• Parasites, Hosts and Diseases
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• v.26 no.2
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• pp.127-132
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• 1988

Two adult specimens of heterophyid cuke, which belong to the genus Stictodora, were collected from the stool of a 24-year old man after chemotherapy. The nukes were morphologically characterized by their small body siRe (0.90~0.98mm long and 0.38 mm wide) and peculiar structure of ventrogenital sac with armed gonotyl (with about 12~I5 spines) not enveloping genital pore. Species identification is deferred until more worms are obtained, although they closely resemble Stictadora fuscatum (Onji and Nishio, 1916). The Patient used to eat raw flesh of mullets and gobies, which are regarded as the infection source of Stictodora sp., together with 3 other kinds of heterophyids described elsewhere. This is the first record of human Stictodora infection in the literature.

• Applied Microscopy
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• v.30 no.2
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• pp.205-212
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• 2000

Present study was performed to observe the surface ultrastructures of Stictadora furcatum (Trematoda: Heterophyidae). Adult worms were recovered from the cat experimentally infected with metacercariae, and were prepared for scanning electron microscopy. The body was leaf-like and ventrally concave. The oral sucker armed with prominent tegumental spines on the inner surface, and it's lips were obscure. Sensory papillae (type I) in single or grouped forms symmetrically arranged around the oral sucker. The ventrogenital opening retained protruding gonotyl spines and sperms discharged from the genital pore . The body surface was covered with scale-like multipointed tegumental spines. The density and digitated point of spines were gradually decreased toward the posterior end of the body. The digitated points of spines on the anterior portion were 9-12, on the middle were 7-8 and 5-6, and on the posterior were 2-3 and peg-like. Although the tegumental ultrastructure of S. fuscatum was generally similar to those of other heterophyid flukes , the oral sucker with tegumental spines on the inner surface and without obvious lips, and the ventrogenital opening with protruding gonotyl spines were suggested to be the characteristic features.

• Parasites, Hosts and Diseases
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• v.26 no.1
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• pp.55-60
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• 1988

A human case of Centrocestus armatus (Heterophyidae) infection was proved by identifying an adult worm collected after treatment with praziquantel in Korea. The case is 42-year old man who resides in a rural area in Sanchung-gun, Kyeongsangnam·do. The case was concomitantly infected with Clonorchis sinensis and had the history of eating raw (reshwater fishes including Zacco platypus, which are known to be the second intermediate host of C. armatus in Korea. This is the first report of natural human infection by C. armatus in the literature.

• Parasites, Hosts and Diseases
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• v.41 no.2
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• pp.101-105
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• 2003

The metacercariae of Acanthotrema felis Sohn et at., 2003 (Digenea: Heterophyidae) were discovered in a species of the brackish water fish, Acanthogobius flavimanus, in the Republic of Korea. They were experimentally fed to kittens, and adult flukes were harvested 7 days later. The adults were morphologically characterized by the presence of a bipartite seminal vesicle, the ventral sucker associated with a ventrogenital sac enclosing 3 sclerites (2 long and pointed, and 1 short and thumb-like), and an unarmed gonotyl. The adult flukes were identified as A. felis Sohn et al., 2003, and the brackish water fish A. flavimanus has been verified as one of its second intermediate hosts.

• Journal of the korean veterinary medical association
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• v.48 no.1
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• pp.53-63
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• 2012

• Parasites, Hosts and Diseases
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• v.40 no.3
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• pp.107-112
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• 2002

A scanning electron microscopic study was performed on the surface ultrastructure of Pygidiopsis summa (Digenea: Heterophyidae) adults. Metacercariae were collected from gills and muscles of mullets (Mugil cephalus) caught in a known endemic area, and adult flukes were harvested from dogs after 8 weeks of experimental infection. The worm was calabash form with its posterior part broader than the anterior part. Tegumental spines were densely distributed over the body surface, except on the suckers and genital apparatus, and around the excretory pore. Well differentiated spines were observed on the anterior half of the body, with 14-16 tips ventrally, and 19-20 tips dorsally. On the oral sucker. three pairs of type I sensory papillae (uni-ciliated knob-like swellings) and one pair of type II sensory papillae (aciliated round-swellings) were observed on the anterior and posterior parts of the lip, respectively. On the lip of the ventral sucker, one pair of type II sensory papillae was distributed only on its posterior part. Sperms were seen emerging from or entering into the genital apparatus. The results showed that the surface ultrastructure of P. summa was unique among the heterophyid trematodes, especially in digitation of tegumental spines and in distribution of sensory papillae on oral and ventral suckers.

• Parasites, Hosts and Diseases
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• v.29 no.1
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• pp.55-66
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• 1991

A numerical taxonomy was studied on a group of heterophyid trematodes and analysis was made on the following species: Metagonimus yokogawai (3 OTU, Operational Taxonomic Unit) , Metagcnimus Miyata Type (3 OTU), Metagonimus takahashii (2 OTU), Heterophyes dispar (2 OTU), Heterephyes heterophyes (1 OTU), Heterophyes nocens (2 OTV), Heterophyopsis continua (1 OTU), Pygidiopsis summa (3 OTU), Stellantchasmus falcatus (2 OTU) and Stictodora sari (2 OTU). Twenty-six morphological characters were measured and their values were expressed as relative ratios. Similarity and correlation matrix among each individuals were calculated. Clustering analysis by Ward's method and factor analysis were performed using the SAS (Statistical Analysis System) package. As a results, the groups belonging to the genus of Metegenimus were divided into three phonons (Awetegonimus yokogawai, Metegcnimus Miyata Type, M. takahashii) , and Metagonimus Miyata Type was classified as the level of subspecies of M. takahashii. The groups belonging to the genus Heterophyes were clearly divided into three phonons (Heterophyes dispar, H. heterephyes, H. nocens), and H. nccens was classified as not a subspecies level of H. heterophyes but a distinct species. Other species were classified as distinct phonons. From these results, the appllcr lion of numerical taxonomy on trematode classification is considered to be a great aid to determine the limit of taxa.

• Parasites, Hosts and Diseases
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• v.57 no.3
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• pp.257-264
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• 2019

We tried a series of morphological and molecular approaches to identify a new species of Stellantchasmus (Digenea: Heterophyidae) originating from the wrestling half-beaked fish, Dermogenys pusillus of Thailand. Adult worm samples of the new species were recovered from hamsters experimentally infected with the metacercariae from D. pusillus in Thailand. Two isolates (Thai and Korean) of Stellantchasmus falcatus were used as comparative control groups. Worm samples of 3 Stellantchasmus groups were morphologically observed and molecularly analyzed with the mitochondrial cytochrome c oxidase 1 gene. The morphological characteristics of S. dermogenysi n. sp. are similar to S. falcatus originating from brackish water fish, but minor difference was noted including the absence of the prepharynx, position of the ovary near the ceca end, smaller body size, and shorter esophageal length. A phylogenetic tree derived from neighbor-joining and maximum-likelihood methods suggests that S. dermogenysi n. sp. is separated from S. falcatus supported by high bootstrap values. The relative divergences persist between these host-specific trematodes, which we suggest should be recognized as 2 distinct species. Comparisons of S. dermogenysi n. sp. with S. falcatus isolated from mullets in Thailand and Korea indicate a genetic divergence of mitochondrial DNA of 19.4% and 21.7%, respectively. By the present study, a new species, Stellantchasmus dermogenysi n. sp. (Digenea: Heterophyidae), is proposed in Thailand based on molecular evidences, in addition to minor morphological differences between S. falcatus and the new species.

• Parasites, Hosts and Diseases
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• v.23 no.2
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• pp.197-202
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• 1985

During 8 April 1983 to 9 April 1985, a total of 181 domestic cats (Felis catus domestica Linnaeus) of unknown localities in Korea were purchased at Seoul Chung-ang market, and the internal organs were dissected for helminth infections. In the results, three kinds of trematodes of family Heterophyidae (Ohdner, 1914) were obtained from small intestine of domestic cats and identified as follows; five adult worms of Heterophyopsis continua (Onji et Nishio, 1916) from three hosts, two hundreds and twenty three adult worms of Pygidiopsis summa Onji et Nishio, 1916 from seven hosts and twenty six adult worms of Heterophyes heterophyes nocens (Onji et Nishio, 1916) from three hosts. Among them, Heterophyopsis continua and Pygidiopsis summa had not been proved as natural infections of cats in Korea.

• Parasites, Hosts and Diseases
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• v.47 no.3
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• pp.315-318
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• 2009

Quantitative fecal egg counts represented as the number of eggs per gram of feces (EPG) are generally a reliable parameter to estimate the worm burden of intestinal and hepatic parasitoses. Although Haplorchis taichui (Digenea: Heterophyidae) is one of the most common minute human intestinal flukes, little is known about the relationship between EPG and the actual worm burden in patients or the severity of the disease. In the present study, fecal samples were collected from 25 villagers in northern Thailand before and after praziquantel treatment. The EPG values of each participant were determined by the modified cellophane thick smear method, and adult worms were collected from the whole stool after the treatment. Eggs per day per worm (EPDPW) of H. taichui were estimated 82 from egg counts and expelled worms. The EPG was not well correlated with the worm burden, and a reverse correlation was observed between the EPDPW and the worm burden.