{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T00:54:13Z","timestamp":1791248053372,"version":"4.1.0"},"reference-count":35,"publisher":"American Society of Parasitologists","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal of Parasitology"],"published-print":{"date-parts":[[2024,10,7]]},"abstract":"<jats:p>The structure of the envelopes (capsule and cyst) surrounding metacercariae of Stephanostomum baccatum (Nicoll, 1907) in the second intermediate host, the yellowfin sole Limanda aspera (Pallas 1814), is examined with the methods of light and transmission electron microscopy. The cyst, presumably formed by secretions of the metacercarial tegument, consists of 2 layers: the outer, very thin layer of an electron-dense, finely granular substance and the inner layer composed of loose material of a moderate electron density that includes dense bodies varying in size, shape, and localization. The capsule, formed by the host's cells, is also organized into 2 distinct layers. The inner layer of the capsule is loose, consisting of evenly spaced debris of degenerated cells and lipid droplets with inclusions of intact macrophages between them. The outer layer of the capsule consists of parallel rows of cells arranged around the parasite, with fibroblasts and macrophages being dominant types and granulocytes and lymphocytes found in smaller numbers. Aggregations of collagen fibers are located in narrow spaces between the cells. The number of lipid droplets in the outer layer is significantly smaller than in the inner layer. The capsules formed around the examined trematodes have several structural features that distinguish them from those of S. baccatum and Stephanostomum sp. metacercariae recovered from other fishes of the family Pleuronectidae. The major morphological features of such capsules are the lack of epithelioid or giant multinucleated cells and the presence of numerous lipid droplets. Investigating the structural details of the envelopes surrounding metacercariae in trematodes, as well as other helminths, contributes to our scientific understanding of parasite biology, which can, in turn, have broader implications for understanding host-parasite interactions and evolutionary biology.<\/jats:p>","DOI":"10.1645\/23-86","type":"journal-article","created":{"date-parts":[[2024,10,11]],"date-time":"2024-10-11T07:11:13Z","timestamp":1728630673000},"page":"486-493","source":"Crossref","is-referenced-by-count":1,"title":["Thin and Ultrathin Structure of Envelopes of Stephanostomum baccatum (Trematoda: Acanthocolpidae) Metacercariae in Yellowfin Sole, Limanda aspera"],"prefix":"10.1645","volume":"110","author":[{"given":"E. M.","family":"Skorobrekhova","sequence":"first","affiliation":[{"name":"Institute of Biological Problems of the North FEB RAS, Portovaya str. 18, 685000 Magadan, Russia."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1220","reference":[{"key":"1","doi-asserted-by":"publisher","unstructured":"D. Bock,  \"International Journal for Parasitology.\"  18, \"Formation, histochemistry and ultrastructure of the metacercarial cyst wall of Plagiorhis species 1 (Trematoda, Plagiorchiidae).\" 379 (1988)","DOI":"10.1016\/0020-7519(88)90148-8"},{"key":"2","unstructured":"V. L. Bykov,  \"Cytology and General Histology (Functional Morphology of Human Cells and Tissues).\"  520 (2007)"},{"key":"3","unstructured":"I. A. Chereshnev, V. V. Volobuev, I. E. Khovanskii, et al.  \"Pribrezhnye ryby severnoi chasti Okhotskogo morya (Coastal Fishes of the Northern Part of the Sea of Okhotsk).\"  197 (2001)"},{"key":"4","doi-asserted-by":"publisher","unstructured":"B. S. Dezfuli, C. E. 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The distribution of the metacercaria in eastern Canadian flounders.\" 954 (1954a)","DOI":"10.1139\/f54-054"},{"key":"33","doi-asserted-by":"publisher","unstructured":"R. W. Wolfgang,  \"Journal of the Fisheries Research Board of Canada.\"  11, \"Studies of the trematode Stephanostomum baccatum (Nicoll, 1907): II. Biology, with special reference to the stages affecting the winter flounder.\" 963 (1954b)","DOI":"10.1139\/f54-055"},{"key":"34","doi-asserted-by":"publisher","unstructured":"R. W. Wolfgang,  \"Canadian Journal of Zoology.\"  33, \"Studies of the trematode Stephanostomum baccatum (Nicoll, 1907): III. Its life cycle.\" 113 (1955a)","DOI":"10.1139\/z55-007"},{"key":"35","doi-asserted-by":"publisher","unstructured":"R. W. Wolfgang,  \"Canadian Journal of Zoology.\"  33, \"Studies of the trematode Stephanostomum baccatum (Nicoll, 1907): IV. The variation of the adult morphology and the taxonomy of the genus.\" 129 (1955b)","DOI":"10.1139\/z55-008"}],"container-title":["Journal of Parasitology"],"original-title":[],"deposited":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T00:13:10Z","timestamp":1791245590000},"score":1,"resource":{"primary":{"URL":"https:\/\/bioone.org\/journals\/journal-of-parasitology\/volume-110\/issue-5\/23-86\/Thin-and-Ultrathin-Structure-of-Envelopes-of-Stephanostomum-baccatum-Trematoda\/10.1645\/23-86.full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,10,7]]},"references-count":35,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2024,9,1]]}},"URL":"https:\/\/doi.org\/10.1645\/23-86","relation":{},"ISSN":["0022-3395","1937-2345"],"issn-type":[{"value":"0022-3395","type":"print"},{"value":"1937-2345","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,10,7]]}}}