{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T15:42:02Z","timestamp":1782920522591,"version":"3.54.5"},"reference-count":46,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T00:00:00Z","timestamp":1741046400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Special Research Fund (BOF) of Hasselt University","award":["BOF22DOCLI04"],"award-info":[{"award-number":["BOF22DOCLI04"]}]},{"name":"Special Research Fund (BOF) of Hasselt University","award":["4255-FED-tWIN-G3 program, Prf-2022-049"],"award-info":[{"award-number":["4255-FED-tWIN-G3 program, Prf-2022-049"]}]},{"name":"Hasselt University International and Intersectoral mobility funding\u20142024","award":["BOF22DOCLI04"],"award-info":[{"award-number":["BOF22DOCLI04"]}]},{"name":"Hasselt University International and Intersectoral mobility funding\u20142024","award":["4255-FED-tWIN-G3 program, Prf-2022-049"],"award-info":[{"award-number":["4255-FED-tWIN-G3 program, Prf-2022-049"]}]},{"name":"AfroWetMaP project of the Belgian Federal Science Policy Office","award":["BOF22DOCLI04"],"award-info":[{"award-number":["BOF22DOCLI04"]}]},{"name":"AfroWetMaP project of the Belgian Federal Science Policy Office","award":["4255-FED-tWIN-G3 program, Prf-2022-049"],"award-info":[{"award-number":["4255-FED-tWIN-G3 program, Prf-2022-049"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Clinostomum is a genus of parasitic trematodes found worldwide, infecting a wide range of hosts, including freshwater fishes, snails, birds and occasionally humans. In this study, clinostomid metacercariae were collected from Nile tilapia raised in fish farms in the Upper Tana River region, Kenya. The prevalence of infection was 17.2%, with metacercariae infecting the skin, gills and buccal cavity of the fish. Using light microscopy, scanning electron microscopy (SEM) and molecular methods targeting both nuclear ribosomal (ITS1, 5.8S, ITS2) and mitochondrial (COI) regions, the metacercariae were identified as C. cutaneum, C. phalacrocoracis, C. tilapiae and Euclinostomum heterostomum. The three species of Clinostomum have previously been reported to infect fish or piscivorous birds in Kenya, while this is the first report of E. heterostomum in this country. SEM analysis revealed new ultrastructural features of C. cutaneum, including an excretory pore surrounded by minute spiny papillae, an everted cirrus and dome-shaped papillae on the tegumental area around the genital pore. The cirrus lacked basal papillae, showing morphological variation between the adult and metacercarial stages. Our study, therefore, provides new insights into the phenotypic identification of flukes that may be pathogenic to fishes and humans and, therefore, of scientific and practical importance.<\/jats:p>","DOI":"10.3390\/pathogens14030249","type":"journal-article","created":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T03:26:21Z","timestamp":1741058781000},"page":"249","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Scanning Electron Microscopy Reveals New Ultrastructural Features in Metacercariae of Clinostomum cutaneum (Digenea: Clinostomidae) Infecting Oreochromis niloticus (Actinopterygii: Cichlidae) in Kenya"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7590-4050","authenticated-orcid":false,"given":"Miriam Isoyi","family":"Shigoley","sequence":"first","affiliation":[{"name":"Research Group Zoology: Biodiversity & Toxicology, Centre for Environmental Sciences, Hasselt University, Agoralaan Gebouw D, 3590 Diepenbeek, Belgium"},{"name":"Department of Veterinary Management of Animal Resources, Faculty of Veterinary Medicine, Li\u00e8ge University, 4000 Li\u00e8ge, Belgium"},{"name":"Kenya Wetlands Biodiversity Research Team (KENWEB), Ichthyology Section, National Museums of Kenya, Nairobi 40658-00100, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6554-9545","authenticated-orcid":false,"given":"Nikol","family":"Kmentov\u00e1","sequence":"additional","affiliation":[{"name":"Research Group Zoology: Biodiversity & Toxicology, Centre for Environmental Sciences, Hasselt University, Agoralaan Gebouw D, 3590 Diepenbeek, Belgium"},{"name":"Royal Belgian Institute of Natural Sciences, OD Natural Environment, Freshwater Biology, 1000 Brussels, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel Mungai","family":"Ndegwa","sequence":"additional","affiliation":[{"name":"Kenya Fisheries Service, National Aquaculture Technology Development and Innovations Transfer Centre, Sagana 26-10230, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5522-5755","authenticated-orcid":false,"given":"Martina","family":"Topi\u0107","sequence":"additional","affiliation":[{"name":"Research Group Zoology: Biodiversity & Toxicology, Centre for Environmental Sciences, Hasselt University, Agoralaan Gebouw D, 3590 Diepenbeek, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9350-3752","authenticated-orcid":false,"given":"Kelly J. M.","family":"Thys","sequence":"additional","affiliation":[{"name":"Research Group Zoology: Biodiversity & Toxicology, Centre for Environmental Sciences, Hasselt University, Agoralaan Gebouw D, 3590 Diepenbeek, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3100-7566","authenticated-orcid":false,"given":"Maarten P. M.","family":"Vanhove","sequence":"additional","affiliation":[{"name":"Research Group Zoology: Biodiversity & Toxicology, Centre for Environmental Sciences, Hasselt University, Agoralaan Gebouw D, 3590 Diepenbeek, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1007\/s12571-015-0427-z","article-title":"Feeding 9 Billion by 2050\u2014Putting Fish Back on the Menu","volume":"7","author":"Barange","year":"2015","journal-title":"Food Secur."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1016\/j.worlddev.2015.11.007","article-title":"Contribution of Fisheries and Aquaculture to Food Security and Poverty Reduction: Assessing the Current Evidence","volume":"79","author":"Arthur","year":"2016","journal-title":"World Dev."},{"key":"ref_3","unstructured":"Munguti, J., Obiero, K., Orina, P., Mirera, D., Kyule, D., Mwaluma, J., Opiyo, M., Musa, S., Ochiewo, J., and Njiru, J. 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