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At least 19 recordsLinked to original sources
PubMed1983

[Sensillae of cercariae of Haplorchis taichui (Digenea, Heterophyidae). Discussion of the systematics of the Opisthorchioidea].

Cercarial chaetotaxy of Haplorchis taichui (Haplorchiinae, Heterophyidae) is described and compared to that of ten other Opisthorchioidea: three belonging to the Acanthostomidae (Acanthostominae), one to the Opisthorchiidae (Opisthorchiinae) and six to the Heterophyidae (among these, two Centrocestinae, two Apophallinae, one Euryhelminthinae and one Haplorchiinae). Cercarial chaetotaxy allow us to distinguish the considered species and genera, but does not support division of the Opisthorchioidea into families as these have been defined based on morphology of adults; it suggests that the Heterophyidae is heterogenous; it allows us to recognize the Opisthorchioidea characterized by a loss of hexaradial symmetry on the first cephalic cycle of sensillae and by the presence of two to five pairs of sensillae on a tail with proximal excretory apertures.

Animals↗
PubMed1982

[Sensillae and protonephridia of cercaria of Centrocestus formosanus and Centrocestus sp. (Centrocestinae, Heterophyidae)].

A description is given of cercarial chaetotaxy of two Centrocestinae (Heterophyidae, Opisthorchioidea) from Malaysia: Centrocestus formosanus and Centrocestus sp.--Comparison with cercarial chaetotaxy of taxonomically related groups indicates that 1. The chaetotaxy of the Centrocestinae agrees with that of other Opisthorchioidea, 2. There is an important difference between chaetotaxy of Centrocestinae and other Heterophyidae which suggest that the family is heterogeneous.

Animals↗
PubMed2004

Use of rDNA polymorphism for identification of Heterophyidae infecting freshwater fishes.

Infections by trematodes are among the most common fish-borne zoonoses. Metacercariae of the Family Heterophyidae in marine and freshwater fishes are nonfastidious in their choice of definitive hosts, and therefore, cause infections in human and domestic animals. In the present study, species-specific polymerase chain reaction (PCR) assays were developed for identifying and differentiating the various species examined. Sequencing and aligning the 18S (SSU) rDNA revealed interspecific variation for which species-specific DNA oligonucleotides were designed and used for the identification of 6 heterophyid species recovered from piscivorous birds. The oligonucleotides were further used to evaluate the various stages (cercariae recovered from snails, metacercariae recovered from fish and adult trematodes) of the digeneans. By applying this method we elucidated for the first time the life cycle of Pygidiopsis genata. The phylogenetic interrelationship among the newly sequenced species of Heterophyidae is outlined.

Animals↗
PubMed1997

Phagicola longa (Heterophyidae) in dogs from Chile: morphological findings and taxonomical problems.

Trematodes found in the intestines of dogs from Chillan, VIII region of Chile, were studied. The species identified was Phagicola longa, a fluke of the Heterophyidae family, parasites of fish-eating birds or mammals in several countries. P. longa is very similar to P. arnaldoi, a species described in dogs from South America. The number of vitelline follicles and the distribution of cuticular spines are the only distinctive features for the two species. However, many authors report the same number of vitelline follicles for P. arnaldoi and P. longa. Furthermore, the distribution of cuticular spines is very similar. P. longa has a small area devoid of spines when compared to P. arnaldoi but a wide variability of this generic character in the Heterophyidae was observed. As previously reported, P. arnaldoi could be a recent synonym of P. longa, which is the only species of Phagicola that can be found in South American dogs. This is in agreement with the study of metacercariae found in Mugilidae, the intermediate hosts of Phagicola, from American waters in which P. longa is the only species found. The authors emphasize the finding of this trematode in dogs, since it could possibly cause also human infection.

Animals↗
PubMed1992

Scanning electron microscopy of cercariae, metacercariae and adults of Pygidiopsis ardeae Køie, 1990 (Digenea, Heterophyidae).

The penetration apparatus of the cercaria of Pygidiopsis ardeae Køie, 1990 (Heterophyidae) is provided with five large preoral hooklets. Various types of presumably sensory structures surround the small oral aperture. Small, pointed spines protrude throughout the cercarial body. After parasite penetration and encystment in the fish intermediate host, the metacercarial tegument increases its absorptive area by developing irregular projections. Concurrently the pointed spines become scale-like and serrated. The tegumental outgrowths appear to have regressed in infective metacercariae. The external surface of mature worms removed from the intestine of domestic chickens does not differ from that of infective excysted metacercariae. Adults taken from experimentally infected chickens were identical to specimens obtained from naturally infected herons.

Animals↗
PubMed2004

Growth and development of Massaliatrema misgurni (Trematoda: Heterophyidae) in mice and its metacercarial morphology.

The morphology of metacercariae of Massaliatrema misgurni Ohyama et al. (Ohyama et al., Parasitol Int 2001; 50; 267-71) was described, and their infectivity, egg output, growth and development in mice until day 35 post infection (PI) were studied. Metacercarial cysts from loaches imported from China to Japan were 199-349 microm in diameter and consisted of a very thick translucent outer layer and a refractile inner layer. Excysted metacercariae basically had the shape of miniature adults, and a pair of pre-developed testes but no other genital organs were recognized. The worm recovery rate from mice was 36.7-51.7% during days 3-7 PI, and decreased remarkably to 2.5 and 1.7% at days 28 and 35 PI. The prepatent period was 3-4 days, and the egg output quickly increased and sustained high levels at days 5-7 PI, then decreased suddenly at day 8 PI, and continued at a low level until day 28 PI. The size of the body and inner organs such as the oral sucker, pharynx, acetabulum, testes, ovary and seminal receptacle quickly increased until day 3 PI, and sustained at a plateau level until day 21 PI except testes which gradually decreased until 21 PI. The number of the uterine eggs increased with a short time lag compared to other genital organs and sustained a plateau level until day 21 PI. Compared with other Heterophyidae species, M. misgurni was characterized by the remarkably fast growth and development.

Animals↗
PubMed2002

Life cycle and morphology of Metagonimus miyatai (Digenea: Heterophyidae) from Nagano, Japan.

The life cycle of Metagonimus miyatai Saito, Chai, Kim, Lee and Rim, 1997 (Digenea: Heterophyidae) was studied in the Hiroi River at Kotobuki, Iiyama City, Nagano Prefecture, central Japan. Daughter rediae and cercariae were found in Semisulcospira libertina (Gould) and S. dolorosa (Gould) (Gastropoda: Pleuroceridae). Metacercariae were found encysted in Phoxinus lagowskii steindachneri Sauvage (Osteichthyes: Cyprinidae). Cercariae were experimentally exposed to P. lagowskii steindachneri, and metacercariae were obtained from the fish. Metacercariae of natural and experimental infections were experimentally fed to respective golden hamsters, and gravid adults identifiable as M. miyatai were recovered from the small intestine of the golden hamsters. The daughter redia, cercaria, metacercariae and adults are described. The life cycle of M. miyatai is discussed.

Animals↗
PubMed1981

Studies on trematodes of the family Heterophyidae (Odhner, 1914) in Iran: 1. Preliminary epidemiological surveys in man and carnivores in Khuzestan.

Trematodes of the family Heterophyidae in man and carnivores were studied in Khuzestan, south-west Iran. Eight hundred and eleven stool samples from a population of 3400 in 13 villages in a swampy area located in central Khuzestan were examined by the formalin-ether concentration technique. The following helminths were found: Ascaris lumbricoides 7%, Trichostrongylus spp. 53%, hookworms 4+, Trichuris trichiura 5%, Hymenolepis nana 12% and heterophyid spp. 8%. Post-mortem examination of carnivores revealed that 14.2% of jackals, 33.3% of foxes and 2.5% of dogs were infected with heterophyids, namely Metagonimus yokogawai, Heterophyes heterophyes and H. katsuradai. The freshwater snails Melanoides and Melanopsis spp. and brackish water fishes Barbus spp. and Mugil spp. were thought to be the intermediate hosts of these flukes in this area. This is the first report of heterophyid infection in man and carnivores in Iran.

Adolescent↗
PubMed1999

Taxonomic study of Ascocotyle (Phagicola) longa Ransom, 1920 (Digenea: Heterophyidae) and related taxa.

Species of Ascocotyle Looss, 1899 (subgenus Phagicola Faust, 1920) (Digenea: Heterophyidae) related to A. (P.) longa Ransom, 1920, i.e. those with a bipartite gonotyl and a single crown of 16 circumoral spines, were revised on the basis of examination of type and voucher specimens. The species A. (P.) arnaldoi Travassos, 1929, A. (P.) byrdi (Robinson, 1956) and A. (P.) longicollis (Kuntz & Chandler, 1956), all possessing 16 circumoral spines, are synonymised with A. (P.) longa. A. (P.) ascolonga Witenberg, 1929, the types of which were not available, is provisionally retained as a valid species despite its close similarity to A. (P.) longa (identical number of circumoral spines and morphology of the ventrogenital sac). It differs from A. (P.) longa in the presence of uterine loops posterior to the testes and intestinal caeca ending anterior to the ovary (versus the pretesticular uterus and intestinal caeca reaching to the posterior margin of the ovary in A. (P.) longa). A. (P.) inglei (Hutton & Sogandares-Bernal, 1959), found only once in a single specimen, is also tentatively considered a valid species because it differs in number of circumoral spines (19), slightly larger eggs (23-26 x 13-16 microns) and the distribution of refractile bodies of the gonotyl arranged in four separate groups from A. (P.) longa and A. (P.) ascolonga (16 circumoral spines; eggs 15-20 x 8-12 microns; refractile bodies in two groups).

Animals↗
PubMed2000

Description of Acanthotrema armata n. sp. (Trematoda: Heterophyidae) from Larus audouinii (Aves: Laridae), with an amended diagnosis of the genus Acanthotrema Travassos, 1928.

Acanthotrema armata n. sp. (Trematoda: Heterophyidae) is described from the gut of Larus audouinii Payraudeau (Aves: Laridae) caught on the Chafarinas Islands in the southwestern Mediterranean (Spain). This trematode differs from other species of Acanthotrema Travassos, 1928 in having two spined, sclerotised pieces in the ventrogenital sac and in the position of the genital pore. Parastictodora Martin, 1950 is considered a synonym of Acanthotrema. As the diagnosis of the genus Acanthotrema was based only on its type-species, it is amended to include the characteristics of the new species and those attributed to Parastictodora.

Animals↗
PubMed2005

Melanoides tuberculatus (Gastropoda: Thiaridae) as intermediate host of Heterophyidae (Trematoda: Digenea) in Rio de Janeiro metropolitan area, Brazil.

In the late 1960s, Melanoides tuberculatus snails were introduced in Brazil from North/East Africa and Southeast Asia. The first records of specimens infected with cercariae were registered in Rio de Janeiro State in 2001. The present study reports the occurrence of M. tuberculatus infected with larval trematodes in Rio de Janeiro City. Bottom sediment was collected with dip nets and sieved through 0.25 inch-mesh screening. Snails were transported to the laboratory in vials with stream water, then measured and individually isolated in glass vials with distilled water. They were exposed to artificial light and temperature to induce cercarial emergence. The most actively emerging cercariae were processed by differential staining and silver nitrate impregnation methods. Negative snails were subsequently dissected. Approximately 700 snails were collected. Snail total lengths ranged from 1.2 to 3.3 cm. The prevalence rate was 15.76% although 53.76% of the snails were found infected in one of the sites. Infected snails were infected with rediae and pleurolophocercous cercariae. Cercarial morphology and chaetotaxy were consistent with those of the family Heterophyidae mostly due to the presence of median dorsal and ventral fins on the tail and the absence of CI dorsal sensory receptors.

Animals↗
PubMed1989

Identification of Stictodora lari (Heterophyidae) metacercariae encysted in the brackish water fish, Acanthogobius flavimanus.

Metacercariae of the genus Stictodora encysted in the head tissue of Acanthogobius flavimanus (the gobies) caught at Sachun-gun, Kyongnam Province, were identified to be Stictodora lari Yamaguti, 1939 (Trematoda: Heterophyidae), a new parasite fauna in Korea. The metacercariae were 0.39-0.43 mm by 0.32-0.35 mm in size, long elliptical, and with a thin and transparent cyst wall. Total 200 metacercariae were collected from 50 gobies. In order to obtain adult worms two kittens and a puppy were infected each with 34-100 metacercariae, and total 33 adults were recovered between the day 4 and day 8 post-infection. The S. lari adults measured 0.95-1.18 mm long and 0.26-0.32 mm wide and the eggs in uteri 0.028-0.033 mm by 0.017-0.020 mm. The most characteristic morphological feature of these flukes was the presence of a gonotyl and gonotyl spines arranged in two groups; densely crowded group of 30-40 spines and linearly-arranged one of 30-40 spines, together of which made a comma (or reversed comma) shape along the lateral margin of the gonotyl. It has been proved by this study that S. lari is distributed in southern coasts of Korea.

Animals↗
PubMed1992

Surface ultrastructure of Heterophyes nocens (Trematoda: Heterophyidae).

The surface ultrastructure of Heterophyes nocens (Trematoda: Heterophyidae) was studied by scanning electron microscopy(SEM). The adult worms were recovered from experimentally infected cats and from a naturally infected patient. They were leaf-like, ventrally concave, and ovoid or pyriform in shape. Ciliated knob-like sensory papillae (type I) were observed in single or grouped forms on and around the oral sucker, whereas non-ciliated round swellings (type II papillae) were seen on the lip of the ventral sucker. The tegumental spines around the oral sucker were 5-9 pointed, whereas those between the two suckers were 12-17 pointed. Ventrolaterally, three groups of 5-6 type I papillae were located between the oral and ventral suckers, with single ones alternating between them. The genital sucker was protruded or depressed, depending on the contraction state of the flukes, and the gonotyl spine number ranged 50-60. The number of tip points of tegumental spines was decreased posteriorly; finally they became 1-3 pointed. On the dorsal surface, 4 groups of 4-5 type I papillae were symmetrically located on both lateral sides, and the shape and distribution of tegumental spines were similar to those of the ventral surface. Although the tegumental ultrastructure of H. nocens was generally similar to those of other heterophyids, the genital sucker morphology including the number of gonotyl spines and/or the distribution pattern of tegumental spines and sensory papillae were suggested to be the characteristic features of H. nocens.

Animals↗
PubMed1994

The first discovery of an endemic focus of Heterophyes nocens (Heterophyidae) infection in Korea.

A highly endemic focus of human infection with Heterophyes nocens (Heterophyidae) was discovered from a small coastal village of Shinan-gun, Chollanam-do, for the first time in Korea. Fecal examinations by cellophane thick smear and formalin-ether sedimentation techniques revealed 42.9% heterophyid egg positive rate out of 98 inhabitants examined. It was difficult to confirm the species of heterophyids only by eggs. In order to collect the adult flukes, the egg positive cases were treated with 10 mg/kg single dose of praziquantel and purged with magnesium sulfate, and the adult worms were collected from the diarrheic stools. From each of 18 cooperative patients 1 to 1,124 (total 4,730) H. nocens worms were recovered, together with a few to large numbers of heterophyids (Pygidiopsis summa, Stictodora fuscatum) and/or gymnophallids (Gymnophalloides seoi). It is speculated that H. nocens might be widely distributed along the southwestern coastal areas where the brackish water fish such as the mullets or gobies are popularly eaten raw.

Adult↗
PubMed1997

Metagonimus miyatai sp. nov. (Digenea: Heterophyidae), a new intestinal trematode transmitted by freshwater fishes in Japan and Korea.

Metagonimus miyatai n. sp. (Digenea: Heterophyidae) is described based on adult flukes collected from experimental dogs and hamsters fed with metacercariae encysted in the sweetfish, Plecoglossus altivelis, dace, tribolodon hakonensis and T. taczanowskii, common fat-minnow, Morocco steindachneri, pale chub, Zacco platypus, and dark chub, Zacco temmincki, and on those collected from naturally infected humans. The new species was morphologically compared with M. yokogawai and M. takahashii obtained from experimental animals fed with the sweetfish and the crucian carp, Carassius carassius, respectively. The uterine loops of M. miyatai reached near the posterior end of the body through the space between the two testes, whereas those of M. yokogawai, occupied only the space between the acetabulum and anterior border of two testes. This uterine tubule distribution was similar to that of another closely related species, M. takahashii. However, vitellaria of M. miyatai ended in front of the posterior end of the left testis, while those of M. takahashii reached the posterior end of the left testis and ran it over. By raising M. miyatai as a new species, differentiation of M. yokogawai and M. takahashii became very clear. A key to the species of the genus Metagonimus in the Far East has been proposed.

Animals↗
PubMed2002

Surface ultrastructure of Pygidiopsis summa (Digenea: Heterophyidae) adult flukes.

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.

Animals↗
PubMed1999

Redescription of Phagicola pithecophagicola Faust, 1920 (Digenea: Heterophyidae), the type species of Phagicola Faust, 1920.

Phagicola pithecophagicola Faust, 1920, the type species of Phagicola Faust, 1920 (Trematoda: Heterophyidae: Phagicolinae), is redescribed on the basis of examination of type specimens (syntypes) from the monkey-eating eagle, Pithecophaga jeffreyi, from the Philippines. The oral sucker is armed with 1 complete row of 16 circumoral spines (10-19.5 microns long by 4-8 microns wide) and 4 accessory spines (5.5-8 microns long by 3-4 microns wide) on the dorsal side; this arrangement differs from the original description and later redescriptions, where only 12 circumoral spines in 1 row were reported. The ventrogenital sac contains a ventral sucker and a large gonotyl with 2 small, often indistinct, lobes containing a few refractile bodies. The intestinal ceca extend reaching down to the ovarian level. The uterus is confined to the acetabulo-ovarian region, and eggs are 17-20 microns long by 9-10 microns wide.

Animals↗