• 환경생물
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• 제20권4호
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• pp.309-311
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• 2002

A total of ten specimens of darkblotched rockfish, Sebastes crameri obtain-ed from Newport fish market were examined for parasites during February, 2002. Eight out of ten S. crameri were found to be infected with metazoan parasites. They were flatworm Trochopus australis, nematoda Anisakis simplex, and copepods Neobrachiella robusta and Chondracanthus triventricosus. Nine (30.0%) T. australis, seven (30.0%) N. robusta, one (10.0％) C. triventricosus and seven (60.0%) A. simplex were infected. Among them, A. simplex was the most abundant and prevalent metazoan parasites in S. crameri. T. australis and N. robsta were found in gills with moderate intensity (1.7 and 1.9, respectively), and C. triventricosus in dorsal fin with low intensity (0.3).

• Parasites, Hosts and Diseases
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• 제42권4호
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• pp.159-167
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• 2004

Sequences of the complete protein-coding portions of the mitochondrial (mt) genome were analysed for 6 species of cestodes (including hydatid tapeworms and the pork tapeworm) and 5 species of trematodes (blood flukes and liver- and lung-flukes). A near-complete sequence was also available for an additional trematode (the blood fluke Schistosoma malayensis). All of these parasites belong to a large flatworm taxon named the Neodermata. Considerable variation was found in the base composition of the protein-coding genes among these neodermatans. This variation was reflected in statistically-significant differences in numbers of each inferred amino acid between many pairs of species. Both convergence and divergence in nucleotide, and hence amino acid, composition was noted among groups within the Neodermata. Considerable variation in skew (unequal representation of complementary bases on the same strand) was found among the species studied. A pattern is thus emerging of diversity in the mt genome in neodermatans that may cast light on evolution of mt genomes generally.

• Parasites, Hosts and Diseases
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• 제51권6호
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• pp.669-676
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• 2013

Lung fluke, Paragonimus heterotremus, is a flatworm causing pulmonary paragonimiasis in cats, dogs, and humans in Southeast Asia. We examined the ultrastructure of the testis of adult P. heterotremus with special attention to spermatogenesis and spermiogenesis using scanning and transmission electron microscopy. The full sequence of spermatogenesis and spermiogenesis, from the capsular basal lamina to the luminal surface, was demonstrated. The sequence comprises spermatogonia, spermatocytes with obvious nuclear synaptonemal complexes, spermatids, and eventual spermatozoa. Moreover, full steps of spermatid differentiation were shown which consisted of 1) early stage, 2) differentiation stage representing the flagella, intercentriolar body, basal body, striated rootlets, and electron dense nucleus of thread-like lamellar configuration, and 3) growing spermatid flagella. Detailed ultrastructure of 2 different types of spermatozoa was also shown in this study.

• Journal of Species Research
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• 제9권3호
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• pp.269-272
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• 2020

In this study, a species of Rhabdocoela is reported from Korea for the first time. The kalyptorhynch Alcha sinensis Wang & Hu, 2019, was collected from the intertidal zone of Anmyeon Island. Compared to the original study on A. sinensis and previous studies on A. evelinae, we provide additional detail of these two species through pictures of the stylet and a improved description of the prostate stylet type III, which is composed of a bowtie-shaped base and two pairs of heteromorphic plates with fringed or serrated edges. Two plates are also provided with a rounded "blade". Also, we discuss the importance of the prostate stylet type III as a diagnostic character. After a thorough comparison of the descriptions of A. evelinae Marcus, 1949, and A. sinensis, we conclude that the Korean specimens belong to the latter species. Finally, we discuss the difficulties of interpreting diagnostic characters of the small and complex prostate stylet type III within the genus Alcha.