Monogenea (Platyhelminthes), mainly gill and fin ectoparasites of fish, are often recognized as host specific and morphologically and ecologically diverse. These parasites exhibit high species diversity at the level of host species or individual fish specimens. Using case studies, especially those widely performed in Dactylogyrus parasitizing cyprinoid fish, this article presents current knowledge on the ecology and evolution of congeneric gill monogeneans. The important aspects of the ecology of congeneric monogeneans are highlighted, in particular: host specificity expressed at several host levels (from strict specificity to phylogenetic specificity), microhabitat specificity expressed by restricted positions on fish gills to facilitate intraspecific mating, and the link between microhabitat preference and morphological adaptation (i.e., sclerotized structures of the haptor) or reproductive isolation. From the evolutionary perspective, this study focused on the processes of the speciation and diversification of congeneric monogeneans, highlighting the role of host switch as the most prominent coevolutionary event, accompanied in some cases mostly by intrahost speciation or cospeciation, as revealed by cophylogenetic studies. Here, important knowledge on evolutionary patterns of host specificity, microhabitat specificity, and morphological adaptation is presented. Host-specific monogeneans may represent an important tool for studying the historical biogeography of their hosts. Specifically, in the case of freshwater fish hosts exhibiting disjunctive distribution, they reflect both historical and contemporary contacts. The role of host-specific congeneric monogeneans in revealing historical intercontinental and intracontinental contacts between freshwater fish is highlighted. Finally, the importance of the role of genetic coadaptation, limiting the presence of host-specific monogeneans in hybrid fish, is emphasized.

TITLE: Monogènes spécifiques à leur hôte parasitant les poissons d’eau douce : écologie et évolution des associations hôtes-parasites. ABSTRACT: Les Monogènes (Plathelminthes), principalement ectoparasites des branchies et des nageoires des poissons, sont souvent reconnus comme spécifiques à leur hôte et diversifiés morphologiquement et écologiquement. Ces parasites présentent une grande diversité d’espèces au niveau des espèces hôtes ou des spécimens individuels de poissons. À l’aide d’études de cas (en particulier celles largement réalisées chez les Dactylogyrus parasitant les poissons cyprinoïdes), les connaissances actuelles sur l’écologie et l’évolution des monogènes branchiaux congénères sont présentées. Les aspects importants de l’écologie des monogènes congénères sont mis en évidence, en particulier la spécificité à l’hôte exprimée à plusieurs niveaux de l’hôte (de la spécificité stricte à la spécificité phylogénétique), la spécificité du microhabitat exprimée par des positions restreintes sur les branchies des poissons pour faciliter l’accouplement intraspécifique, et le lien entre la préférence du microhabitat et l’adaptation morphologique (c’est-à-dire les structures sclérifiées du hapteur) ou l’isolement reproductif. Du point de vue évolutif, l’étude a été concentrée sur les processus de spéciation et de diversification des monogènes congénères, soulignant le rôle du changement d’hôte comme l’événement coévolutif le plus important, accompagné surtout dans certains cas de spéciation ou de cospéciation intra-hôte, comme le révèlent les études cophylogénétiques. Des connaissances importantes sont présentées ici sur les modèles évolutifs de spécificité d’hôte, de spécificité de microhabitat et d’adaptation morphologique. Les monogènes spécifiques à l’hôte peuvent représenter un outil important pour étudier la biogéographie historique de leurs hôtes. Plus précisément, dans le cas des poissons d’eau douce hôtes présentant une distribution disjonctive, ils reflètent à la fois des contacts historiques et contemporains. Le rôle des monogènes congénères spécifiques à leur hôte dans la révélation des contacts intercontinentaux et intracontinentaux historiques entre poissons d’eau douce est mis en évidence. Enfin, l’importance du rôle de la coadaptation génétique limitant la présence de monogènes spécifiques à l’hôte chez les poissons hybrides est soulignée.

• Klíčová slova
• Fish parasites, Genetic coadaptation, Host specificity, Host-parasite coevolution, Monogeneans, Species coexistence,
• MeSH
• biologická evoluce * MeSH
• druhová specificita MeSH
• ekosystém MeSH
• fylogeneze MeSH
• hostitelská specificita * MeSH
• infekce červy třídy Trematoda veterinární   parazitologie   MeSH
• interakce hostitele a parazita * MeSH
• nemoci ryb * parazitologie   MeSH
• ploštěnci fyziologie   klasifikace   genetika   izolace a purifikace   MeSH
• ryby parazitologie   MeSH
• sladká voda * parazitologie   MeSH
• Trematoda fyziologie   klasifikace   genetika   MeSH
• žábry * parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Coevolutionary processes that drive the patterns of host-parasite associations can be deduced through congruence analysis of their phylogenies. Feather lice and their avian hosts have previously been used as typical model systems for congruence analysis; however, such analyses are strongly biased toward nonpasserine hosts in the temperate zone. Further, in the Afrotropical region especially, cospeciation studies of lice and birds are entirely missing. This work supplements knowledge of host-parasite associations in lice using cospeciation analysis of feather lice (genus Myrsidea and the Brueelia complex) and their avian hosts in the tropical rainforests of Cameroon. Our analysis revealed a limited number of cospeciation events in both parasite groups. The parasite-host associations in both louse groups were predominantly shaped by host switching. Despite a general dissimilarity in phylogeny for the parasites and hosts, we found significant congruence in host-parasite distance matrices, mainly driven by associations between Brueelia lice and passerine species of the Waxbill (Estrildidae) family, and Myrsidea lice and their Bulbul (Pycnonotidae) host species. As such, our study supports the importance of complex biotic interactions in tropical environments.

• Klíčová slova
• cospeciation, feather lice, host switching, host–parasite associations, passerines, tropical ecology,
• Publikační typ
• časopisecké články MeSH

Host-parasite coevolution is one of the fundamentals of evolutionary biology. Due to the intertwined evolutionary history of two interacting species and reciprocal coadaptation processes of hosts and parasites, we can expect that studying parasites will shed more light onto the evolutionary processes of their hosts. Monogenea (ectoparasitic Platyhelminthes) and their cyprinoid fish hosts represent one of the best models for studying host-parasite evolutionary relationships using a cophylogenetic approach. These parasites have developed remarkably high host specificity, where each host species often serves as a potential host for its own host-specific monogenean species. Here, the cophylogenetic relationships in the Dactylogyrus-Squalius system was investigated, as Squalius is one of several cyprinoid genera with puzzling phylogeography and inhabits all four major peri-Mediterranean peninsulas. Of 29 endemic Squalius species examined for the presence of Dactylogyrus parasites, a total of 13 Dactylogyrus species were collected from the gills of 20 Squalius species across a wide range of distribution. Phylogenetic reconstruction revealed a polyphyletic origin for Dactylogyrus species parasitizing congeneric Squalius, with four major clades being recognized. On the basis of the delimitation of host specificity, strict specialists parasitizing single host species, geographic specialists parasitizing congeners in a limited geographical region, and true generalists parasitizing congeners in various geographical regions were recognized in Dactylogyrus species parasitizing Squalius. The phylogenetic reconstruction of Squalius hosts revealed two major clades, the first encompassing only peri-Mediterranean species and the second including species from other Euro-Asian regions. Distance-based cophylogenetic methods did not reveal a statistically significant global cophylogenetic structure in the studied system; however, several host-parasite links among Iberian endemic species contributed significantly to the overall structure. The widest host range and associated genetic variability were recorded for D. folkmanovae, parasitizing nine Squalius species, and D. vistulae, parasitizing 13 Squalius species. Two different dispersion mechanisms and morphological adaptations to Squalius hosts were clearly reflected in the contrasting cophylogenetic patterns for these two species with different levels of host specificity. While host-parasite cospeciation plays an important role in diversification within D. folkmanovae, diversification within D. vistulae is driven mainly by host switching.

• Klíčová slova
• Cophylogeny, Cyprinoidei, Dactylogyrus, Host specificity, Host-switching, Peri-Mediterranean, Squalius,
• MeSH
• Cyprinidae * genetika   MeSH
• fylogeneze MeSH
• interakce hostitele a parazita genetika   MeSH
• paraziti * MeSH
• ploštěnci * genetika   MeSH
• Trematoda * genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Exploration of interactions between hosts and parasitic symbionts is important for our understanding of the temporal and spatial distribution of organisms. For example, host colonization of new geographical regions may alter levels of infections and parasite specificity, and even allow hosts to escape from co-evolved parasites, consequently shaping spatial distributions and community structure of both host and parasite. Here we investigate the effect of host colonization of new regions and the elevational distribution of host-parasite associations between birds and their vector-transmitted haemosporidian blood parasites in two geological and geographical settings: mountains of New Guinea and the Canary Islands. Our results demonstrate that bird communities in younger regions have significantly lower levels of parasitism compared to those of older regions. Furthermore, host-parasite network analyses demonstrate that blood parasites may respond differently after arriving to a new region, through adaptations that allow for either expanding (Canary Islands) or retaining (New Guinea) their host niches. The spatial prevalence patterns along elevational gradients differed in the two regions, suggesting that region-specific biotic (e.g., host community) and abiotic factors (e.g., temperature) govern prevalence patterns. Our findings suggest that the spatiotemporal range dynamics in host-parasite systems are driven by multiple factors, but that host and parasite community compositions and colonization histories are of particular importance.

• Klíčová slova
• Canary Islands, New Guinea, avian malaria, elevational gradients, haemosporidians,
• MeSH
• časoprostorová analýza MeSH
• Haemosporida * MeSH
• interakce hostitele a parazita * MeSH
• ptáci parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Nová Guinea MeSH
• Španělsko MeSH

Louse flies (Hippoboscidae) are permanent ectoparasites of birds and mammals. They have a cosmopolitan distribution with more than 200 described species. The aim of this study was to reveal host-vector-parasite associations between louse flies, birds, and trypanosomes. A total of 567 louse fly specimens belonging to 7 species were collected from birds at several localities in Czechia, including the rare species Ornithophila metallica and Ornithoica turdi. There was a significant difference in the occurrence of Ornithomya avicularia and Ornithomya fringillina on bird hosts according to their migratory status, O. fringillina being found more frequently on long-distance migrants. Trypanosomes were found in four species, namely, Ornithomya avicularia, O. fringillina, O. biloba, and Ornithoica turdi; the later three species are identified in this paper as natural trypanosome vectors for the first time. The prevalence of trypanosomes ranged between 5 and 19%, the highest being in O. biloba and the lowest being in O. fringillina. Phylogenetic analysis of the SSU rRNA gene revealed that a vast majority of trypanosomes from hippoboscids belong to the avian T. corvi/culicavium group B. Four new lineages were revealed in group B, with louse flies being probable vectors for some of these trypanosome lineages. We also confirmed the transcontinental distribution of several trypanosome lineages. Our results show that hippoboscids of several genera are probable vectors of avian trypanosomes.

• Klíčová slova
• Hippoboscidae, Ornithoica, Ornithomya, Ornithophila, Trypanosoma, avian parasite, host specificity, transmission,
• Publikační typ
• časopisecké články MeSH

As host community diversity decreases, parasite diversity may also decline. The life cycles of trematodes involve multiple hosts from different orders, with many trematodes displaying narrow host specialization. In the 1960s and 2010s, we performed full-body necropsies of juvenile or first-year birds of four wetland bird species, Anas platyrhynchos, Aythya fuligula, Fulica atra, and Chroicocephalus ridibundus which originated from the southern Czech Republic, and examined them for the presence of trematodes. We compared the trematode species richness and diversity of the analyzed component communities. We found complete disintegration of host-parasite networks, which led to declining populations and local extinctions of the majority of trematode species, particularly those with narrow host preferences. For example, in black-headed gulls, 67% of trematode species recorded in the 1960s were absent in gulls that were examined in the 2010s. In contrast, we did not identify any trematode species that were absent in the 1960s but present in the 2010s. This collapse provides new insight into the recent debate regarding whether human-caused extinctions should be considered a problem when locally extinct host species are replaced by an equal or even higher number of nonnative species, thus maintaining local alpha diversities but leading to biotic homogenization and consequently reducing beta diversity. By documenting the collapse of the host-parasite network, we provide a strong argument that biodiversity cannot be assessed by simple measures alone, as only local-scale conservation measures allow the preservation of host-pathogen interactions and nutrient cycles and thus prevent the loss of low-visibility species, such as helminths.

• Klíčová slova
• Aquaculture, Fishponds, Helminths, Sustainability, Trematoda, Wetlands,
• MeSH
• biodiverzita MeSH
• Charadriiformes parazitologie   MeSH
• extinkce biologická * MeSH
• interakce hostitele a parazita MeSH
• kachny parazitologie   MeSH
• mokřady MeSH
• ptáci parazitologie   MeSH
• stadia vývoje MeSH
• Trematoda klasifikace   izolace a purifikace   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Evropa MeSH

Interspecific relationships frequently determine the effect a pollutant can have on an organism, and this is especially true in closely interacting species such as hosts and parasites. The high spatial and temporal variability of contaminant concentrations combined with the movement of aquatic biota can further influence the consequences that are associated with contamination. We used a full factorial design for the exposed and unexposed partners of the relationship between the parasitic larvae (glochidia) of the European freshwater mussel (Anodonta anatina) and its host fish (Squalius cephalus) to identify the sources of variation in the sublethal endpoints of species interaction (the intensity of parasite attachment, the spatial position of glochidia on the host body, and encapsulation success). We used the water-borne human pharmaceutical compounds methamphetamine (a central nervous system stimulant) and tramadol (an opioid) at environmentally relevant concentrations (˜ 6.7 and 3.8 nmol L-1 of methamphetamine and tramadol, respectively) as a proxy for contaminant exposure because these compounds are emerging aquatic stressors that are known for high spatial and temporal variability in their detected concentration levels. The relationship between the bivalve and the fish species was influenced by the preceding contact with both methamphetamine and tramadol, but this effect was highly asymmetric. Our experimental design enabled us to identify the specific changes in the relationship outcome that are elicited by the exposure of individual partners, such as the significant increase in glochidia infection success rate from 59.6 ± 3.9% to 78.7 ± 2.8% (means ± s.e.) that was associated with host exposure to methamphetamine. Additionally, the significant interaction effect of the exposure was demonstrated by the lowered proportion of glochidia attached to gills after the coexposure of both partners to tramadol. The impact of pharmaceuticals on wild aquatic host-parasite relationships provides an example of the risks that are associated with the unintentional discharge of biologically active compounds into freshwater habitats. Given the increasing evidence showing the ecological impact of waste pharmaceuticals, the use of multitrophic interaction endpoints after joint and unilateral exposures provides an important step towards the realistic risk assessment of these compounds.

• Klíčová slova
• Fish, Freshwater mussels, Glochidia, Interspecific relationships, Methamphetamine, Tramadol,
• MeSH
• Anodonta účinky léků   růst a vývoj   MeSH
• chemické látky znečišťující vodu toxicita   MeSH
• Cyprinidae parazitologie   MeSH
• interakce hostitele a parazita účinky léků   MeSH
• larva růst a vývoj   MeSH
• monitorování životního prostředí metody   MeSH
• sladká voda chemie   MeSH
• testy toxicity MeSH
• žábry parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH

Parasite community composition of European bitterling (Rhodeus amarus), the only bitterling species occurring on the European continent, was investigated in 16 different localities from four European sea drainages during 1998-2007. A total of 41 species of metazoan parasites was identified. Nine parasite species are new records for European bitterling, namely Dactylogyrus rarissimus, D. suecicus, D. yinwenyingae, Gyrodactylus vimbi, Sphaerostomum globiporum, Petasiger sp., Paryphostomum radiatum, Ichthyocotylurus variegatus and Posthodiplostomum brevicaudatum. The specialist Gyrodactylus rhodei was the most widely distributed and one of the most prevalent species. The most frequent digenean species, represented by larval stages, was Metorchis xanthosomus. The parasite community of European bitterling was characterised by the dominance of generalists and parasites with autogenic life cycles. The rare occurrence of strictly endoparasitic species reflected the specific diet of the fish host. The character of the habitat significantly affected the parasite assemblages of bitterling. The greatest similarity was associated with lentic habitats (gravel pits and oxbows) and the lowest similarity between gravel pits and rivers. Juvenile bitterling from 8mm in length upwards were colonised by metazoan parasites, firstly by the monogenean G. rhodei. Host body size was positively correlated with parasite species richness, but the variability explained by length was low.

• MeSH
• Cyprinidae parazitologie   MeSH
• ekosystém * MeSH
• interakce hostitele a parazita * MeSH
• nemoci ryb parazitologie   MeSH
• parazitární nemoci u zvířat parazitologie   MeSH
• paraziti klasifikace   izolace a purifikace   fyziologie   MeSH
• velikost těla MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH

Heterosporous (polymorphic) microsporidia in mosquitoes are characterized by intricate life cycles involving multiple spore types responsible for horizontal (per os) and vertical (transovarial) transmission. They affect two generations of the mosquito and some involve an obligate intermediate host. Heterosporous microsporidia are generally very host and tissue specific with complex developmental sequences comprised of unique stages and events. Full details on the intricate relationships between heterosporous microsporidia and their mosquito hosts have only recently been elucidated. Edhazardia aedis (Kudo, 1930) and Culicospora magna (Kudo, 1920) have developmental sequences in larvae that involve gametogony followed by plasmogamy and nuclear association to form diplokarya. These diplokaryotic stages then undergo karyogamy and form binucleate spores responsible for transovarial transmission. In the filial generation, haplosis occurs as a result of nuclear dissociation to produce uninucleate spores infectious to larval mosquitoes. Amblyospora californica (Kellen et Lipa, 1960) has similar sequences except that haplosis is by meiosis to produce spores infectious for a copepod intermediate host. A third spore type is formed in the intermediate host responsible for infection in a new generation of the mosquito host.

• MeSH
• Culicidae parazitologie   MeSH
• elektronová mikroskopie MeSH
• interakce hostitele a parazita MeSH
• Microsporida růst a vývoj   fyziologie   ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Seven new species of Dactylogyrus Diesing, 1850 (Dactylogyridae) are described from the gills of seven endemic species of cyprinoids (Cyprinidae, Leuciscidae) inhabiting the Balkan Peninsula: Dactylogyrus romuli n. sp. from Luciobarbus albanicus (Greece), Dactylogyrus remi n. sp. from Luciobarbus graecus (Greece), Dactylogyrus recisus n. sp. from Pachychilon macedonicum (Greece), Dactylogyrus octopus n. sp. from Tropidophoxinellus spartiaticus (Greece), Dactylogyrus vukicae n. sp. from Delminichthys adspersus (Bosnia and Herzegovina), Dactylogyrus leptus n. sp. from Chondrostoma knerii (Bosnia and Herzegovina), and Dactylogyrus sandai n. sp. from Telestes karsticus (Croatia). To delineate species boundaries, we used an integrative taxonomic approach combining morphological and genetic data. With these tools, we illustrate that some species of monogeneans considered as cryptic might be designated as pseudocryptic (morphologically similar, not easily differentiated) after a posteriori detailed morphological examination, as happened with D. romuli n. sp. and D. remi n. sp. Thus, for accurate species characterization, it is particularly important to acquire both morphological and molecular data from the same individual specimens, ideally along with illustrations of taxonomically important structures directly taken from hologenophores. Using phylogenetic reconstruction, we investigated the phylogenetic position of newly described Dactylogyrus species within Dactylogyrus species from Balkan cyprinoids with regard to morphological characteristics, host range, and geographical distribution.

TITLE: Découverte de la diversité des Monogènes (Plathelminthes) des poissons cypriniformes endémiques de la péninsule balkanique : nouvelles espèces de Dactylogyrus et commentaires sur leur phylogénie et les associations hôte-parasite dans un contexte biogéographique. ABSTRACT: Sept nouvelles espèces de Dactylogyrus Diesing, 1850 (Dactylogyridae) sont décrites à partir des branchies de sept espèces endémiques de cyprinoïdés (Cyprinidae, Leuciscidae) habitant la péninsule balkanique : Dactylogyrus romuli n. sp. de Luciobarbus albanicus (Grèce), Dactylogyrus remi n. sp. de Luciobarbus graecus (Grèce), Dactylogyrus recisus n. sp. de Pachychilon macedonicum (Grèce), Dactylogyrus octopus n. sp. de Tropidophoxinellus spartiaticus (Grèce), Dactylogyrus vukicae n. sp. de Delminichthys adspersus (Bosnie-Herzégovine), Dactylogyrus leptus n. sp. de Chondrostoma knerii (Bosnie-Herzégovine) et Dactylogyrus sandai n. sp. de Telestes karsticus (Croatie). Pour la délimitation des espèces, nous avons utilisé une approche taxonomique intégrative combinant des données morphologiques et génétiques. Avec ces outils, nous illustrons que certaines espèces de Monogènes considérées comme cryptiques pourraient être désignées comme pseudocryptiques (morphologiquement similaires, pas facilement différenciées) après un examen morphologique détaillé a posteriori, comme cela s’est produit avec D. romuli n. sp. et D. remi n. sp. Ainsi, pour une caractérisation précise des espèces, il est particulièrement important d’acquérir des données morphologiques et moléculaires à partir des mêmes spécimens individuels, idéalement avec des illustrations de structures taxonomiquement importantes directement prises à partir d’hologénophores. En utilisant la reconstruction phylogénétique, nous avons étudié la position phylogénétique des espèces de Dactylogyrus nouvellement décrites au sein des espèces de Dactylogyrus des cyprinoïdés des Balkans en ce qui concerne les caractéristiques morphologiques, la gamme d’hôtes et la distribution géographique.

• Klíčová slova
• Balkan Peninsula, Cyprinidae, Dactylogyridae, Dactylogyrus, Leuciscidae, Monogenea,
• MeSH
• biodiverzita * MeSH
• druhová specificita MeSH
• fylogeneze * MeSH
• fylogeografie MeSH
• interakce hostitele a parazita * MeSH
• máloostní * parazitologie   MeSH
• paraziti * MeSH
• Trematoda * klasifikace   genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Balkánský poloostrov MeSH
• Chorvatsko epidemiologie   MeSH