Australia
- Creator:
- Tang, Danny
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fish parasite, taxonomy, pufferfish, and parasitic copepod
- Language:
- English
- Description:
- A new species of Taeniacanthidae (Copepoda, Cyclopoida), Taeniacanthus kiemae sp. n., is described based on adult female and male specimens collected from the branchial cavity wall of Marilyna meraukensis (de Beaufort) and M. darwinii (Castelnau) (Teleostei, Tetraodontidae) caught in Australian waters. The new species differs from its congeners by having the following combination of characters in the adult female: 1) maxilla armed with a stout terminal process and two small elements; 2) multiple rows of spinules on the large pectinate process of the antenna; 3) an extremely long and thin maxilliped claw; 4) second exopodal segment of leg 1 with eight setae; 5) third exopodal segment of leg 3 with three spines and four setae; 6) third exopodal segment of leg 4 with three spines and two setae; and 7) each spine on the free exopodal segment of leg 5 with a subterminal flagellum. Taeniacanthus kiemae is the second copepod species reported from M. meraukensis and M. darwinii and the first taeniacanthid species reported from pufferfishes in Australia.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Anuretes grandis sp. п., a caligid copepod (Siphonostomatoida) parasitic on Diagramma pictum (Pisces) in Taiwan, with discussion of Anuretes Heller, 1865
- Creator:
- Ju-shey, Ho and Ching-Long, Lin
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- fish parasite, parasitic copepod, Taiwan, Anuretes grandis, taxonomy, and key to species
- Language:
- English
- Description:
- A new species of caligid copepod (Siphonostomatoida), Anuretes grandis sp. п., parasitic on the painted sweetlips [Diagrammapictum (Thunberg)] in Taiwan is described. The new species is distinguished from its congeners by having: (1) free margin of céphalothorax not covering fourth pediger, (2) large genital complex longer than 2/3 of the cephalic shield, (3) no maxillary whip, (4) leg 3 with 9 setae on the terminal segment of exopod and 8 plumose setae on the terminal segment of endopod, and (5) armature of I,III on leg 4 exopod. Genus Anuretes Heller, 1865 is reviewed and redefined. Based on the new diagnosis three species (A. chelatus Prahha et Pillai, A. fedderni Price and A. parvulus Wilson) were transferred to Pseudanureles, and two species (A.furcatus Capart and A. renalis Ileegaard) were transferred to Lepeophtheirus. In addition, the following three species of caligids were transferred to Anuretes: Lepeophtheirus fallolunulus Lewis, Heniochophilus indicus Pillai, and Lepeophtheirus rotundigenitalis Prabha et Pillai. The latter is renamed Anuretes occullus nom. n. due to the homonym encountered through this transfer. “Anuretes plectorhynchi Yamaguti” reported by Prabha and Pillai (1986) is renamed Anuretes similis sp. n. and Anuretes yamagutii Prabha et Pillai is relegated to the synonym of Anuretes anomalus Pillai. A key to the 18 species of Anuretes is provided.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Aspects of the morphology and a review of the taxonomic status of three species of the genus Chonopeltis (Crustacea: Branchiura) from the Orange-Vaal and South West Cape River Systems, South Africa
- Creator:
- Van As, Liesl L. and Van As, Jo G.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Chonopeltis australis, Chonopeltis minutus, Chonopeltis australissimus, taxonomy, morphology, and fish parasite
- Language:
- English
- Description:
- Comparative scanning electron microscopical studies were carried out on Chonopeltis australis Boxshall, 1976 collected from different localities in the Orange-Vaal River System in South Africa and on material of Chonopeltis minutus Fryer, 1977 and Chonopeltis australissimus Fryer, 1977 on loan from the Albany Museum, Grahamstown. This elucidates the fine structure of morphological features, which are of taxonomic importance and illustrates the significance of the copulatory structures on the legs as a taxonomic tool. It was also concluded that C. australissimus is the same as C. minutus, with C. australissimus the junior synonym.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Chonopeltis liversedgei sp. n. (Crustacea: Branchiura), parasite of the Western bottlenose Mormyrus lacerda (Mormyridae) from the Okavango Delta, Botswana
- Creator:
- Van As, Jo G. and Van As, Liesl L.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Chonopeltis liversedgei, morphology, taxonomy, and fish parasite
- Language:
- English
- Description:
- A new species Chonopeltis liversedgei sp. n. of the endemic African genus Chonopeltis Thiele, 1900 (Crustacea: Branchiura) is described. T his ectoparasite inhabits the branchial chamber of its mormyrid host Mormyrus lacerda Castelnau, 1861 and was collected from three localities in the Okavango River and its inland Delta in Botswana, Southern Africa.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Different hosts in different lakes: prevalence and population genetic structure of plerocercoids of Ligula intestinalis (Cestoda) in Czech water bodies
- Creator:
- Nazarizadeh, Masoud, Peterka, Jiří, Kubečka, Jan, Vašek, Mojmír, Jůza, Tomáš, Ribeiro de Moraes, Karlos, Čech, Martin, Holubová, Michaela, Souza, Allan T., Blabolil, Petr, Muška, Milan, Tsering, Lobsang, Bartoň, Daniel, Říha, Milan, Šmejkal, Marek, Tušer, Michal, Vejřík, Lukáš, Frouzová, Jaroslava, Jarić, Ivan, Prchalová, Marie, Vejříková, Ivana, and Štefka, Jan
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- tapeworm, Czech Republic, host specificity, freshwater, and fish parasite
- Language:
- English
- Description:
- Ligula intestinalis (Linnaeus, 1758) is a tapeworm parasite with a worldwide distribution that uses a wide variety of fish species as its second intermediate host. In the present study, we investigated the prevalence and population genetic structure of plerocercoids of L. intestinalis in five common cyprinoid species, roach Rutilus rutilus (Linnaeus), freshwater bream Abramis brama (Linnaeus), white bream Blicca bjoerkna (Linnaeus), bleak Alburnus alburnus (Linnaeus), and rudd Scardinius erythrophthalmus (Linnaeus), collected in six water bodies of the Czech Republic (Milada, Most, Medard, Jordán, Římov and Lipno). Of the six study sites, the highest frequency of parasitism was recorded in Lake Medard (15%). The overall prevalence rate among the species was as follows: roach > rudd ≥ freshwater bream > bleak > white bream. Two mitochondrial genes (cytb and COI) were used to compare the population genetic structure of parasite populations using selected samples from the five fish species. The results of the phylogenetic analysis indicated that all populations of L. intestinalis were placed in Clade A, previously identified as the most common in Europe. At a finer scale, haplotype network and PCoA analyses indicated the possible emergence of host specificity of several mtDNA haplotypes to the freshwater bream. Moreover, pairwise Fixation indices (FST) revealed a significant genetic structure between the parasite population in freshwater bream and other host species. Parasite populations in roach not only showed the highest rate of prevalence but also depicted a maximum number of shared haplotypes with populations from bleak and rudd. Our results suggest that recent ecological differentiation might have influenced tapeworm populations at a fine evolutionary scale. Thus, the differences in prevalence between fish host species in different lakes might be influenced not only by the parasite's ecology, but also by its genetic diversity.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Infection dynamics of the monogenean parasite Gyrodactylus gasterostei on sympatric and allopatric populations of the three-spined stickleback Gasterosteus aculeatus
- Creator:
- Raeymaekers, Joost A. M., Wegner, K. Mathias, Huyse, Tine, and Volckaert, Filip A. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Monogenea, Gyrodactylus gasterostei, ecological immunity, fish parasite, Gasterosteus aculeatus, host specificity, local adaptation, and parasite-host coevolution
- Language:
- English
- Description:
- Parasites with high host specificity maximally depend on their hosts, which should increase the likelihood of coevolution. However, coevolution requires reciprocal selection exerted by the host and the parasite, and thus a considerable level of parasite virulence. In species of the monogenean ectoparasite genus Gyrodactylus consecutive generations are confronted with a single host, which may constrain the evolution of virulence. Transmission, which is often important in the ecology of Gyrodactylus species, may have the opposite effect, but may also lead to the avoidance of coevolutionary arms races. We investigated the potential outcome of coevolution between Gyrodactylus gasterostei Gläser, 1974 and its host, the three-spined stickleback (Gasterosteus aculeatus L.) by determining the strength of genotype by genotype (G×G) interactions on two levels: within and between sympatric and allopatric host populations. To do so, we compared the parasite's infection dynamics on laboratory-reared sympatric (Belgian) and allopatric (German) hosts. We found that a parasite line successfully infected a range of sympatric host genotypes (represented by families), while it failed to establish on allopatric hosts. Phylogeographic studies suggest that neutral genetic divergence between the host populations cannot explain this dramatic difference. Provided that this result can be generalised towards other parasite lines, we conclude that coevolution in this host-parasite system is more likely to lead to local adaptation on the population level than to G×G interactions within populations.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Lepeophtheirus simplex sp. n., a caligid copepod (Siphonostomatoida) parasitic on ''botete'' (bullseye puffer, Sphoeroides annulatus) in Sinaloa, Mexico
- Creator:
- Ho, Ju-shey, Gómez, Samuel, and Fajer-Avila, Emma
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Lepeophtheirus simplex, fish parasite, parasitic copepod, Caligidae, and Mexico
- Language:
- English
- Description:
- A new species of caligid copepod, Lepeophtheirus simplex sp. n., parasitic on bullseye puffer, Sphoeroides annulatus (Jenyns) in Sinaloa, Mexico is described. The new species is distinguished from its congeners by the possession of (1) a maxillule with simple dentiform process; (2) a sternal furca with sharply pointed, curved tines; (3) a 2-segmented exopod of leg 3 with simple, slender spine on proximal segment; (4) a 3-segmented exopod of leg 4 with a long proximal, outer spine; and (5) the terminal claw of male antenna with a large, tridentate, medial protuberance.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Life cycle of the temporary fish parasite, Gnathia africana (Crustacea: Isopoda: Gnathiidae)
- Creator:
- Smit, Nico J., Basson, Linda, and Van As, Jo G.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Isopoda, Gnathiidae, Gnathia africana, life cycle, and fish parasite
- Language:
- English
- Description:
- Laboratory work was conducted to elucidate the life cycle of the South African gnathiid isopod, Gnathia africana Barnard, 1914. The natural fish hosts of this temporary parasite, the super klipfish Clinus superciliosus (Linnaeus, 1758), were exposed to gnathiid larvae in the laboratory. It was found that G. africana has three larval stages, consisting of three unfed (zuphea) and three fed (praniza) stages. First-, second- and third-stage zuphea larvae took an average of 2 h 18 min, 2 h 43 min and 10 h 8 min respectively to complete their feeding and the first- and second-stage praniza moulted at 8 and 10 days respectively into the next zuphea stage. Three to six days after its last blood meal, the sex of the third and final praniza stage could be determined by the presence of either a testis or two ovaries in the dorsal pereon. Male larvae moulted into adult males between 8 and 10 days post feeding. Female larvae moulted at approximately 17 days into adult females. Fertilisation of the eggs by the male took place within 24 hours of completion of the female moult. The development of the embryos and subsequent release of the young larvae between 15 and 23 days post fertilisation completed the cycle. This entire cycle took approximately 62 days in water temperatures of 20-25°C.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10. Occurrence of cystacanths of Polyacanthorhynchus kenyensis larvae (Acanthocephala) in four teleostean fishes from a tropical lake, Lake Naivasha, Kenya
- Creator:
- Aloo, P. A. and Dezfuli, B. S.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- acanthocephalan, seasonal patterns, fish parasite, tropical lake, and Kenya
- Language:
- English
- Description:
- From January 1992 to December 1993, a total of 2158 fish, namely Oreochromis leucostictus (Trewavas, 1983), Mi-cropterus salmoides (Lacépède, 1802), I'ilapiu zillii (Gervais, 1848) and Barhus amphigrama (Boulenger, 1902) were sampled from thirteen stations on Lake Naivasha, Kenya, using a fleet of gill nets and examined for helminth parasites. The prevalence of infection due to cystacanths of an acanthocephalan, Polyacanthorhynchus kenyensis Schmidt et Canaris, 1967 among parasitized O. leucostictus ranged from 30.4 to 86.9%; among T. zillii from 4.1 to 77.7%; in M. salmoides from 20 to 50%; and in B. amphi grama from 5.8 to 100%. In 735 hosts belonging to the above four species, a total of 4198 immature specimens of P. kenyensis were recovered. All cystacanths were found in extraintestinal sites, either free within the fish body cavity or encysted within the host visceral organs. There was no significant variation in the prevalence of the parasite within months (P > 0.001). Host sex ratio was significant (P < 0.001 ) in favour of male T. zillii, and also highly significant (P < 0.001 ) in favour of male O. leucostictus. Moreover, in this fish, prevalence of infection was observed to increase with the increase in the size of the fish. Among infected M. salmoides, there was no significant departure from a 1 : 1 sex ratio.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public