Is Szidat, 1973 (Digenea: Haploporidae) a valid species? Genetic and morphological studies of this controversial species
is a genus within the family Haploporidae and is distributed throughout the Americas. The recent application of molecular techniques has facilitated the reorganization of this genus and the description of new species, resulting in a current total of 28 species. In Argentina, 11 species have been identified; however, the validity of and remains controversial. Recently, specimens of digeneans were collected from two distinct geographical locations: the Paraná River basin (Misiones province) and the Río de la Plata basin (Buenos Aires province). These specimens were found parasitizing two different fish species: and Sequences of the 28S and COI genes were obtained for both digeneans from the two collection sites and hosts. The morphological study, combined with genetic sequences, confirmed their assignment to the genus The COI and 28S gene sequences obtained from specimens at both collection sites exhibited genetic distances of 0.13% and 3.41%, respectively, indicating that these specimens represent a single species. The comprehensive taxonomic study of the newly collected specimens, along with an examination of the type material of and , allows us to confirm the validity of both species. Argentina is home to more than 550 species of freshwater fauna, and it is likely that new species of remain to be discovered in underexplored regions of the basin, such as the Uruguay, Pilcomayo and Bermejo rivers.
Genotyping of benzimidazole resistance using β-tubulin isotype 1 marker in of sheep and goats in Paraná, Southern Brazil
is one of the most pathogenic gastrointestinal parasites that infect small ruminants. The indiscriminate use of anthelmintics (i.e., benzimidazole class, BZ) to control infections has led to the reduction of drug efficacy in populations worldwide. Resistance to BZ is associated with high frequencies of single nucleotide polymorphisms at F200Y, F167Y, and E198A positions of the β-tubulin isotype 1 gene. This study aimed to determine the frequency of single nucleotide polymorphisms associated with BZ resistance in from 18 farms (545 sheep and 124 goats) in Paraná, Southern Brazil. Health management practices were identified as risk factors from individual farms. Genomic DNA was extracted from 20,000 larvae/farm and used in quantitative polymerase chain reaction assays for the three mutations. We ran a correlation analysis between flock health and quantitative polymerase chain reaction data. was the most prevalent parasite in 67% (12/18) of the farms. Resistant allele frequencies were detected for F200Y (var. 46.4 to 72.0%) and F167Y (var. 15.7 to 23.8%). Only (100.0%) susceptible alleles were detected for the E198A. High treatment frequency (15/18), visual weight estimations for anthelmintic dose (15/18), no integration with other farm practices (14/18), treatment of all animals (14/18), and no quarantine period for newly acquired animals (10/18) were considered the most critical risk factors associated with BZ resistance. This is the first systematic prevalence study linking management practices on smallholder farms and the molecular data of BZ resistance of in Southern Brazil.
Characterisation and serodiagnostic evaluation of a recombinant 22.6-kDa tegument protein of
Schistosomosis in animals due to significantly burdens India's livestock economy because of high prevalence and morbidity and is mostly underdiagnosed from the lack of sensitive tools for field-level detection. This study aimed to clone, express the 22.6-kDa tegument protein of (rSs22.6kDa) and to utilise it in a dot enzyme-linked immunosorbent assay for serodiagnosis. RNA was extracted from adult worms recovered from the mesenteries of slaughtered cattle to amplify the gene encoding the 22.6-kDa protein. analysis revealed the protein's secondary structure, consisting of 190 amino acids forming alpha helices (47.89%), extended strands (17.37%), beta turns (8.95%), and random coils (25.79%), with α helices and β sheets in the tertiary structure. Two conserved domains were noted: an EF-hand domain at the N-terminus and a dynein light-chain domain at the C-terminus. Phylogenetic studies positioned the sequence as a sister clade to and The gene was cloned into a pJET vector and transformed into Top 10 cells, with expression achieved using a pET28b vector, BL21 cells, and induction with 0.6 mM isopropyl-β-d-thiogalactopyranoside. The protein's soluble fraction was purified using nickel-chelating affinity chromatography, confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting, identifying a distinct immunodominant 22.6-kDa protein. The diagnostic utility was validated using a dot enzyme-linked immunosorbent assay which demonstrated a of sensitivity of 89.47% and specificity of 100%. The study records for the first time the prokaryotic expression and evaluation of the 22.6-kDa tegumental protein of , highlighting its potential as a diagnostic antigen for seroprevalence studies in bovine intestinal schistosomosis.
Record of Wright, 1954 (Plagiorchiida: Renicolidae) in the Atlantic puffin (Linnaeus, 1758) arrived at the Canary Islands (Spain)
In the winter of 2022-2023, hundreds of the Atlantic puffins () appeared dead in the coast of the Canary Islands, a rare event considering their cold-living habits, normally occupying the North Atlantic Ocean. In this work, investigation about the parasites present in the Atlantic puffins found in the biggest islands of the Archipelago was carried out from a population portion. Necropsies of 39 birds were made and, during the examination of the urinary tracts, helminths were found. Morphoanatomical analysis under microscope allowed to identify them into genus with high similarity to After that, DNA was extracted and NADH dehydrogenase subunit 1 gene were amplificated by a polymerase chain reaction method followed by sequencing and phylogenetic analysis. The molecular results demonstrated that in fact was the helminth parasite present in the urinary tracts of the Atlantic puffins found in the Canary Islands.
Behavioural alterations in surface and cave populations of isopod crustacean by
Acanthocephalans are obligatory endoparasites that often alter the phenotype of their invertebrate intermediate host to facilitate trophic transmission to their final vertebrate host. , a widespread parasite of European freshwater fishes and isopod , was recently discovered also in Postojna-Planina Cave System (Slovenia) parasitising olms () and cave populations of This setting offers a unique opportunity to investigate potential fine-tuning of parasitic manipulations to the specifics of the highly divergent subterranean environment where some common phenotypic alterations lose functionality, but others might gain it. We measured three behavioural traits: movement activity, shelter-seeking, and response to light of infested and uninfested isopods from surface and cave populations. All behaviours were quantified from 1-h video-recordings via video-tracking isopod's movement in empty or custom modified (half-sheltered/half-illuminated) Petri dishes. Infested isopods of both populations spent significantly less time sheltering and were significantly less photophobic than uninfested ones, whereas the activity of isopods was not altered. However, we observed almost no cave-specific responses upon infestation in the two altered behaviours. It seems phenotypic alterations are not particularly fine-tuned to the subterranean environment and its hosts, and likely still reflect the parasite's surface origin.
New insights into the taxonomy and the evolutionary relationships of the rare nematode genus Ferris & Ferris, 1973 (Nematoda, Dorylaimida, Belondiridae), after the molecular characterization of an Iranian population of its type species
A new Iranian population of is characterized, including morphometrics, microphotographs, and molecular (18S, 28S rDNA) studies. It is compared with previously known populations. The results derived from molecular analyses failed to find close evolutionary relationships with other traditional genera of Belondiridae and Swangeriinae, adding more uncertainties about the internal phylogeny of the family. The taxonomy of is revised, with a new diagnosis, list of species, key to their identification, and a compilation of their main morphometrics.
Antioxidant and anti-inflammatory effects of ellagic acid as a new therapy for infection
Trichinellosis is a widespread food-borne zoonosis, causing mild to severe illness in humans with potential fatality. Its treatment remains challenging due to the side effects and limited efficacy of specific drugs. Therefore, the current study was conducted to assess the therapeutic effects of ellagic acid (EA) alone and combined with albendazole against trichinellosis and its biochemical and pathological alterations in mice. Mice were divided into two main groups: G1 and G2 for the intestinal and muscular phases, respectively. Then each group was subdivided into five subgroups: (a) non-infected control, (b) infected control non-treated, (c) infected and treated with EA, (d) infected and treated with albendazole, and (e) infected and treated with a combination of both. Parasitological, biochemical, and histopathological studies were used to evaluate the therapeutic outcomes. Treatment with EA resulted in a significant reduction of the mean counts of intestinal adult worms and muscular larvae compared to the infected control. EA improved oxidative stress as it reduced nitric oxide and increased catalase activities in intestinal and muscular tissues. Additionally, it alleviated the inflammatory response, as evidenced by downregulating IL-6 and increasing IL-10 expressions in tissues. Furthermore, it improved liver functions and ameliorated the pathological alterations induced by trichinellosis. The best results were detected in combination treatments that indicated synergistic effects between EA and albendazole. In conclusion, EA can be used as an anti-inflammatory and antioxidant with a promising anti-parasitic impact against trichinellosis.
A systematic review and meta-analysis on the prevalence of amphistome infection in domestic ruminants in the sub-Saharan Africa region
Systematic review and meta-analysis were conducted to provide comprehensive information on the prevalence of amphistome infections in domestic ruminants in sub-Saharan Africa. A systematic search of peer-reviewed articles published between 2002 and 2023 was conducted. Prevalence estimates and meta-analysis were based on 76 peer-reviewed articles which met the inclusion criteria. Of the 55,122 domestic ruminants screened, 12,858 were infected, and the overall pooled prevalence was 22% (95% confidence interval [CI], 10-37). The highest prevalence was recorded in southern Africa 25% (95% CI, 0-62), and central Africa 16% (95% CI, 0-61) the lowest. Cattle were the most frequently sampled hosts (76.56%, n = 42,202) and sheep (8.78%, n = 4838) the lowest, and cattle recorded the highest pooled prevalence of 28% (95% CI, 12-47), and goats the lowest at 5% (95% CI, 0-14). Prevalence rate was the high in males 32% (95% CI, 21-44), adult ruminants 37% (95% CI, 15-62) and animals with poor body condition 47% (95% CI, 34-60), and during the wet season 36% (95% CI, 0-94). The highest pooled prevalence was recorded at postmortem 23% (95% CI, 8-43) compared to coprology 20% (95% CI, 6-39) studies. The meta-regression model demonstrated that the body condition score, host, and period, and the interactions of different factors significantly influenced the prevalence. The lowest prevalence rate was noted for the period between 2013 and 2023. This is the first systematic review and meta-analysis in sub-Saharan Africa that provides a comprehensive review of the prevalence of amphistome infections in domestic ruminants in the past 20 years.
Description of three new species of von Nordmann, 1832 (Monopisthocotylea: Gyrodactylidae) on species (Nemacheilidae) from Qinghai-Tibet Plateau
Three new species of s were identified from the body surface of the species from the Qinghai-Tibet Plateau, n. sp. on in northern Tibet, n. sp. on and and n. sp. on and in Lanzhou Reach of the Yellow River. The three newly identified species share the nemachili group species' characteristic of having inturning hamulus roots. n. sp. shared a quadrate sickle heel and a thin marginal hook sickle, two morphological traits that set them apart from n. sp. However, they may be identified by the distinct shapes of the sickle base and marginal hook sickle point. n. sp. had much larger opisthaptoral hard part size than the other two species. The three new species show relatively low interspecific differences of 2.9-5.3% p-distance for ITS1-5.85-ITS2 rDNA sequences. Phylogenetic analysis indicated that the three new species formed a well-supported monophyletic group (bp = 99) with the other nemachili group species.
n. sp. (Nematoda: Heteroderinae), a new species of cyst-forming nematode from Southwest China, with a key to the Genus
The cyst nematodes, subfamily Heteroderinae, are plant pathogens of worldwide economic significance. A new cyst nematode of the genus within the Heteroderinae, n. sp., was isolated from rhizospheres of crops in the Guizhou and Sichuan provinces of southwest China. The new species was characterized by having the cyst with a length/width = 1.3 ± 0.1 (1.1-1.6), a fenestral diameter of 28.1 ± 4.3 (21.3-38.7) μm, vulval denticles present; second-stage juvenile with stylet 21.5 ± 0.5 (20.3-22.6) μm long, tail 59.4 ± 2.0 (55.9-63.8) μm long and hyaline region 28.7 ± 2.7 (25.0-36.3) μm long, lateral field with four incisures; the eggshell with punctations. The new species can be differentiated from other species of by a longer tail and hyaline region of second-stage juveniles. Phylogenetic relationships within populations and species of are given based on the analysis of the internal transcribed spacer (ITS-rRNA), the large subunit of the nuclear ribosomal RNA (28S-rRNA) D2-D3 region and the partial cytochrome oxidase subunit I (COI) gene sequences here. The ITS-rRNA, 28S-rRNA and gene sequences clearly differentiated n. sp. from other species of A key and a morphological identification characteristic table for the species of are included in the study.
Genomic characterization of a new species of (Digenea: Allocreadiidae) from Puerto Rico, with comments on the biogeography of the genus
In this study, we describe a new species of (Allocreadiidae) from the mugilid collected in western Puerto Rico, where no allocreadiid has previously been reported, bringing the number of species in this genus to seven (five in , two in spp.). The new parasite species is distinguished from congeners by its overall size, oral-to-ventral sucker size ratio, pharynx size, cirrus sac, and oral lobe morphology, and by 0.64%-3.45% divergence in a 1019-bp alignment of 28S. We build on prior suggestions that the current concept of likely includes multiple species and provide the first mitochondrial data (whole mitochondrial genome) as well as the complete nuclear rDNA array from to facilitate future phylogenetic work. Within the Allocreadiidae, phylogenetic analysis of mitochondrial genomes and 28S provides conflicting topologies for the placement of and The 28S phylogeny of six species of resembles that of four lineages of in that in both host and parasite, Pacific coastal lineages branch earliest, and a Caribbean lineage is more recently evolved.
Morphological and molecular characterization of sp. n. (Nematoda: Mylonchulidae) from Vietnam
sp. n. recorded from Vietnam, is described and illustrated, and its phylogenetic relationship within the Mylonchulidae family and Mononchida order are analysed. The new species is characterized by medium body size (L = 1.0-1.5 mm); buccal cavity goblet shaped, 26-29 × 14-16.5 μm or 1.8 (1.7-1.9) times as long as wide; posterior position of dorsal tooth apex (79%-88% from the base of buccal cavity); a small subventral tooth present on subventral wall with faint and small (2.5 × 1.7 μm) teardrop-shaped pieces, short ; male with short spicules (54-57 μm) with rounded head. The molecular data (18S and 28S rDNA) are provided for the new species.
Narrowing gender gap in the research on echinococcosis and editorial contribution of women in parasitology journals
Gender equity and authorship diversity are believed to be the essential parts of building a dynamic scientific atmosphere. The purpose of the present study was to determine the status of gender equity in research on echinococcosis and the editorial diversity in major parasitology journals over the past four decades. All articles were retrieved from major databases from the years 1980, 2000, 2010, 2015, and 2020. Journals belonging to the four quartiles of parasitology journals listed in the Journal Citation Report were selected, and the gender and region of each editorial member were identified. Among the 3583 first authors of the articles published in all selected years, 2236 (62.4%) were men, whereas 1040 (29%) were women. There was a significant increase in women's contributions as the first author, from 6.8% in 1980 to 35.8% in 2020 ( < .001). A greater gender gap was found for the senior authors, showing 2391 (66.7%) men and 837 (23.4%) women. The gender gap has been narrowed in most of the six regions of the world, particularly for the Western Pacific region, where the gender inequity had almost diminished in 2020; i.e. the man-woman ratios of the first and last authors from this region were 2.25 and 1.75 in 1980, reaching 1.04 and 0.97, in 2020, respectively. Our findings also indicated that articles authored by men received 2.5 to 3.1 times more citations than women authors. Gender distribution of the editors-in-chief, associate editors, and editorial board members across all quartiles showed that 78.7%, 69.5%, and 72.7% were men, respectively, and mostly affiliated with the European and American regions. Findings of the present study showed that gender inequity is still present and women researchers continue to be the minority in the field of parasitology, particularly in the research on echinococcosis.
A new species of (Allocreadiidae) in (Siluriformes) from river streams in fragments of the Atlantic Rainforest, southern Brazil
We described n. sp. from the intestine of the Brazilian catfish (Haseman, 1911) (= ) based on integrative analyses using morphological and molecular approaches. n. sp. closely resembles morphologically Vicente, Santos & Souza, 1978, which was described from a siluriform fish in Northern Brazil; however, the two species differ mainly in the oral and ventral sucker sizes and the distribution of the vitellaria. The phylogenetic analyses of the 28S rDNA placed the sequences of the new species in a monophyletic clade together with all other spp. and as sister taxon of Alcantara, Ebert, Ferreira-Silva, Forti, Morais, Pérez-Ponce de León & Silva, 2024, a parasite from a Brazilian anuran. Genetic divergences between the new species and other spp. varied from 0.2% to 4.3%, further corroborating the distinction of the new taxon. n. sp. is the 18th nominal species known from South America and the 22nd erected in the genus. This is the first study reporting a trematode in spp. hosts and the second parasitological survey carried out for , a poorly known small endemic fish.
sp. nov. (Bothriocephalidae Blanchard, 1849), a cestode parasite of the shorthead lizardfish (Synodontidae) from the Pacific coast of Costa Rica
A new species of bothriocephalid cestode in the genus is described from the intestine of the shorthead lizardfish from the north Pacific coast of Costa Rica. The new species is described based on an integrative taxonomic approach that includes the use of light and scanning electron microscopy, 28S rDNA sequencing, and phylogenetic analysis. sp. nov. is the third known member of this genus and can be distinguished from (Linton, 1905) and Jensen & Heckmann, 1977 by a combination of morphological and ecological traits and, in particular, by having a vaginal sphincter, different number of testes, and different type host and type locality. The molecular analysis and the phylogenetic reconstructions supported its status as a new taxon placing it within a well-supported separate branch of spp. subclade. According to the present finding, represents a new host record and Costa Rica a new geographical record for species, and, in general, for a bothriocephalid cestode.
First report of a morulated Ascaridoidea (Nematoda) egg in an avian coprolite from the Paleogene of the Paraíba Valley, State of São Paulo, Brazil
Ascaridoidea (Nematoda) is a widespread superfamily of nematodes that comprises gastrointestinal parasites from all major groups of vertebrates. Although this taxon probably emerged in the Carboniferous, its Brazilian fossil record includes mostly eggs, found in ancient remains, collected in paleontological and archeological sites from the Mesozoic and Cenozoic Eras. The Tremembé Formation (Oligocene of the Taubaté Basin) has become an important source for paleoparasitological studies in avian coprolites during the third decade of the 21st century, with reports of eggs only at only a single cell stage, of embryonic development. Here we present the first egg of Ascaridoidea preserved containing morula, from a bird coprolite recovered from the shales of the Tremembé Formation. Three coprolites, from the outcrop of Aligra Comércio de Argila S/A, Taubaté municipality (State of São Paulo), were rehydrated and subjected to spontaneous sedimentation. Based on morphological and morphometric features and diet and zoopaleontological context, the trace fossils were assigned to piscivorous birds. The egg found showed morphological characteristics typical of Ascaridoidea: namely spherical form, ornamented, and somewhat thick shell. Moreover, this superfamily includes several taxa that infect piscivorous birds and fish in heteroxenous life cycles and produce eggs with similar features as the egg found in the present study. The paleoparasitological information associated with the paleofaunistic diversity of birds and fish from the Tremembé Formation, reveal that the ancient Brazilian paleoenvironments provided subsidies for the rise and success of nematodes infecting these animals during the Paleogene.
Molecular phylogenetics provides unequivocal support for reclassifying and (Trematoda: Cathaemasiidae) as two valid species with different host preferences
The two stork species that nest in Central Europe, and , have been repeatedly shown to host the digenetic trematode (Rudolphi, 1809) in their esophagus and muscular stomach. These host species differ in their habitat and food preferences, and the morphologic characters of isolates ex and are not identical. These differences led to a previous proposal of two subspecies, C Macko, 1960, and Macko, 1960. We hypothesize that the isolates ex and represent two independent species. Therefore, in the present study, we performed the first molecular analyses of individuals that were consistent with the diagnosis of (ex ) and (ex ). The combined molecular and comparative morphological analyses of the central European individuals ex and led to the proposal of a split of into sensu stricto (formerly ) and sp. n. (formerly ). Morphological analyses confirmed that the length of the vitellaria is the key identification feature of the two previously mentioned species. Both spp. substantially differ at the molecular level and have strict host specificity, which might be related to differences in the habitat and food preferences of the two stork species.
Population dynamics of a South African isolate of liquid culture, using egg yolk as protein source
The entomopathogenic nematode (EPN), , is an effective biological control agent against a variety of important insect pests in South Africa. To develop a South African EPN product feasibly in South Africa, EPNs need to be mass-produced. This study aimed to record the population dynamics of with liquid production in shake flasks, with a protein source of powdered egg yolk. The Erlenmeyer flask results indicated variation between flasks, albeit still achieving high yields. The reasons for attaining such variability in the recovery, yield, and growth stages are unclear, hence requiring further studies seeking to increase consistency. The results obtained indicate that, when IJ recovery is low, yields are also low due to relatively few reproductive adults being present in solution, which, in turn, produces more offspring, which later converts to the desired infective juvenile used for product formulation development. For commercial viability, a consistent production system is required that produces predictable yields. This study showed comparable high yields achieved with the flasks and in an early-stage bioreactor setup, being a positive development for mass production. Prior to the bioreactor scale-up process, protocol of mass production, the population and growth dynamics of the nematodes in the flask environment requires understanding. This is a positive step, leading to the future commercialisation of a local EPN product.
Taxonomic summary of (Cestoda: Bothriocephalidae) with a redescription of (Malhotra, 1983) from India
In this study, we use an integrative taxonomic approach to redescribe (Malhotra, 1983) (Cestoda: Bothriocephalidae), based on newly collected specimens from the type-host (Hamilton, 1822) (Cypriniformes: Danionidae) in Fulbari, Siliguri, West Bengal, India. The detailed morphological assessment, from whole mounts, histology and scanning electron microscopy, offers additional insights into the scolex structure, vitelline follicles, and egg morphology. Molecular data from this and previous studies corroborate the identity and systematics of as a bothriocephalid closely related to the Asian Fish Tapeworm, (Yamaguti, 1934). This study elucidates the historical context and taxonomic ambiguities surrounding , emphasizing the key role of the scolex in both generic and species identification. Amendments to the diagnosis of Akhmerov, 1960 are proposed. A differential diagnosis of the two valid species within the genus, namely and , is also provided. An evaluation of the taxonomic status of Malhotra, 1984, and Malhotra, 1985 suggests that they may be Finally, we posit that none of the ten species of Lönnberg, 1889 described from Indian freshwater teleosts belong to this genus but instead appear to be a mix of species belonging to , Dollfus, 1934, and possibly even Proteocephalidae La Rue, 1911; all require further study based on newly collected, properly fixed specimens and an integrated taxonomic approach. Finally, future survey studies may reveal hidden diversity of species in Indian cyprinoids.
Assessing the diversity of freshwater fish trematodes from Laguna Escondida, Los Tuxtlas tropical rainforest, Mexico, using morphology and 28S rDNA sequences as barcodes
Despite a great effort made for almost 90 years, the diversity of freshwater fish trematodes in Mexico is still far from being fully known. The addition of molecular data to the description of trematode diversity in the last two decades added the potential to establish more robust species limits and a more accurate biodiversity estimation, but also led in some instances to the recognition of cryptic species complexes. Here, we used sequences of the large subunit of the nuclear ribosomal gene (28S rRNA) as barcodes, and morphological data, to assess the diversity of freshwater fish trematodes from a lake within a tropical rainforest. Eighty freshwater fish specimens of eight species were studied, and 120 trematode specimens were collected. Morphologically, specimens were allocated into nine genera; molecular phylogenetic analyses along with sequence divergence data provided evidence for recognising 11 trematode taxa, six adults and five metacercariae; six of them were identified to species level. Geographical distribution and host association patterns are briefly discussed for each trematode taxa.
Morphological and genetic analysis of a rediscovered sp. parasitising and (Cyprinodontiformes: Rivulidae)
Clinostomids are a group of digeneans in which substantial diversity has been recently discovered, with some metacercariae specific to their fish hosts. Genetic analysis has been instrumental in elucidating species diversity within this genus. Recently, seven COI lineages were reported in Argentina, along with three metacercarial morphotypes lacking molecular data. Two of these were found parasitising Rivulidae fishes. The discovery of metacercariae in and from temporary ponds in the western Chacoan region allowed us to redescribe the metacercariae previously identified by other authors and provide the first sequences of this lineage. The morphology of the metacercariae in both hosts matched previously reported descriptions. Genetic analysis clustered the new lineage with , 7, L1, and CRA. This discovery leaves only two morphological records of metacercariae to be characterised using DNA sequencing: one in another Rivulidae () and one in a Loricaridae ( sp.). The present results represent the eighth clinostomid lineage sequenced from Argentina, highlighting the extensive diversity in South America and the many lineages yet to be described or identified, considering that only one of these lineages is formally described based on adult specimens found in the heron