Component Community Research Articles

Patterns of zeta diversity in ectoparasite communities harboured by small mammals at three hierarchical scales: taxon-invariance and scale-dependence.

We studied compositional turnover in communities of fleas and mites harboured by small mammals using zeta diversity metric (similarity between multiple communities) and asked whether the patterns of zeta diversity decline with an increase in the number of communities differ between taxa and hierarchical scales [infracommunities (parasite assemblages on individual hosts), component communities (parasite assemblages harboured by host populations), and compound communities (all parasite species in a locality)]. The average number of shared species declined with an increasing number of communities (zeta order). It attained zero at higher orders in infracommunities of both taxa with the shape of the zeta decline being best fitted by the negative exponential function, and the retention rate curves being modal. In contrast, zeta diversity values for compound communities of mites and fleas did not attain zero at higher zeta orders, and the form of the zeta decline was best fitted by the power-law function, whereas the retention rate curves were asymptotic. In component communities, the form of zeta decline was best fitted by either exponential or power-law function in dependence of whether communities were considered within a host across localities or across hosts within a locality and whether ubiquitous species were taken into account. Our main conclusions are that (a) the rules governing compositional turnover in parasite communities for the lowest and the highest hierarchical scales are taxon-invariant but scale-dependent and (b) species composition of infracommunities is mainly driven by stochastic assembly processed, whereas that of compound communities is mainly driven by niche-based processes.

Variation in Helminth Parasite Component Communities of Gambusia affinis.

In north-central Texas streams, seasonal changes in ambient temperature and rainfall result in dynamic variation in microhabitat structure, affecting the distribution and abundance of hosts. Since the complex life cycles of parasites require the presence and interaction of multiple hosts, the seasonal variations in microhabitats could influence parasite component communities within these ecosystems. Gambusia affinis (western mosquitofish) serves as a host for a variety of larval and adult parasites. Factors that affect helminth component communities in populations of mosquitofish from the Paluxy River were investigated in this study. Gambusia affinis individuals were collected from 3 sites monthly from June 2015 through August 2016. All helminth parasites were collected during necropsy and subsequently identified. From 495 mosquitofish, 5,283 helminths were collected. Component community diversity varied among collection sites and collection dates and was positively influenced by river flow. These results indicate that helminth assemblages infecting mosquitofish in the Paluxy River vary through time and space, as well as in response to environmental variation (i.e., changes in water flow).

Systemic collapse of a host-parasite trematode network associated with wetland birds in Europe.

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.

Diversity of helminth parasites of eight siluriform fishes from the Aguapeí River, upper Paraná basin, São Paulo state, Brazil.

Fishes of the order Siluriformes, known as catfishes, have a global distribution with more than 3,600 valid species of which 2,087 occur in the Neotropical region. Despite being highly diverse, abundant, and of economic importance as food and ornamental fishes, knowledge about the diversity and distribution of their helminth parasites is fragmentary and scarce. Eight species of catfishes (Pterodoras granulosus, Trachydoras paraguayensis, Pimelodella avanhandavae, Loricariichthys platymetopon, Pterygoplichthys ambrosettii, Rhinelepis aspera, Hemisorubim platyrhynchos, and Sorubim lima) from the Aguapeí River, Upper Paraná River basin, municipality of Castilho, São Paulo State, Brazil, were surveyed for helminth parasites.Collected fishes were weighed, measured, and examined for helminth parasites following standard methodology. Fifty helminth parasite taxa (23 monogeneans, 13 digeneans, 11 nematodes, and three cestodes) were found from a total of 405 fishes screened. The helminth taxon that showed the highest mean intensity of infection and mean abundance was the nematode Rondonia rondoni from P. granulosus, followed by the nematode Parasynodontisia petterae from R. aspera. The ecological analyses were carried out at the component community level and at the infracommunity level. Trachydoras paraguayensis had the richest helminth component community. Pterygoplichthys ambrosettii had the most diverse helminth component community and R. aspera had the lowest. Both hosts are loricariids and have similar diet. However, the high parasite diversity of P. ambrosettii is due to the number of dactylogyrids species found (10), which are directly transmitted, whereas only three dactylogyrid species were found in R. aspera. At infracommunity level, the nematode species R. rondoni and P. petterae dominated the parasite communities. This study presents 38 new host records, contributing considerably to increase the diffuse knowledge of helminth parasites of Neotropical siluriforms.

Interannual variation in the metazoan parasite communities of bigeye trevally Caranx sexfasciatus (Pisces, Carangidae).

Parasite communities in Caranx sexfasciatus were characterized and analyzed to determine any interannual variations in structure and/or species composition. In total, 422 C. sexfasciatus were collected from Acapulco Bay, Mexico, between May 2016 and March 2019. Thirty-two taxa of metazoan parasites were identified: five Monogenea, thirteen Digenea, one Acanthocephala, one Cestoda, three Nematoda, seven Copepoda, and two Isopoda. Monogeneans were the most frequent and abundant parasite species in all sampling years. Parasite species richness at the component community level varied significantly from 8 (May 2016) to 25 (March 2019) and was similar to previous reports for other species of Carangidae. The component communities and infracommunities in C. sexfasciatus were characterized by low parasite species numbers, low diversity, and dominance of a single species (the monogenean Neomicrocotyle pacifica). Parasite community structure and species composition varied between sampling years and climatic seasons. Seasonal or local fluctuations in some biotic and abiotic environmental factors probably explain these variations.

First study on the helminth community structure of the neotropical marsupial Metachirus myosuros (Didelphimorphia, Didelphidae).

Metachirus myosuros is a marsupial species widely distributed in South America. Despite this, there is a lack of knowledge about its helminth parasites and helminth community structure. The aims of this study were to describe the species composition and determine the parasitological parameters of helminth communities of M. myosuros in preserved areas of the Atlantic Forest, Igrapiúna, Bahia state, northeastern Brazil. Parasites were searched from 19 specimens of this marsupial (18 were infected with at least one species), counted and identified. Ten species of helminth parasites were obtained: 7 nematodes, 2 platyhelminths and 1 acanthocephalan. The most abundant species were Aspidodera raillieti, Cruzia tentaculata, Physaloptera mirandai and Viannaia conspicua (Nematoda). These species were also the only dominant ones in the component community. Male hosts had higher prevalence of P. mirandai and greater abundance of V. conspicua. We observed a relationship between host body size and helminth abundance in both male and female hosts, and between host body size and helminth species richness in female hosts. This was the first study to analyze the helminth fauna and helminth community structure of M. myosuros. This was the first report of occurrences of A. raillieti and Didelphonema longispiculata in M. myosuros.

Metazoan parasites of Plagioscion squamosissimus (Osteichthyes: Sciaenidae) of two rivers from the eastern Amazon (Brazil).

Plagioscion squamosissimus, commonly known as "white hake" or "corvina", is among the most commercially important fish in the Amazon and host to a great diversity of endoparasites. The aim of the present study was to compare the communities and infracommunities of metazoan parasites that infect P. squamosissimus in two rivers from the eastern Brazilian Amazon. A total of 75 specimens of P. squamosissimus were collected from Lago Grande do Curuái and the mouth of the Tapajós River. Morphological analysis revealed the presence of 16 parasite species, three myxozoans (Myxobolus sp., Ceratomyxa sp., Henneguya sp.), two trematodes (Austrodiplostomum compactum, Digenea gen. sp. (metacercariae), two monogeneans (Diplectanum sp., Euryhaliotrema sp.), three nematodes (Procamallanus (S.) sp., Anisakis sp., Pseudoproleptus sp. (larva), two acanthocephalans (Rhadinorhynchus plagioscionis and Neoechinorhynchus sp.), one Cestoda Ptychobothriidae gen. sp. and three crustaceans (Therodamas sp., Ergasilus sp., Dolops sp.). Six new records of parasites of P. squamosissimus were made, of which three were myxozoan species, one nematode species and two crustacean species. There were differences in the component communities of parasites of both rivers studied and these were discussed.

Fossil fern rhizomes as a model system for exploring epiphyte community structure across geologic time: evidence from Patagonia.

BackgroundIn extant ecosystems, complex networks of ecological interactions between organisms can be readily studied. In contrast, understanding of such interactions in ecosystems of the geologic past is incomplete. Specifically, in past terrestrial ecosystems we know comparatively little about plant biotic interactions besides saprotrophy, herbivory, mycorrhizal associations, and oviposition. Due to taphonomic biases, epiphyte communities are particularly rare in the plant-fossil record, despite their prominence in modern ecosystems. Accordingly, little is known about how terrestrial epiphyte communities have changed across geologic time. Here, we describe a tiny in situ fossil epiphyte community that sheds light on plant-animal and plant-plant interactions more than 50 million years ago.MethodsA single silicified Todea (Osmundaceae) rhizome from a new locality of the early Eocene (ca. 52 Ma) Tufolitas Laguna del Hunco (Patagonia, Argentina) was studied in serial thin sections using light microscopy. The community of organisms colonizing the tissues of the rhizome was characterized by identifying the organisms and mapping and quantifying their distribution. A 200 × 200 µm grid was superimposed onto the rhizome cross section, and the colonizers present at each node of the grid were tallied.ResultsPreserved in situ, this community offers a rare window onto aspects of ancient ecosystems usually lost to time and taphonomic processes. The community is surprisingly diverse and includes the first fossilized leafy liverworts in South America, also marking the only fossil record of leafy bryophyte epiphytes outside of amber deposits; as well as several types of fungal hyphae and spores; microsclerotia with possible affinities in several ascomycete families; and evidence for oribatid mites.DiscussionThe community associated with the Patagonian rhizome enriches our understanding of terrestrial epiphyte communities in the distant past and adds to a growing body of literature on osmundaceous rhizomes as important hosts for component communities in ancient ecosystems, just as they are today. Because osmundaceous rhizomes represent an ecological niche that has remained virtually unchanged over time and space and are abundant in the fossil record, they provide a paleoecological model system that could be used to explore epiphyte community structure through time.

Temporal and seasonal variations in parasites of Metynnis lippincottianus (Characiformes: Characidae), a host from the eastern Amazon (Brazil)

ABSTRACTThis study investigated the influence of temporal and seasonal variation (rainy/dry cycle) on the component community structure and infracommunities of parasites in Metynnis lippincottianus from the eastern Amazon (Brazil). A total of 8,774 parasites representing 9 species and 22,765 parasites representing 12 species was collected in 2011 and 2016 respectively, but only 42.8% of the species were common to both study years. In both years, there was a dominance of Ichthyophthirius multifiliis and the component community was 51% dissimilar. The species richness of parasites and the Berger–Parker dominance were higher in 2016, while the evenness and Brillouin diversity were higher in 2011. The prevalence and abundance of I. multifiliis and P. pillulare, as well as the prevalence of Contracaecum sp. were higher in the rainy season. The abundance of Anacanthorus strongylophalus, Urocleidoides sp., Dadayus pacupeva and Dadaytrema oxycephala was higher in the dry season. Infection with Procamallanus (Spirocamallanus) inopinatus was not influenced by the season, while by Trichodina sp. occurred only in the dry season and Ergasilus xinguensis only in the rainy season. The species richness of parasites, Brillouin diversity index and evenness were higher in the dry season, while the Berger–Parker index was higher in the rainy season. Temporal variation of communities and infracommunities of parasites was influenced by the body size of host populations and increase in anthropogenic impacts. Effect of seasons on environmental quality, host size and availability of infective stages of parasites were the determining factors in structuring the component communities and infracommunities of parasites.

How epidemiological patterns shift across populations in an exotic lizard.

Several factors influence the dynamics and structure of parasite communities. Our goal was to investigate how the community composition, prevalence and abundance of parasites change across seven populations of the exotic lizard Hemidactylus mabouia in Northeast Brazil, and to describe ontogenetic and sex variations. We found differences in the composition of component communities and patterns of infection according to the host body size across the lizard populations. We did not find any variation between the sexes regarding epidemiological patterns, which can probably be explained by the similar diet and habitat use of male and female H. mabouia. An unusually high abundance and prevalence of trematodes infecting this host lizard was apparent when we compared other native lizard hosts, and we suggest that local environmental conditions might be advantageous to the development and life cycle of these parasites due to the abundance of all the intermediate and definitive hosts.

Parasites as indicators of fish population structure at two different geographical scales in contrasting coastal environments of the south-western Atlantic

Fish parasites are widely used as biological tags of stocks and populations of their hosts at large spatial scales, but less frequently at small geographical scales. The application of this methodology at small scales requires heterogeneity in the availability of infective stages of parasites and hosts with high site fidelity. Here we tested the value of parasite tags at both large and small spatial scales using the Argentine silverside, Odontesthes argentinensis (Valenciennes, 1835) as a model. This is a marine fish that can tolerate a wide range of salinities and has great phenotypic plasticity, which has promoted adaptive divergences at reduced spatial scales across populations, in the absence of geographical barriers isolating them, which could be reflected in their parasite assemblages. A total of 142 specimens were examined for parasites. Samples were collected at two close localities from each of two different biogeographical regions of the south-western Atlantic. The structure and composition of both parasite infracommunities and component communities were analysed through uni and multivariate statistics. All sites were significantly different in their infracommunity structure, even those that were at shorter distances from each other. However, infracommunity composition and component community structure showed higher similarities within each region than between samples from different ones. These results proved that fish parasites are valuable tools to assess fine-scale population structure of their hosts when site fidelity and adaptations to local conditions prevail. The inclusion of parasite indicators as complementary tools in such kind of studies can provide valuable evidence for those resources requiring stock assessments and management at fine-scale, in order to prevent negative impacts over exploited populations.

Species associations and trait dissimilarity in communities of ectoparasitic arthropods harboured by small mammals at three hierarchical scales

1. This study tested the relationships between the probability of pairwise species co‐occurrence and pairwise dissimilarity in their traits in infracommunities (across assemblages harboured by conspecific individual hosts within a locality), component communities (across assemblages harboured by host species within a locality), and compound communities (across assemblages in different localities) of fleas and gamasid mites parasitic on small mammals in Western Siberia.2. A significant, albeit weak, tendency was found for flea communities harboured by conspecific host individuals, host species, and host communities to be composed of similar species. No relationship between the probability of co‐occurrence and trait dissimilarity was detected for mite communities at any hierarchical scale.3. For fleas, this study explained the link between positive co‐occurrence and trait dissimilarity by a process resembling environmental filtering realised mainly via host traits for infracommunities and component communities and via off‐host environment for compound communities, thus suggesting that the identical shape of the relationships between co‐occurrence and trait dissimilarity at different scales was driven by different mechanisms.4. The explanation of the lack of this relationship in mites included: (i) the paucity of the subset of mite traits used in this study and its potential inadequacy for the question at hand; and (ii) possible masking of the effect induced by one trait on co‐occurrence owing to the lack of this effect induced by another trait(s).5. Caution is recommended regarding the compilation of a dataset involving multiple traits, its analysis, and the interpretation of the results.

Сезонная динамика паразитофауны и структуры компонентного сообщества паразитов хариуса <i>Thymallus thymallus</i> (Linnaeus, 1758) из реки Луженьги (бассейн реки Северной Двины)

Развитие учения о паразитарных сообществах позволило оценивать нарушения структуры гидробиоценозов и популяций рыб. Сбор материала произведен с мая по сентябрь 2011 – 2013 гг. из р. Луженьга (Вологодская область). Исследовали 150 экз. хариуса по 10 выборок (61 самка, 89 самцов) по 15 экз. в каждой. Компонентное сообщество паразитов хариуса с мая по сентябрь последовательно проходит 3 стадии развития, обусловленные сменой генераций составляющих его видов. Это формирующееся сообщество в мае — начале июня, сформированное во 2-й и 3-й декадах июня, разрушающееся в июле–начале сентября и вновь формирующееся. У хариуса выявлены 16 видов паразитов. Их число колебалось от 9 в начале июня и до 13 в октябре. У рыбы на протяжении всего периода исследований присутствовали 6 видов паразитов. От мая к началу июня число особей инвадентов и их биомасса упали в 2 раза, к концу июня значения этих показателей выросли в 2,3 раза с последующим резким падением в июле числа особей в 3,7 – 3,8 раза, биомассы — в 1,8 – 2,7 раза. Далее к октябрю идёт плавный рост значений этих показателей. С мая по октябрь в сообществе паразитов лидируют автогенные виды и виды-специалисты.

Factors linked to interannual variation in the metazoan parasite communities of black skipjack, Euthynnus lineatus (Pisces: Scombridae)

AbstractMarine parasite communities can exhibit temporal and spatial changes in response to seasonal and local variations in several biotic and abiotic environmental factors. Limited attention has been given to the influence of abiotic factors, so their effects on parasite community structure remain unclear. A total of 496 specimens of Euthynnus lineatus were collected over a 7‐year period (2012–2018) from Acapulco Bay, Mexico. Their parasite communities were analyzed to determine if they experience interannual variations due to local biotic and abiotic factors. Thirty‐three metazoan parasite species were recovered and identified: four species of Monogenea (adults); 16 of Digenea (one larvae and 15 adults); two of Acanthocephala (adults); two of Cestoda (larvae); three of Nematoda (two larvae and one adult); and six of Crustacea (three Copepoda, and three Isopoda). Species richness was greatest among the digeneans, which represented 48% of the total species recovered, followed by the crustaceans (19% of total species). Species richness at the component community level (14–24 species) was similar to reported richness in other small tuna species. The component communities and infracommunities of E. lineatus exhibited a similar pattern: high species richness and diversity, and numerical dominance by a single species, mainly by one of the didymozoids Allopseudocolocyntotrema claviforme or Pseudocolocyntotrema yaito. Parasite community structure and species composition varied among sampling years. Variations were possibly caused by a combination of abiotic and biotic factors which generated notable changes in the infection levels of several component species during the study period. These communities may therefore be unpredictable in terms of structure and species composition, as has been suggested for other communities of marine parasites.

Helminth Community Structure of the Gray Four-Eyed Opossum Philander opossum (Mammalia: Didelphidae) in the Neotropical Portion of Mexico

Studies on helminth communities associated with didelphids are scarce; the majority of works have focused at taxonomic level. To increase the ecological knowledge of these host-parasite associations, during March (dry season) of 3 consecutive years (2013-2015) a total of 49 adults of the gray four-eyed opossum (Philander opossum) was collected in the Neotropical portion of Mexico (Agua Fría, Chiapas State) and examined for helminths. The main objectives of this study were to describe the infra- and component communities of helminths associated with P. opossum and to compare the helminth fauna of the Mexican population of this host species with those studied in French Guiana and in other Mexican terrestrial didelphids. The helminthological record of this host consisted of 12 species: 7 taxa of Nematoda, 3 of Trematoda, 1 Cestoda, and 1 Acanthocephala. Eight of the 12 taxa have been previously recorded in Didelphidae and 4 represent accidental infections ( Glossocercus sp., Stomylotrema vicarium, Spirura mexicana and Acanthocephala gen. sp.). Diet of hosts is the main structuring factor of the communities (92% of the helminth species were recruited through ingestion). Forty-eight hosts were parasitized by at least 1 helminth species; Rhopalias coronatus was the most prevalent and abundant species in the hosts sampled. No significant differences were found in global prevalence among the helminth species present in all samplings, considering host sex and year. The dominance exerted by R. coronatus led to low values of evenness and diversity at both community levels. No significant differences were observed in composition of helminth species among the 3 sampling years regarding sex. The results of our study showed changes in helminth abundance at infracommunity level; during the first sampling these changes are explained by species with direct life cycle ( Viannaia sp. and Cruzia tentaculata), whereas in last 2 surveys the explanation can be attributed to species with heteroxenous life cycles (particularly R. coronatus, Duboisiella proloba, and Turgida turgida). Thirty-three percent of the helminth species recorded in P. opossum in Agua Fría is shared with the other 2 terrestrial species of didelphids sampled in different sites of Mexico: Didelphis marsupialis and Didelphis virginiana. In contrast, samples from French Guiana and Agua Fría, differ in terms of helminth fauna, confirming that the helminth communities of opossum species inhabiting the same locality show higher levels of taxonomic similarity than communities of conspecific marsupials allopatrically distributed.

Species composition and structure of parasites component communities of tugun <i>Coregonus tugun</i> (Pallas, 1814) from the Khatanga and Yenisei Rivers

Tugun Coregonus tugun (Pallas, 1814) is an endemic of Siberia. Information about the species composition and structure of tugun parasite community on the stage of spawning migration is described in this paper. We carried out ichtioparasitologic studies in the Yenisey and the Khatanga Rivers in 20112014. Tugun parasite complex from the Khatanga River remains statistically identical in species composition, number of individuals and biomass and differs from those of the Yeniseis tugun over the entire study period. Apparently two different stocks of tugun were investigated in the Yenisei River. One of them lives in the Yeniseis streambed, the other one lives in the Podkamennaya Tunguska River. The composition of the parasitic fauna of tugun from two rivers is formed by generalist species. Tugun parasites component communities from all material collection stations have high values of the Shannon index and two dominant species (by numbers of parasites and by biomass). We found out that the species biomasses differ significantly on the graphic community structure. The description of tugun parasite communities corresponds to characteristic of a climax community on the stage of destruction except the graphic structure. In the analyzed parasitic communities the processes of egg laying and larval appearance, the death of parasites of previous year generation and infection with this year parasites occur simultaneously. The stages of formation and destruction of the community overlap. The described state of tugun parasites communities has an adaptive value. The load on the host body is reduced which ensures the long-term existence of parasites.

PENDIDIKAN KARAKTER DALAM MEMBENTUK PERILAKU SUSILA ANAK SEKOLAH DASAR

<p><em>Indonesian life corresponding 1945 aspired not yet achieved its full potential . Various cases ranging from sexual abuse , crime , corruption, human trafficking , peraktik prostitution , looting , promiscuity , rampant levels of violence children and adolescents , crimes against friend , theft teens , the habit of cheating , drug abuse , pornography , and environmental destruction , until the murder has not been solved by the security forces and the Indonesian government . Efforts could be done to overcome this phenomenon is the way to improve the character of each individual through character education should start at an early age formed . In elementary school character education can be transformed through learning in the classroom and through extracurricular activities and cooperation between education centers tri component ( family , school and community ) are expected cultivation of character education can be implemented optimally.</em></p>

Helminth fauna in a semi-arid host species - scaled quail (Callipepla squamata)

Helminths were examined from 145 scaled quail (Callipepla squamata) collected during the 2012-2013, 2013-2014 and 2014-2015 hunting seasons from a semi-arid region of Texas that spans four ecoregions. Helminth infracommunities were species poor, averaging 1.7 (range 1-4) species. Six species occurred within the component community of which one (Oxyspirura petrowi) is known to be pathogenic to quail. Aulonocephalus pennula was most abundant (9991 individuals, 95% of total) followed by O. petrowi (391 individuals, 4%). Each of the remaining four species was rare (≤21% prevalence) and contributed few individuals (<1%). In the High Plains ecoregion, prevalence of O. petrowi was higher in host collections made during the 2013-2014 hunting season than either hunting seasons 2012-2013 or 2014-2015 and was higher in the High Plains ecoregion than the Edwards Plateau ecoregion during the 2013-2014 hunting season. Mean abundance of A. pennula and O. petrowi was higher in scaled quail from the High Plains ecoregion than the Edwards Plateau ecoregion. Our results provide new information about helminth fauna in scaled quail, persistence of indirect lifecycle helminth species within a semi-arid region, and the occurrence of pathogenic helminth species within this host species.

Metazoan parasites of Calophysus macropterus (Siluriformes: Pimelodidae) in the Acre and Iaco rivers in the western Amazon region of Brazil: diversity, similarity and seasonal variation

ABSTRACTThe diversity, similarity and seasonal variation of metazoan parasite communities in Calophysus macropterus in the Acre and Iaco rivers, in the western Amazon (Brazil), was investigated. Parasites from 13 taxa were collected from C. macropterus in both rivers: four species of monogeneans, four nematodes, two cestodes, one digenean, one crustacean and one pentastomid. In hosts from the Acre river, Cucullanus pinnai predominated; while in hosts in the Iaco river, Monticellia amazonica predominated. The component communities of the parasites among the hosts in the two rivers presented high similarity (100%). Prevalence of Alinema amazonicum was higher in hosts in the Acre river; while the prevalence of C. pinnai was higher in hosts in the Iaco river and the mean prevalence and abundance of M. amazonica were higher in fish from the Iaco river. Regarding C. macropterus from the Acre river, infection levels by A. amazonicum were higher during the rainy season, while Demidospermus pinirampi only occurred in the dry season and Procamallanus (Spirocamallanus) inopinatus only occurred in the rainy season. In hosts from the Iaco river, infections by larvae of Anisakidae gen. sp. were higher during the dry season, while infection by Rudolphiella piracatinga and Sebekia sp. only occurred in the rainy season. However, P. (S.) inopinatus, Ergasilus callophysus, Ameloblastella unapi, Demidospermus luckyi, Demidospermus macropteri and D. pinirampi only occurred in the dry season. High similarity of the component communities of the parasite was observed between the rainy and dry seasons. These results suggest that factors other than location and seasonality were influencing the communities and infracommunities of the parasites found. Lastly, C. macropterus is a new host for almost 50% of the parasite species found. In addition, the results from the present study have expanded the geographical range of these 13 species of parasites to the western Amazon region.

Unconventional support for a raptorial niche division between Australaves and Afroaves: The distribution of helminths

Deep evolutionary relationships within raptorial niche have recently been challenged. Little is known as to whether birds of the raptorial niche share congruent or host-switching communities of parasites. Here, we analyzed the helminth component communities associated with birds of prey and owls. From 1962 to 2015, we examined 1731 birds of prey and owls in Czechia, and we provide a meta-analysis based on the available literature. Both the analysis of newly examined birds as well as the meta-analysis of previous studies suggested low similarities in the helminth component communities in Strigiformes relative to those in Accipitriformes (Sørensen similarity indices 0.380 in Czechia and 0.324 worldwide) or Falconiformes (0.341 and 0.328), as well as low similarities in the helminth component communities in Falconiformes to those in Accipitriformes (0.366 and 0.413). Globally, 59.6% of helminth species found in Accipitriformes, 39.5% of those in Falconiformes and 38.3% of those in Strigiformes were obligate specialists that were limited to a single examined bird order. Another 11.5%, 12.8% and 8.3% of species had core hosts in only a single order. Only five helminth species infected all three bird orders at a similar prevalence. The differences in prevalence cannot be explained by differences in food composition. We provide detailed information on the prevalence, seasonality, age- and sex-specificity, intensity and lethality of helminth infections. In conclusion, we provide the first systematically collected evidence on the congruence of the helminth distribution and phylogeny of the raptorial niche, which is consistent with its split into Australaves and Afroaves.