Parasitology International最新文献

{"title":"A new species of the genus Henneguya Thélohan, 1892 (Myxozoa: Myxobolidae) parasitizing the gill lamellae of the giant gourami Osphronemus goramy Lacepède (Anabantiformes: Osphronemidae) from the Mekong River Delta, Vietnam","authors":"Nguyen Thi Thu Hang ,&nbsp;Vo Quang Vinh ,&nbsp;Nguyen Dac Dai ,&nbsp;Nguyen Thi Quynh ,&nbsp;Nguyen Manh Hung ,&nbsp;Nguyen Thi Hong Nhung ,&nbsp;Sho Shirakashi ,&nbsp;Nguyen Ngoc Chinh","doi":"10.1016/j.parint.2026.103243","DOIUrl":"10.1016/j.parint.2026.103243","url":null,"abstract":"<div><div>During a survey of myxosporean parasites infecting freshwater fishes in the Mekong River Delta, Vietnam, myxospores of the genus <em>Henneguya</em> were discovered in the gills of the giant gourami <em>Osphronemus goramy</em> Lacepède (Anabantiformes: Osphronemidae). White, spherical plasmodia were found within the gill lamellae of 10 out of 25 examined fish (40% prevalence) and measured 650–950 μm in diameter. Mature myxospores are elongate with two equal caudal appendages, and measure 68.5 ± 3.4 (64.8–79.4) μm in total length. The spore body measures 16.3 ± 0.9 (15.0–18.1) μm in length, 5.6 ± 0.3 (5.1–6.0) μm in width, and 4.8 ± 0.2 (4.5–5.0) μm in thickness. Each caudal appendage is 51.6 ± 3.3 (46.5–58.9) μm in length. The spore wall is smooth, and two equal ovoid nematocysts, each 6.1 ± 0.3 (5.6–6.6) μm long and 1.6 ± 0.2 (1.3–1.8) μm wide, are located anteriorly. Histological sections revealed no inflammatory response but showed local deformation of the gill lamellae at infection sites. Phylogenetic analysis of the SSU rDNA sequences placed this species in a distinct clade closely related to <em>Myxobolus neurophilus</em>, <em>Myxobolus pharyngeus</em>, and <em>Henneguya voronini</em>. Based on morphological and molecular evidence, the parasite is described herein as a new species, <em>Henneguya luci</em> n. sp.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"113 ","pages":"Article 103243"},"PeriodicalIF":1.9,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145990300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toxoplasma gondii and Neospora caninum in naturally infected synanthropic (Muridae) and wild (Cricetidae) rodents from Argentina","authors":"Judith V. Bentancourt Rossoli ,&nbsp;Lucía María Campero ,&nbsp;Gastón Moré ,&nbsp;Agustina Soto-Cabrera ,&nbsp;Dadín P. Moore ,&nbsp;Eleonora L. Morrell ,&nbsp;María V. Scioli ,&nbsp;Walter Basso ,&nbsp;Yanina P. Hecker ,&nbsp;Nathalia P. Scioscia","doi":"10.1016/j.parint.2025.103204","DOIUrl":"10.1016/j.parint.2025.103204","url":null,"abstract":"<div><div>Rodents serve as reservoir hosts for many parasites, including the closely related intracellular protozoan parasites <em>Toxoplasma gondii</em> and <em>Neospora caninum,</em> which are regarded as major causes of abortion in ruminants. This study investigated <em>T. gondii</em> and <em>N. caninum</em> infections in synanthropic (Muridae) and wild (Cricetidae) rodents from rural areas in the Pampas Region, Argentina, using histological, serological, and molecular methods. We also genetically characterized <em>T. gondii</em> isolates. A total of 356 rodents were captured, comprising both murid (<em>Mus musculus, Rattus norvegicus, R. rattus</em>) and cricetid (<em>Oxymycterus rufus, Necromys</em> spp., <em>Akodon azarae, Oligoryzomys flavescens, Calomys musculinus, C. laucha</em>) species. Histological examination did not reveal tissue cysts of these parasites. However, antibodies for <em>T. gondii</em> and <em>N. caninum</em> were detected in 9.8 % (35/356) and 1.7 % (6/356) of the samples using the indirect immunofluorescent antibody test (IFAT). <em>T. gondii</em> DNA was detected by qPCR in brain samples from two of the 41 seropositive rodents. Multilocus PCR-RFLP revealed atypical <em>T. gondii</em> genotypes in both samples. <em>N. caninum</em> DNA was not detected by PCR in any sample. This study provides the first serological and molecular evidence of <em>T. gondii</em> and <em>N. caninum</em> in Cricetidae rodents from Argentina, including the first genotyping data. The detection of <em>T. gondii</em> DNA exclusively in wild rodents highlights the role of wildlife in parasite transmission.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103204"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145687849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First identification of the Africa 4 genotype of toxoplasma gondii in Algeria: Investigation of its origin and rarity","authors":"Nabil Mohamdi ,&nbsp;Sihem Benaissa ,&nbsp;Anis Benyahia ,&nbsp;Karine Passebosc-Faure ,&nbsp;Hélène Yéra ,&nbsp;Gilles Gargala ,&nbsp;Damien Costa ,&nbsp;Loic Favennec","doi":"10.1016/j.parint.2025.103212","DOIUrl":"10.1016/j.parint.2025.103212","url":null,"abstract":"<div><div>Toxoplasmosis, a parasitic infection caused by <em>Toxoplasma gondii</em>, is widely distributed worldwide. Although it generally remains asymptomatic in immunocompetent individuals, it can lead to severe complications in immunocompromised patients, particularly those infected with HIV. These individuals are at increased risk of developing encephalitis, primarily due to the reactivation of a latent infection. Genotyping of <em>T. gondii</em> in humans is an essential tool for studying the epidemiology of this parasitosis. Previous studies have identified three main archetypal (classical) lineages or genotypes: type I, II, and III, as well as strains that show distinct and broader genetic variations.</div><div>In this study, we report for the first time in Algeria the isolation and genetic characterization of the Africa 4 lineage of <em>Toxoplasma gondii</em> using microsatellites genotyping in an HIV-positive patient. This recently described clonal lineage in animal and human highlights the genetic diversity of <em>T. gondii</em>. This work underscores the need for studies to explore the prevalence and distribution of genotypes in the Maghreb region.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103212"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145701441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Host preference of an obligate fish parasitic isopod, Mothocya parvostis","authors":"Kaito Seki ,&nbsp;Ryota Kawanishi ,&nbsp;Atsushi Sogabe","doi":"10.1016/j.parint.2026.103233","DOIUrl":"10.1016/j.parint.2026.103233","url":null,"abstract":"<div><div>The ability to recognize and successfully infest an appropriate host during its early life is under strong natural selection in parasitic organisms, as it directly affects the parasite's fitness. Although many cymothoid isopods that parasitize fishes exhibit high host specificity at the species level, it remains unclear whether the manca (i.e., infective early-life stage) can actively recognize and selectively infest an appropriate host species. We conducted controlled aquarium experiments in which mancae were simultaneously presented with their primary host and a non-primary host species to assess host-selection behavior in the cymothoid isopod <em>Mothocya parvostis</em>, a gill-dwelling species that primarily parasitizes the Japanese halfbeak <em>Hyporhamphus sajori</em> but has also been found at immature stages on several non-primary host fishes. When given a choice between the primary host <em>H. sajori</em> and the non-primary host blackhead seabream <em>Acanthopagrus schlegelii</em>, <em>M. parvostis</em> mancae infested <em>H. sajori</em> significantly more often. When presented with <em>H. sajori</em> and another non-primary host, the largescale blackfish <em>Girella punctata</em>, all infestations occurred exclusively on <em>H. sajori</em>. In contrast, when the two offered host species were non-primary, manca infestation was rare and showed no clear preference between the two fishes. Notably, predation on mancae by non-primary host fishes occurred in a substantial number of trials, whereas no predation by the primary host <em>H. sajori</em> was observed. These findings demonstrate strong host specificity in mancae of <em>M. parvostis</em> toward <em>H. sajori</em>, suggesting that host choice occurs at this early life stage, which likely contributes to enhancing the infestation efficiency.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103233"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145948874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nocardia-derived metabolites as promising antibacterial and larvicidal agents against Anopheles stephensi (Diptera: Culicidae)","authors":"Marjan Seratnahaei ,&nbsp;Saeed Eshraghi ,&nbsp;Fatemeh Safari ,&nbsp;Snigdha Mohan ,&nbsp;Neda Merikhi ,&nbsp;Leila shirani-bidabadi ,&nbsp;Alireza Zahraei-Ramazani","doi":"10.1016/j.parint.2025.103220","DOIUrl":"10.1016/j.parint.2025.103220","url":null,"abstract":"<div><div><em>Nocardia</em> species produce diverse bioactive secondary metabolites, with potential applications against antibiotic resistance and vector-borne diseases. This study characterizes a metabolite from <em>Nocardia fluminea</em> strain N2, isolated from soils in Tehran, Iran, and evaluates its dual antibacterial and larvicidal activities. The strain, identified via 16S rRNA sequencing, and its metabolite production was monitored. Antibacterial efficacy was assessed using agar well diffusion and Minimum Inhibitory Concentration (MIC) assays, while larvicidal toxicity was evaluated by determining the Lethal Concentration 50 (LC₅₀) and 90 (LC₉₀). The metabolite's chemical composition was elucidated using High-Performance Liquid Chromatography (HPLC) and mass spectrometry. The metabolite exhibited potent antibacterial effects, demonstrating significant inhibition zones (&gt;15 mm) and low MIC against <em>Escherichia coli</em> (6.67 μg/mL) and <em>Salmonella typhimurium</em> (2.67 μg/mL). In larvicidal assays against <em>Anopheles stephensi</em>, the metabolite showed time-dependent efficacy, with LC₅₀ values decreasing from 399 mg/L at 24 h to 353 mg/L at 72 h. Structural analysis suggested a novel compound with a molecular weight of 738 Da. Our findings identify the <em>N. fluminea</em> N2 metabolite as a promising dual-function agent for combating bacterial pathogens and malaria vectors.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103220"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145743848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of a trematode infection in an invasive population of Pomacea maculata: Evidence of a phaneropsolid (Trematoda: Microphalloidea) and recommended methods for surveillance","authors":"Jonah A. Nguyen ,&nbsp;Lori Tolley-Jordan ,&nbsp;Annie P. Slayton ,&nbsp;Bradley M. Richardson ,&nbsp;Thomas G. Rosser","doi":"10.1016/j.parint.2025.103203","DOIUrl":"10.1016/j.parint.2025.103203","url":null,"abstract":"<div><div>Giant apple snails, <em>Pomacea maculata</em> (Caenogastropoda: Ampullariidae), are native to South America but are now invasively established in subtropical freshwater habitats worldwide. In May 2017, <em>P. maculata</em> from an urban pond in Mobile, Alabama, USA were found infected with a larval trematode, prompting further collections to determine prevalence and investigate effects of infection by snail sex and size. In total, 284 snails (<em>n</em> = 184 female, <em>n</em> = 100 male) were collected in May, August, and October of 2017 and 2018. Of these, 60 females and 23 males were infected with prevalence per sampling event ranging from 4 to 67 % in females and 0 to 47 % in males. Across all collections, average prevalence was 29.1 %, exceeding values previously reported for <em>Pomacea</em> spp. in their native or invasive ranges. Infection prevalence was positively associated with snail mass, especially in males, suggesting larger individuals are more likely to serve as hosts. Phylogenetic analyses of partial 28S ribosomal DNA sequences identified the trematode as a member of Phaneropsolidae (Microphalloidea), a family that infects ampullariid snails in their native range and includes <em>Phaneropsolus</em> spp., some of which are zoonotic. Comparisons of cercarial morphology against published descriptions complement the molecular results. This is the first report of a trematode infecting an invasive population of <em>P. maculata</em>. These methods and findings demonstrate the utility of simple tissue screening and 28S rDNA sequence data in the rapid detection and molecular identification of larval trematodes collected from invasive populations of snails, facilitated by a newly designed broad-range digenean primer.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103203"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145637503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seroprevalence and associated risk factors of human fascioliasis in Yen Bai and Thanh Hoa provinces, Vietnam","authors":"Thao Thi Bich Nguyen ,&nbsp;Hafid Dahma ,&nbsp;Veronique Dermauw ,&nbsp;Dung Thi Bui ,&nbsp;Bertrand Losson ,&nbsp;Pierre Dorny ,&nbsp;Dung Trung Do ,&nbsp;Olivier Vandenberg","doi":"10.1016/j.parint.2025.103219","DOIUrl":"10.1016/j.parint.2025.103219","url":null,"abstract":"<div><div>Fascioliasis is a zoonotic disease that affects human and animal health worldwide, especially in developing countries. Although fascioliasis is considered an emerging disease in Vietnam, community-based prevalence estimates are scarce. This study aimed to assess the prevalence and risk factors of fascioliasis in northern Vietnam. In 2018, a cross-sectional study was conducted involving 796 individuals from Yen Bai and Thanh Hoa provinces; stool and blood samples were collected from its members. Stool samples were analyzed for <em>Fasciola</em> eggs using the Kato-Katz and formalin-ether concentration techniques, while serum samples were analyzed for anti-<em>Fasciola</em> antibodies using ELISA. All participants aged 15 years and older completed a questionnaire on demographic characteristics and culinary practices. No <em>Fasciola</em> eggs were detected in stool samples (0 %, 95 %CI: 0.00–0.46); however, 2.6 % of participants were seropositive for fascioliasis (21/796, 95 %CI: 1.7 % – 4.0 %). Multivariable logistic regression showed a significantly higher risk of being seropositive among individuals of non-Kinh ethnicity (OR = 14.03, 95 % CI: 2.39–82.17), and among farmers (OR = 3.42, 95 % CI: 1.04–11.25). Lack of awareness about fascioliasis was associated with higher seropositivity (OR = 0.31, 95 %CI: 0.11–0.87). Our findings indicate that fascioliasis is mesoendemic in northern and north central Vietnam. Targeted educational campaigns should explain how transmission can be interrupted.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103219"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145678424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tick saliva molecules as potential immunomodulatory therapeutics","authors":"Takeshi Hatta","doi":"10.1016/j.parint.2025.103224","DOIUrl":"10.1016/j.parint.2025.103224","url":null,"abstract":"<div><div>Ticks, infamous vectors of various pathogens, have evolved a unique strategy of saliva secretion during long-term feeding to suppress host defense mechanisms, including immune responses. This phenomenon may be a potential strategy to treat immune disorders and other diseases, offering a promising opportunity for exploiting parasite biology and parasite-derived molecules in drug discovery. This review examines the therapeutic potential of components in tick saliva, focusing on their mechanisms of action and clinical applications. It also discusses tick-derived immunomodulators, such as chemokine-binding proteins and complement inhibitors, that are currently attracting attention from the perspective of therapeutic drug development. Specifically, <em>Ornithodoros moubata</em> complement inhibitor (nomacopan), a C5 complement inhibitor contained in saliva from the soft tick <em>O. moubata</em>, has reached Phase III clinical trial status for hematopoietic stem cell transplantation-associated thrombotic microangiopathy and is considered an advanced research model in tick-derived drug development. The diverse and potent immunomodulatory properties of tick saliva molecules make them a potentially rich source for the identification and development of novel therapeutics, particularly for immune-mediated diseases.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103224"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145805287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beyond the usual suspects: Uncovering less-recognized pathogenic bacteria in Ghanaian blood-feeding Amblyomma variegatum ticks using 16S rRNA amplicon sequencing","authors":"Jennifer Afua Afrifa Yamoah ,&nbsp;Kofi Dadzie Kwofie ,&nbsp;Jewelna Akorli ,&nbsp;Danielle Ladzekpo ,&nbsp;Hayato Kawada ,&nbsp;Kwadwo Yeboah Boateng ,&nbsp;Julius Beyuo ,&nbsp;Antoinette Keleve ,&nbsp;Jonas Bedford Danquah ,&nbsp;Christopher Tawiah-Mensah ,&nbsp;Jane Ansah-Owusu ,&nbsp;Samuel Kweku Dadzie ,&nbsp;Paul Amponsah Wallace ,&nbsp;Naotoshi Tsuji ,&nbsp;Takeshi Hatta","doi":"10.1016/j.parint.2025.103228","DOIUrl":"10.1016/j.parint.2025.103228","url":null,"abstract":"<div><div>Ticks are important vectors of bacterial pathogens affecting both human and animal health. In Ghana, <em>Amblyomma variegatum</em> is the predominant cattle-infesting tick, yet most studies have focused on a limited range of well-characterized pathogens, potentially overlooking a broader diversity of less-recognized, emerging, or opportunistic bacteria. In this study, we used 16S rRNA amplicon sequencing to characterize the bacteriome of partially blood-fed <em>Am. variegatum</em> ticks, with emphasis on underexplored taxa. As ticks were blood-fed at the time of collection, some detected microorganisms may represent transient, host-derived bacteria rather than endogenous tick microbiota; therefore, findings should also be interpreted within the context of xenosurveillance.</div><div>Partially-fed ticks were collected from cattle across three ecological zones within Ghana's Greater Accra Region. 11 <em>Am. variegatum</em> ticks, confirmed through both morphological and molecular analyses, were subjected to high-throughput sequencing, and bacterial diversity and composition were analysed using established bioinformatics tools. Sequencing generated over 1.75 million high-quality reads and 3172 amplicon sequence variants. Five dominant bacterial phyla were detected, with Actinomycetota and Bacillota being the most abundant. While <em>Rickettsia</em> spp. were prevalent in some samples, <em>Anaplasma</em> and <em>Coxiella</em>, two commonly studied tick-borne bacteria, were not detected. Several less-recognized or opportunistic species, including multidrug-resistant <em>Corynebacterium resistens</em> and bovine-associated <em>Porphyromonas levii</em>, were identified at high relative abundance.</div><div>These findings suggest that <em>Am. variegatum</em> may harbor a broader range of bacterial taxa than previously recognized. Incorporating such neglected microorganisms into a One Health tick-surveillance framework may improve disease risk assessment and guide public and animal health interventions in the region.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103228"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145878799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel diversity and distributions of myxozoans in amphibians from Ecuador with the description of a new species of Cystodiscus","authors":"Gabriela B. Bittencourt-Silva ,&nbsp;Gema Alama-Bermejo ,&nbsp;Rebecca Higham ,&nbsp;Santiago R. Ron ,&nbsp;Beth Okamura ,&nbsp;Jeffrey W. Streicher","doi":"10.1016/j.parint.2025.103218","DOIUrl":"10.1016/j.parint.2025.103218","url":null,"abstract":"<div><div>Among parasites with vertebrate hosts, myxozoans (Cnidaria) remain some of the least studied both taxonomically and geographically. We conducted the first reported surveys for myxozoans from amphibian hosts in Ecuador at two localities: a mid-elevation cloud forest on the Chocó region (western slopes of the Andes) and a lowland Amazonian tropical forest, east of the Andes. We sampled 177 gall bladders and 17 kidneys across the surveys. We found no evidence of myxozoans in the cloud forest site. Myxozoans of the genus <em>Cystodiscus</em> were encountered in the gallbladders of multiple amphibian species from the Amazonian rainforest site, including new host records. Our molecular phylogenies show that, while many of these myxozoans were referable to a clade of <em>C.</em> cf. <em>immersus</em>, we also discovered a divergent lineage of <em>Cystodiscus</em> in the gall bladder of a host that, unlike other known amphibian hosts, has arboreal oviposition. We describe this lineage as a new species, <em>Cystodiscus insperatus</em> n. sp., and infer transmission scenarios consistent with the unique ecology of its frog host. We also report for the first time molecular evidence of a possible new lineage of <em>Sphaerospora</em> living in the kidneys of <em>Osteocephalus taurinus</em> (Anura). Collectively, our study highlights the potential for (i) large biogeographic barriers (like the Andes) to influence the distribution of myxozoans and (ii) intermediate host ecology to drive the evolution of novel lineages of these parasites.</div></div>","PeriodicalId":19983,"journal":{"name":"Parasitology International","volume":"112 ","pages":"Article 103218"},"PeriodicalIF":1.9,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145678369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}