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In this study is made an ecological analysis of the species composition, structure of the helminth community and the invasion degree of Bufo bufo in different habitats in the National Park «Smolny» (Republic of Mordovia, Russia). In 2018–2019, they were collected in five biotopes with different spawning water bodies. Nine helminth species were found, including five Trematoda species and four Chromadorea (Nematoda) species. There are two groups of species. The first of them develops on terrestrial nematodes Rhabdias bufonis, Oswaldocruzia filiformis, Oxysomatium brevicaudatum, rather common, regardless of the habitat, with a high degree of invasion and dominating in the helminth community. The species of the second group develop in aquatic nematode Cosmocerca ornata, as well as trematodes which are rarer, locally and with a low infection rate. They are typical parasites of green frogs (genus Pelophylax). The diversity of helminthes and the structure of their component community depend on the type, nature of the spawning water body and the presence of green frogs. Individuals of B. bufo, spawning in stagnant water bodies where green frogs live, have a more diverse helminth species composition, because there are helminths of the second group, whose development is related to the aquatic environment. The structure of their community is more complex. Bufo bufo, when using flowing water bodies without green frogs for spawning, has a depleted helminth composition and a simplified structure of their community. The obtained results have demonstrated the influence of one allotopic amphibian species on the formation of helminth community of another species under conditions of temporary syntopic occurrence.

Simple Summary The Lusitanian pine vole is an endemic rodent of the Iberian Peninsula, which has a burrowing behaviour and prefers to live underground. It feeds on bark and roots causing severe damage to trees. In Asturias (NW Spain), this species is considered a pest causing economic losses in apple orchards, damaging the tree, and sometimes even causing its death. With the aim to shed light on the helminth community of this rodent pest species and to elucidate which intrinsic and extrinsic factors affect its helminth species, a faunistic-ecological study was carried out. For this purpose, our own collection of 710 voles from several orchards of various locations in Asturias was used. The results of the ecological study revealed the influence of climate variables, the year and season of capture, as well as the host age, on the diversity of the helminth community and the infection parameters of helminth species, underlining the importance of their life cycles. Our findings on the helminth community of the Lusitanian pine vole in Asturias could be used to improve the biological methods applied to control the population of this rodent pest. Abstract The Lusitanian pine vole, Microtus lusitanicus, an endemic fossorial rodent of the Iberian Peninsula, has a burrowing behaviour and prefers to live underground. It feeds on bark and roots causing severe damage to trees. In Asturias (NW Spain), where M. lusitanicus is considered a pest in several orchards, a faunistic-ecological study was carried out to describe the helminth community of this species and the main factors that could influence its helminth component species. For this purpose, our own collection of 710 voles from several orchards of various locations in Asturias was used. Eight helminth species, four cestodes and four nematodes, were found. Statistical non-parametric tests were used to analyse the effects of extrinsic and intrinsic factors on the diversity of the helminth community and species prevalence and abundance. The results show the influence of climate variables, the year and season of capture, as well as host age, on the diversity of the helminth community and the infection parameters of some helminth species, underlining the importance of their life cycles. In addition to shedding light on the helminth community of this rodent in Asturias, the results obtained could be used to improve the biological methods applied to fight the M. lusitanicus pest.

Suncus etruscus is the smallest living mammal on Earth by mass. Most adults weigh 1.8–3 g with a body length of 35–48 mm. Catching it in small mammal traps in nature is extremely difficult due to its minute size, and therefore special trapping methods must be used. We had the unique opportunity of studying, for the first time, the helminth parasites of 166 individuals of S. etruscus, part of the largest collection in the world, which belonged to the French scientist Dr Roger Fons (1942–2016). A total of 150 individuals were captured in the Banyuls-Cerbère area (France) and 16 in the island of Corsica (France). We found seven helminth species, specifically, the cestodes Joyeuxiella pasqualei larvae, Mesocestoides sp. larvae, Staphylocystis claudevaucheri, S. banyulsensis, S. cerberensis, and Pseudhymenolepis sp., and the nematodes Aonchotheca sp. and Nematoda gen. sp. larvae. Neither trematodes nor acanthocephalans were detected. We provide prevalences, infracommunity compositions, and helminth associations. The adult helminth community of S. etruscus seems to be highly specific, i.e., oioxenous, and linked to its insectivore diet. Due to its small size, S. etruscus has undergone numerous physiological adaptations that have probably influenced its helminth spectrum as well as its helminth specificity.

The growing human population and the development of urban areas have led to fragmentation and destruction of many natural habitats but have also created new urban habitats. These environmental changes have had a negative impact on many species of plants and animals, including parasite communities. The aim of present study was to compare the helminth communities of Apodemus flavicollis and Apodemus agrarius in natural and urban habitats. Helminth burdens were assessed in 124 mice, 48 A. flavicollis, and 76 A. agrarius from two managed forests close to the city boundaries and two city parks within Warsaw, Central Poland. In total, eight species of helminths, Nematoda (n = 3), Digenea (n = 2), and Cestoda (n = 3), were identified. Helminth community structure and prevalence/abundance of individual helminth species differed significantly between the two Apodemus species. Overall, prevalence and abundance of helminth species were significantly higher in A. agrarius compared to A. flavicollis. For A. flavicollis, higher prevalence and abundance of helminths were detected in individuals from managed forest habitats in comparison to city parks. In striped field mice, much higher prevalence and mean abundance were recorded in rodents trapped in city parks than in managed forests. This phenomenon may be explained by better adaptation of A. agrarius, compared to A. flavicollis, to city habitats, resulting in high local densities of mice and the full range of parasite species affecting this host species. Our data confirm also that the established routes of infection exist for selected helminth species in the urban environment.

Summary Information about the prevalence of helminth parasites of the yellow-necked mouse, Apodemus flavicollis, in the Iberian Peninsula is almost non-existent and there is no reliable data reported from Spain. Fourteen A. flavicollis from the Erro River valley (Navarre, Spain) were examined for endoparasites, between February 2001 and July 2002. Thirteen specimens (92.9 %) of the total sample were parasitized by at least one of the following six helminth species: one trematode (Corrigia vitta), one cestode (Taenia parva larvae) and four nematodes (Trichuris muris, Calodium hepaticum, Heligmosomoides polygyrus and Syphacia stroma). This is the first report about the helminthfauna of A. flavicollis in the Iberian Peninsula. Nevertheless, a larger number of hosts should be analysed to complete these preliminary results and to adequately characterize the helminth community of this rodent. The finding of C. hepaticum, the causative agent of human capillarosis, stands out.

Anthropogenic ecosystem modification has affected over 80% of the global land cover. Interest in its effects on wildlife has been growing over the past several decades, specifically in regard to biodiversity and ecosystem function. Parasites are of particular interest, because they directly impact animal health, and can be transmitted to humans through the process of zoonosis. However, most studies so far tended to focus on only one or two parasites with few looking at the entire community, thereby limiting our understanding of the effects of ecosystem modification on parasitic organisms. In this study, we estimated the intestinal helminth diversity and species richness of the large Japanese field mouse (Apodemus speciosus), as well as the prevalence and abundance of each species in two modified ecosystems, a rural agricultural area and an urban park. We then compared them to a natural area to see how they have been altered. We found that diversity, prevalence, and abundance were all highly altered within both modified ecosystems, but generally to a greater degree within the urban park. However, there was great variation in the direction and degree of response of each helminth species, suggesting that generalized trends may be difficult to ascertain. Furthermore, it is important to analyze the entire helminth community, because interspecific interactions and the effect that ecosystem modification has on them may help determine what species persist.

The helminth community of the Iberian hare, Lepus granatensis, in the southern Spanish province of Granada was analysed, thorough the study of 487 individuals shot by hunters between November 1998 and October 1999. Six helminth species were found: Mosgovoyia pectinata (Cestoda); Trichostrongylus retortaeformis, Nematodiroides zembrae, Nematodirus sp., Passalurus ambiguus and Micipsella numidica (Nematoda). N. zembrae and M. pectinata (62.4 % and 17.2 %, respectively) were the only component species found. The predominance of helminth species with a direct life cycle is noteworthy. These two component species were significantly influenced by season of capture. Other factors, such as host age and municipality of capture, influenced the prevalences and/or abundances of the component species, while host sex did not exert any important role. These variations, determined by extrinsic and/or intrinsic factors, in the helminth community could be related to the ecology of the Iberian hare, mainly diet, habitat and behaviour.

The helminth communities of silverside, Odontesthes bonariensis (Valenciennes, 1835), from two Argentinean lagoons were studied and compared at component community and infracommunity levels. Nine helminth species were found: five digeneans (Austrodiplostomum cf. mordax, Ascocotyle (Phagicola) cf. diminuta, Ascocotyle sp., Thometrema bonariensis and Saccocoelioides sp.); two nematodes (Contracaecum sp. and Hysterothylacium sp.); one acanthocephalan (Wolffhugelia matercula) and one cestode (Cangatiella macdonaghi). Odontesthes bonariensis is a new host record for five parasite species. Richness, diversity and number of helminths in silversides from Salada Grande lagoon were higher than in those from Lacombe lagoon. This could be related with lagoon size, abundance of mollusks and fish-eating birds, and size and diet of silversides captured in each lagoon. In Salada Grande lagoon the helminth community of silversides was dominated by the allogenic and generalist species A. cf. mordax; while the autogenic and intermediate specialist species C. macdonaghi was dominant in Lacombe lagoon. Host sex did not affect richness, diversity or total abundance, whereas host size was positively correlated with these attributes, except diversity in Salada Grande lagoon. Las comunidades de helmintos del pejerrey, Odontesthes bonariensis (Valenciennes, 1835), procedentes de dos lagunas argentinas fueron estudiadas y comparadas a nivel de comunidad componente e infracomunidad. Se hallaron nueve especies de helmintos, cinco digeneos (Austrodiplostomum cf. mordax, Ascocotyle (Phagicola) cf. diminuta, Ascocotyle sp., Thometrema bonariensis y Saccocoelioides sp.); dos nematodes (Hysterothylacium sp. y Contracaecum sp.); un acantocéfalo (Wolffhugelia matercula) y un cestode (Cangatiella macdonaghi). Odontesthes bonariensis es reportado como un nuevo hospedador para cinco de estas especies. La riqueza específica, la diversidad y la carga parasitaria fueron mas elevadas en la laguna Salada Grande que en la Laguna Lacombe. Esto podría estar relacionado con atributos del cuerpo de agua (tamaño, abundancia de moluscos y aves ictiófagas) y del hospedador (talla y dieta de los pejerreyes capturados en cada laguna). En la laguna Salada Grande, la comunidad de helmintos fue dominada por una especie alogénica y generalista, A. cf. mordax; mientras que en la laguna Lacombe fue dominada por un a especie autogénica y especialista intermedia, C. macdonaghi. El sexo del hospedador no estuvo correlacionado con la riqueza específica, diversidad y carga parasitaria, mientras que la talla del hospedador presentó correlación positiva con estos atributos, excepto la diversidad en la laguna Salda Grande.

A total of 21 pupfish Cyprindon meeki was collected from the spring Abraham González, Durango, Mexico. Seven helminth taxa were recovered: Salsuginus angularis, Posthodiplostomum minimum, Clinostomum complanatum, Bothriocephalus acheilognathi, Cyclustera cf. ralli, Atactorhynchus duranguensis and Spiroxys sp. Among them, B. acheilognathi and A. duranguensis were the most frequent and abundant species. The remaining species were rare and found at low mean abundance. The observed species richness, individual parasite abundance, and diversity were low at component community and infracommunity levels. These features are in accordance with those recorded for other freshwater fish species in the Nearctic part of Mexico. Host feeding habits, along with its role as intermediate host, are suggested as the main factors in determining the helminth community structure in this fish species.

The helminth community of the Mediterranean mouse, Mus spretus, was analysed in a post-fire regenerated Mediterranean ecosystem. The study was carried out in the Spanish Natural Park of the Serra Calderona and comprised a 13 year period, from the 2nd to the 14th year after a wildfire. A total of 121 host individuals was analysed, 66 mice from the burned area and 55 from the non-burned area used as control. The results show a helminth community consisting of 10 helminth species, characterised by low diversity, with Syphacia obvelata as the only dominant helminth species. The helminth infracommunity, determined by its origin of capture, burned or non-burned areas, shows some significant differences. It is concluded that the helminth community of the Mediterranean mouse could be considered as a potential biological tag of the post-fire regeneration in Mediterranean ecosystems and therefore might explain some of the changes occurring and their repercussions in perturbed areas.

Parasite communities of Chionodraco hamatus were investigated from Terra Nova Bay (Ross Sea, Antarctica) during host spawning time. Special attention was given to helminth infracommunities and effect of host sex on its structure. A total of 21 taxa including 5 ecto-parasites and 16 endo-parasites were identified. The number of ecto and endo-parasite species per individual host ranged from 1 to 3 and 3 to 10, respectively, while the mean numbers of parasite specimens per individual host were 4.7 and 1309.7, respectively. The rich abundance of infection suggests a rich concentration of helminth intermediate/paratenic hosts in the coastal waters of Terra Nova Bay. Chionodraco hamatus serves as a definitive host for 10 helminth taxa, while it acts as an intermediate/paratenic host for 6 helminth taxa. Larvae of 6 helminth taxa for which C. hamatus serves as intermediate/paratenic host represented 98.7% of all specimens found. Of these, the tetraphyllidean and diphyllobothridean cestodes and the nematode Contracaecum osculatum s.l. were the most prevalent and abundant. 'Larval' infracommunities had significantly higher species richness, total abundance and diversity than 'adult' infracommunities, suggesting the important role of C. hamatus in supporting the life cycles of those parasites in the study area as a paratenic/intermediate host. Significant differences in the pattern of helminth infracommunities of larval forms between male and female fish were found. These differences could be caused by physiological, and most probably by behavioral differences between sexes suggesting that sex is an important factor influencing parasite burden in C. hamatus during reproductive season.

The helminth communities of silverside, Odontesthes bonariensis (Valenciennes, 1835), from two Argentinean lagoons were studied and compared at component community and infracommunity levels. Nine helminth species were found: five digeneans (Austrodiplostomum cf. mordax, Ascocotyle (Phagicola) cf. diminuta, Ascocotyle sp., Thometrema bonariensis and Saccocoelioides sp.); two nematodes (Contracaecum sp. and Hysterothylacium sp.); one acanthocephalan (Wolffhugelia matercula) and one cestode (Cangatiella macdonaghi). Odontesthes bonariensis is a new host record for five parasite species. Richness, diversity and number of helminths in silversides from Salada Grande lagoon were higher than in those from Lacombe lagoon. This could be related with lagoon size, abundance of mollusks and fish-eating birds, and size and diet of silversides captured in each lagoon. In Salada Grande lagoon the helminth community of silversides was dominated by the allogenic and generalist species A. cf. mordax; while the autogenic and intermediate specialist species C. macdonaghi was dominant in Lacombe lagoon. Host sex did not affect richness, diversity or total abundance, whereas host size was positively correlated with these attributes, except diversity in Salada Grande lagoon., Facultad de Ciencias Naturales y Museo

The main goal of this study was to evaluate the relative influence of season, year of study, host body size, and host sex on abundance of helminth species parasitic in the frog Scinax nasicus. A total of 273 frogs was collected between December 2004 and November 2006 over all seasons in Corrientes City, Province of Corrientes, Argentina. Helminth community included 21 taxa, and was dominated particularly by larval trematodes. Infected frogs harboured a maximum of 7 species. Host sex and season played no significant effect in determining infracommunity parasite species abundance. Similarly, species richness was similar for both host sexes, and across time (year and season). However, occurrence of the parasites Opisthogonimus sp. 2 and Travtrema aff. stenocotyle greatly varied over time. Host body size was the main factor for determining infrapopulation structure of Centrorhynchus sp. Species richness was significantly and positively correlated with host body size. Strong associations were observed mainly between metacercariae of some species. The transmission strategies of parasites suggest that this hylid acquires infections by ingestion of infective larvae and through direct contact with larval parasites from aquatic and terrestrial habitats. Fil: Hamann, Mónika Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Kehr, Arturo Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Gonzalez, Cynthya Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina

We investigated the factors providing structure to the helminth communities of 182 loggerhead sea turtles, Caretta caretta, collected in 6 localities from Central and Western Mediterranean. Fifteen helminth taxa (10 digeneans, 4 nematodes and 1 acanthocephalan) were identified, of which 12 were specialist to marine turtles; very low numbers of immature individuals of 3 species typical from fish or cetaceans were also found. These observations confirm the hypothesis that phylogenetic factors restrict community composition to helminth species specific to marine turtles. There were significant community dissimilarities between turtles from different localities, the overall pattern being compatible with the hypothesis that parasite communities reflect the ontogenetic shift that juvenile loggerheads undergo from oceanic to neritic habitats. The smallest turtles at the putative oceanic, pelagic-feeding stage harboured only the 2 digenean species that were regionally the most frequent, i.e. Enodiotrema megachondrus and Calycodes anthos; the largest turtles at the putative neritic, bottom-feeding stage harboured 11 helminth taxa, including 3 nematode species that were rare or absent in turtles that fed partially on pelagic prey. Mean species richness per host was low (range: 1.60–1.89) and did not differ between localities. Variance ratio tests indicated independent colonization of each helminth species. Both features are expected in ectothermic and vagrant hosts living in the marine environment. L'articolo è disponibile sul sito dell'editore http://www.sciencedirect.com