Journal of Helminthology最新文献

{"title":"A comprehensive analysis of fasciolosis prevalence and risk factors in humans and animals: First report in Algeria.","authors":"C Fennouh, M Nabi, I Ouchetati, O Salhi, N Ouchene, H Dahmani, A Haif, D Mokrani, N A Khelifi Touhami","doi":"10.1017/S0022149X25000124","DOIUrl":"10.1017/S0022149X25000124","url":null,"abstract":"<p><p>This systematic review and meta-analysis examined 27 studies published between 2003 and 2024 to assess the prevalence of <i>Fasciola hepatica</i> infestation in various animal species in Algeria. Diagnostic methods included liver inspection (16 studies), ELISA (7 studies), coproscopy (4 studies), bile microscopy (1 study), and abattoir data analysis (1 study). For humans, coproscopy and immunoelectrophoresis (IEP) were used in one study in Algiers. Among the 1,006,751 animals examined, 15,868 tested positive, resulting in an overall prevalence of 1.57% (CI 1.55-1.59). Prevalence was higher in the northeastern regions of Algeria (El Tarf, Annaba, and Jijel) at 15.95%, compared to other regions (0.9%-2.95%) (p<0.0001). Cattle showed the highest prevalence (3.91%; CI 3.84-3.98) (p<0.001), followed by sheep (0.42%; CI 0.40-0.44) and goats (0.12%; CI 0.10-0.14). Camels had a prevalence rate of 4%. Trend analysis over 20 years indicated a progressive decrease in prevalence, from 13.29% (2004-2009) to 1.79% (2010-2019) and 1.12% (2020-2024) (p<0.0001). The ELISA method was found to be the most sensitive, revealing a prevalence of 16.40% (CI 15.23-17.57) (true adjusted prevalence is 12.38%) (p<0.0001), significantly higher than liver inspection (1.83%), coproscopy (1.04%), and abattoir data analysis (1.10%). Prevalence increased with animal age across all species. This study clearly shows that fasciolosis in Algeria is most prevalent in the northeast region and that cattle are the high-risk group of animals. As a result, control strategies are urgently needed, targeting cattle in particular in northeast Algeria, to prevent and control this disease and thus reduce Fasciola infection.</p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e26"},"PeriodicalIF":1.6,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143414430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>Echinococcus granulosus</i>' laminated layer immunomodulates nitric oxide, cytokines, and MMPs in PBMC from rheumatoid arthritis patients.","authors":"F Ameur, M Amri, S Djebbara, I Soufli, R-S Boussa, S Benazzouz, I-M Boutemine, S Benkhelifa, M Bouchemal, C Mekhloufi-Dahou, F Hanni, M Yakoubi, S T Lefkir, S Abdellaoui, A Arroul-Lammali, N S Idris, H Belguendouz, C Touil-Boukoffa","doi":"10.1017/S0022149X25000082","DOIUrl":"10.1017/S0022149X25000082","url":null,"abstract":"<p><p>Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that affects the joints. Treatments are symptomatic and can induce side effects in some patients. In this sense and based on previous studies, our aim was to investigate the ex vivo immunoregulatory effect of the laminated layer (LL) during rheumatoid arthritis. LL is the outside layer of parasitic cyst of the helminth <i>Echinococcus granulosus.</i>Our main objective was to study the effect of LL on nitric oxide (NO) and cytokines production, matrix metalloproteinases (MMPs) activities, inducible NO synthase (iNOS) and nuclear factor κappa B (NF-κB) expression. In this context, cultures of peripheral blood mononuclear cells (PBMC) from Algerian RA patients in active (ARA) and inactive (IRA) stage of the disease were stimulated with LL extract (50, 100, 150μg/mL). However, PBMC from ARA patients were stimulated with methotrexate (MTX; 0.5μg/mL) and biological disease modifying anti-rheumatic drugs (bDMARDs): anti-TNFα (10μg/mL), anti-IL6 (10μg/mL), anti-CD20 (10μg/mL), alone or combined with LL (50μg/mL).Our results showed that LL reduced NO, TNF-α, and IL-17A production, MMP9/2 activities, and iNOS/NF-κB expression in PBMC from ARA patients. Concomitantly, LL increases IL-10 and TGF-β1 production in the same cultures. Interestingly, the decrease in NO production induced by bDMARDs was greater in association with LL.Collectively, our findings indicate a strong immunoregulatory effect of LL on NO, MMPs, and cytokines. LL probably acts through the NF-κB pathway. The development of biodrugs derived from LL of <i>E. granulosus</i> could be a potential candidate to modulate inflammation during RA.</p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e21"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fecampiid flatworms parasitic in a tanaidacean crustacean.","authors":"K Kakui, S Shiraki, N Hookabe","doi":"10.1017/S0022149X25000057","DOIUrl":"10.1017/S0022149X25000057","url":null,"abstract":"<p><p>We report the first record of fecampiidan platyhelminths parasitic in tanaidacean crustaceans. Two fecampiidans (0.75 mm and 1.10 mm in length) were found in a female of <i>Pseudotanais</i> sp. (Pseudotanaidae; 1.75 mm in length) collected at 794 m depth off the southern coast of Japan, northwestern Pacific. Fresh individuals were yellow or light yellow, but completely faded in ethanol. In a maximum likelihood tree based on 28S rRNA sequences, the parasite was placed in a moderately-supported Fecampiidae clade, suggesting it is a member of Fecampiidae. The 28S sequence from the parasite was 25.0%, 32.6%, and 35.5% divergent in Kimura 2-parameter (K2P) distance from <i>Fecampia</i> cf. <i>abyssicola</i>, <i>Kronborgia</i> cf. <i>amphipodicola</i>, and <i>Kronborgia isopodicola</i> sequences, respectively.</p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e24"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the complete mitochondrial genomes of <i>Corynosoma bullosum</i> (von Linstow, 1892) and <i>C. evae</i> Zdzitowiecki, 1984 (Acanthocephala: Polymorphida), and the phylogenetic implications.","authors":"Y-Y Xie, H-X Chen, T A Kuzmina, O Lisitsyna, L Li","doi":"10.1017/S0022149X2500001X","DOIUrl":"10.1017/S0022149X2500001X","url":null,"abstract":"<p><p>Species of the genus <i>Corynosoma</i> (Acanthocephala: Polymorphida) mainly parasitize marine mammals and rarely marine birds, and are of veterinary and medical importance due to causing corynosomiasis in wildlife and humans. However, the current knowledge of the mitochondrial genomes and mitogenomic phylogeny of this group remains very insufficient. In the present study, the complete mitochondrial genomes of <i>C. bullosum</i> (von Linstow, 1892) and <i>C. evae</i> Zdzitowiecki, 1984 were sequenced and annotated for the first time. Both mitogenomes comprise 12 protein-coding genes (missing <i>atp8</i>), 22 tRNA genes, and 2 ribosomal RNAs (<i>rrnS</i> and <i>rrnL</i>), plus 2 non-coding regions (<i>NCR1</i> and <i>NCR2</i>). <i>Corynosoma bullosum</i> has the largest mitogenome (14,879 bp) of any polymorphid species reported so far, while <i>C. evae</i> has the smallest (13,947 bp), except for <i>Sphaerirostris lanceoides</i> (Petrochenko, 1949). Comparative mitogenomic analysis also revealed the presence of distinct discrepancies in A + T content and gene rearrangement across the families Polymorphidae, Centrorhynchidae, and Plagiorhynchidae. Moreover, phylogenetic analyses based on the concatenated amino acid sequences of 12 protein-coding genes strongly supported the monophyly of the order Polymorphida and a close affinity between the families Polymorphidae and Centrorhynchidae in Polymorphida. The present mitogenomic phylogeny provides additional evidence for a sister relationship between the genera <i>Corynosoma</i> and <i>Bolbosoma</i> and demonstrated that <i>C. evae</i> has a closer relationship with <i>C. villosum</i> than <i>C. bullosum</i> in the genus <i>Corynosoma.</i></p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e22"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two new marine species of <i>Rhinebothrium</i> (Cestoda: Rhinebothriidea) from stingrays from the Persian Gulf and Gulf of Oman.","authors":"S Omrani, K Golzarianpour, M Malek, M Golestaninasab, Marjan Seiedy","doi":"10.1017/S0022149X24000701","DOIUrl":"10.1017/S0022149X24000701","url":null,"abstract":"<p><p>The genus <i>Rhinebothrium</i> (Cestoda: Rhinebothriidea) comprises tapeworm species parasitizing elasmobranch hosts, particularly batoids. Despite numerous recent findings regarding the ecological importance of marine fish parasites throughout the world, the biodiversity of cestodes inhabiting fishes of the Persian Gulf and the Gulf of Oman remains understudied. Here, two new species of <i>Rhinebothrium</i> from stingrays from the Persian Gulf and Gulf of Oman are described: <i>Rhinebothrium gossi</i> sp. nov. and <i>Rhinebothrium palmeri</i> sp. nov. from <i>Maculabatis arabica</i> and <i>Maculabatis randalli</i>, respectively. However, each new cestode species is found with a lower frequency in the other host species, too. These new species were already subjected to a molecular analysis and the revealed genetic distinctiveness requires detailed morphological examinations at the species level. A combination of morphomeristic characteristics including body size, scolex features, proglottid morphology, and reproductive structures distinguish the new species from the other congeners. Although these new species are morphologically similar, however, they differ from each other in the number of testes (6-8 and 8-14), and bothridial loculi (50 and 42 in <i>R. gossi</i> sp. nov. and <i>R. palmeri</i> sp. nov., respectively). These findings contribute to our understanding of marine cestode diversity and underscore the importance of further research in this ecologically significant region.</p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e18"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthetic camphor derivative (<i>E</i>)-2-((1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)amino)phenol: A novel anthelmintic drug candidate for visceral toxocariasis.","authors":"D C Rodrigues, C N de Oliveira da Cunha, A M Faria, V P Panassolo, L H R Martins, M V N de Souza, M C F D de Souza, L S Munhoz, L F da Costa de Avila, D F Ramos, C J Scaini","doi":"10.1017/S0022149X25000094","DOIUrl":"10.1017/S0022149X25000094","url":null,"abstract":"<p><p>Human toxocariasis is a neglected parasitic disease with a global distribution, treated with current anthelmintics that have low to moderate efficacy, and requires the discovery of novel drugs. Camphor derivatives have antimicrobial properties against various pathogens such as fungi and bacteria. This study aimed to identify a camphor derivative with activity against <i>Toxocara canis</i> larvae and evaluate its cytotoxicity, in silico bioavailability, and in vivo activity in Swiss mice infected with this parasite. Three compounds were tested in vitro in duplicate at a concentration of 1.0 to 0.05 mg/mL in a microplate containing 100 <i>T. canis</i> larvae in RPMI-1640 medium incubated for 48 h at 37°C and 5% CO₂. The compound (E)-2-((1,7,7-trimethylbicyclo [2.2.1] heptan-2-ylidene)amino)phenol (C2) presented a minimum larvicidal concentration (MLC) of 0.25 mg/mL and was selected for the subsequent steps. This compound showed 100% cell viability in MLC and adequate bioavailability in computational models. Two subsequent in vivo tests were performed on Swiss mice inoculated with 500 <i>T. canis</i> infective eggs through intragastric (IG) intubation, one at 10 days post-inoculation (n=5) and the other at 30 days post-inoculation (n=10). The selected compound (10 mg/kg, via IG) and two controls (albendazole, 40 mg/kg, IG and phosphate buffered saline 0,15M, pH 7,2, via IG) were used for this evaluation. The compound reduced the intensity of infection by 75.7% and 54.8% at 10 and 30 days post inoculation, respectively (p<0.05). The results of this study demonstrate that this compound has potential as an anthelmintic candidate for visceral toxocariasis treatment.</p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e19"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydropower reservoirs - their potential association with transmission of trematodes in Vietnam.","authors":"A H Le, H V Nguyen, H Van Hoang, T A Tran, C N Nguyen, B N Nguyen, H T Nguyen, S E Greiman, J R Stauffer, H Madsen, M H Nguyen","doi":"10.1017/S0022149X2400097X","DOIUrl":"10.1017/S0022149X2400097X","url":null,"abstract":"<p><p>The effect of reservoir construction on medically important parasites is well known worldwide but lacks information in Vietnam. With 385 active hydropower plants and numerous water reservoirs, Vietnam provides an ideal setting for studying this issue. This study investigated trematode infection in snail first intermediate hosts from three hydropower reservoirs: Hoa Binh, Son La, and Thac Ba. In total, 25,299 snails representing 16 species were examined, with 959 individuals (8 species) shedding identifiable cercariae. Infection prevalence was highest in thiarid snails (5.4%-15.4%), followed by bithynid snails (2.9%-5.8%). Other snail species showed infection prevalence ranging from 0.3% to 2.9%. Infection prevalence varied significantly across regions, with the highest prevalence in Son La, followed by Hoa Binh and Thac Ba reservoirs. However, no significant differences were observed between snails collected from reservoirs versus canals and paddy fields. Morphological identification resulted in nine cercarial morphotypes, with pleurolophocercaria, xiphidiocercariae, and echinostome being the most common types, accounting for 89.2% of all cercarial infections. Echinostome cercariae were found in seven snail species, while the other cercarial morphotypes were shed by two to five species. <i>Gabbia fuchsiana</i>, <i>Parafossarulus manchouricus</i>, and <i>Melanoides tuberculata</i> were the most common hosts, each harboring five cercarial morphotypes, while Radix auricularia only released echinostome type. In conclusion, our findings highlight the endemic presence of trematodes in hydropower reservoirs and emphasize the need to consider the human-environment interaction around these reservoirs for a better understanding of disease transmission risks.</p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e23"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Previous hookworm infection attenuates the immune response to a subsequent <i>Schistosoma mansoni</i> infection in an experimental model.","authors":"L F V Furtado, L R Serafim, V J da Silva, S R C Dias, N C N de Paiva, C M Carneiro, É M L Rabelo","doi":"10.1017/S0022149X25000033","DOIUrl":"10.1017/S0022149X25000033","url":null,"abstract":"<p><p>This study investigated the co-infection dynamics of <i>Schistosoma mansoni</i> and <i>Ancylostoma ceylanicum</i> in an experimental model. Two experiments were conducted to investigate varying infection orders. In experimental group 1, subjects were initially infected with <i>A. ceylanicum</i>, followed by <i>S. mansoni</i> infection. In group 2, subjects were first infected with <i>S. mansoni</i>, followed by <i>A. ceylanicum</i> infection. The co-infected groups were compared to mono-infected groups for further analysis. Parameters assessed included weight, fecal egg elimination, blood cell counts, IgG response, histopathological analysis, and granuloma morphometry. Results indicated that the timing of infections influenced weight loss. Co-infected animals lost weight similarly to <i>A. ceylanicum</i>-infected animals when <i>A. ceylanicum</i> preceded <i>S. mansoni.</i> The co-infected groups did not experience worsened anemia, despite both parasites being hematophagous. No linear correlation was found between <i>S. mansoni</i> egg counts and anti-SEA IgG production. The response to the <i>S. mansoni</i> adult worm antigen was significantly higher in the <i>S. mansoni</i> mono-infected group compared to the group previously infected with hookworm. Co-infection with <i>A. ceylanicum</i> after <i>S. mansoni</i> infection also interfered with the host response. It caused a delay in the peak of <i>S. mansoni</i> egg elimination compared to the <i>S. mansoni</i> monoinfected group. Additionally, fewer eggs were retained in the liver compared to single infections. These findings help elucidate the interactions between different parasites and their hosts in the same endemic area, providing valuable information to enhance strategies for disease control and management.</p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e16"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can <i>Schistosoma japonicum</i> infection cause liver cancer?","authors":"S Jain","doi":"10.1017/S0022149X24000762","DOIUrl":"10.1017/S0022149X24000762","url":null,"abstract":"<p><p>A co-relation between <i>Schistosoma japonicum</i> (Sj) and liver cancer (LC) in humans has been reported in the literature; however, this association is circumstantial. Due to the inconclusive nature of this association, the International Agency for Research on Cancer has placed Sj in Group 2B for LC, signifying it to be a 'possible carcinogen'. Many epidemiological, pathological and clinical studies have identified multiple factors, linked with Sj infection, which can lead to liver carcinogenesis. These factors include chronic inflammation in response to deposited eggs (which leads to fibrosis, cirrhosis and chromosomal instability at cellular level), hepatotoxic effects of egg-antigens, co-infection with hepatitis viruses, and up-regulation of glycolysis linked genes among others which predisposes hepatic tissue towards malignant transformation. The objective of this work is to present the current understanding on the association of Sj infection with LC. Mechanisms and factors linked with Sj infection that can lead to LC are emphasized, along with measures to diagnose and treat it. A comparison of liver carcinogenesis is also provided for cases linked with and independent of Sj infection. It appears that Sj, alone or with another carcinogen, is an important factor in liver carcinogenesis, but further studies are warranted to conclusively label 'infection with Sj alone' as a liver carcinogen.</p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e11"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supplemental description of <i>Stephanoprora ornata</i> Odhner, 1902 (Digenea: Echinochasmidae) infecting the Nile crocodile, <i>Crocodylus niloticus</i> (Crocodylidae) from Namibia with emendation of <i>Mesorchis</i> Dietz, 1909 and a phylogenetic analysis.","authors":"K Cajiao-Mora, H R Dutton, F J Jacobs, P C Beytell, E C Netherlands, L H DuPreez, S A Bullard","doi":"10.1017/S0022149X25000100","DOIUrl":"10.1017/S0022149X25000100","url":null,"abstract":"<p><p>The synonymies of the echinochasmid genera <i>Mesorchis</i> Dietz, 1909 and <i>Monilifer</i> Dietz, 1909 with <i>Stephanoprora</i> Odhner, 1902 remain contentious and unresolved with morphology. To explore the matter, we herein provide a supplemental description of the type species of <i>Stephanoprora</i>, <i>Stephanoprora ornata</i> Odhner, 1902, based on specimens we collected from the intestine of a Nile crocodile <i>Crocodylus niloticus</i> Laurenti, 1768 (Crocodylia: Crocodylidae) captured in the Kavango River, Namibia. No nucleotide information was available previously for <i>S. ornata.</i> Morphology plus <i>28S</i> and <i>ITS2</i> phylogenetic analyses suggested <i>Stephanoprora</i> is a monotypic genus that can be differentiated from other genera by having 26 collar spines. <i>Stephanoprora</i> differs from <i>Mesorchis</i> by the number and distribution of collar spines (26 [2 dorsal spines, 12 lateral spines, 12 corner spines] vs. 22 [2 dorsal spines, 12 lateral spines, 8 corner spines] in <i>Mesorchis</i>), length of the pre-pharyngeal oesophagus, pharynx position posterior to collar (vs. pre-pharyngeal oesophagus short, pharynx anterior to or at level of corner spines), and testes shape (elongate-ovoid, irregular in outline vs. ovoid, atypically elongated). Our <i>28S</i> and <i>ITS2</i> phylogenies recovered the new sequence of <i>S. ornata</i> (having 26 collar spines) sister to all remaining echinochasmid sequences, representing species that have 20-24 collar spines. <i>Echinochasmus</i> Dietz, 1909 and <i>Mesorchis</i> were recovered as paraphyletic. We retain <i>Monilifer</i> as a junior subjective synonym of <i>Echinochasmus</i> based a suite of morphological features related to body shape and genitalia and because the designated type for <i>Monilifer</i> was reassigned to <i>Echinochasmus.</i> We accept 25 species of <i>Mesorchis.</i></p>","PeriodicalId":15928,"journal":{"name":"Journal of Helminthology","volume":"99 ","pages":"e20"},"PeriodicalIF":1.3,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143382700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}