Distribution Of Vitelline Follicles Research Articles

Neoplagioporus zacconis (Trematoda: Opecoelidae) from the intestine of the pale chub, Zacco platypus, in Korea.

Neoplagioporus zacconis (Yamaguti, 1934) (Trematoda: Opecoelidae) was found from the intestine of the pale chub, Zacco platypus, for the first time in Korea. The worms were characterized morphologically by oval body shape, bipartited seminal vesicle, sinistrally located genital pore, and lobed ovary, and distinguished from the two other species of Neoplagioporous by body shape and distribution of vitelline follicles. The morphological characteristics, except the ovary, well corresponded to those of the previous descriptions. The morphological difference of the ovary was considered as a character of geographical phenotypic variation.

Life-cycle of Euparyphium albuferensis n. sp. (Trematoda: Echinostomatidae) from rats in Spain

The morphology of the different life-history stages and life-cycle of Euparyphium albuferensis are described and drawn. The freshwater snail Gyraulus chinensis (Gastropoda: Planorbidae) serves as the natural and experimental first intermediate host. This and other freshwater snails, such as Lymnaea truncatula, L. peregra, L. palustris and Physa acuta, serve as second intermediate hosts. Adult worms, possessing 45 collar spines, were obtained naturally from Rattus norvegicus and R. rattus, and experimentally from albino rats, mice and golden hamsters. Chickens, ducks and pigeons were not suitable experimental definitive hosts. E. albuferensis differs from the most closely related species, E. murinum Tubangui, 1931, in its larger body, suckers and oesophageal measurements, in the distribution of vitelline follicles and in the morphology of the collar spines.

Bothriocephalus pearsei n. sp. (Cestoda: Pseudophyllidea) from Cenote Fishes of the Yucatan Peninsula, Mexico

The cestode Bothriocephalus pearsei n. sp. is described from the intestine of the cichlid Cichlasoma urophthalmus (Günther) from cenote (= sinkhole) Zaci near Valladolid, Yucatan, Mexico. The pimelodid catfish Rhamdia guatemalensis Günther, which also harbored conspecific cestodes, seems to represent accidental or postcyclic host of B. pearsei. The new species differs from congeners mainly by the morphology of the scolex, which is clavate, with the maximum width in its middle part, has a distinct but weakly muscular apical disc; 2 short and wide bothria distinctly demarcated in their anterior part, becoming indistinct posteriorly in the middle part of the scolex, and 2 elongate, lateral grooves. In addition to the scolex morphology, the new species can be differentiated from Bothriocephalus species parasitizing North American freshwater fishes as follows: B. claviceps (Goeze, 1782), a specific parasite of eels in the Holarctic, B. cuspidatus Cooper, 1917, occurring mostly in perciform fishes in North America, B. musculosus Baer, 1937 found in the cichlid Cichlasoma biocellata (Regan) (= C. octofasciatum (Regan)), and B. texomensis Self, 1954, described from Hiodon alosoides (Rafinesque), are much larger, with strobilae consisting of relatively short and very wide proglottids versus small-sized strobila (length 26-32 mm) composed of about 70 proglottids, which are only slightly wider than they are long (ratio 1:1-3), rectangular, or even longer than wide in the last proglottids in B. pearsei. Bothriocephalus formosus Mueller and Van Cleave, 1932, described from Percopsis omiscomaycus (Walbaum) in the USA, can be distinguished from B. pearsei, besides the different shape of the scolex, by the distribution of vitelline follicles, which are not separated into 2 lateral fields and are present along the midline of proglottids in the former species. Bothriocephalus acheilognathi, a widely distributed parasite of fishes of many families, in particular of cyprinids, distinctly differs from B. pearsei by its arrow- or heart-shaped scolex, larger strobila, and vitelline follicles scattered along the midline of proglottids in the former taxon. Bothriocephalus pearsei is also typified by its fish hosts, which are both of Neotropical origin, and by its geographical distribution limited to isolated deep-lying cenotes of inferior Yucatan.

Host-Induced Morphological Variability in Adult Posthodiplostomum minimum (Digenea: Neodiplostomidae)

Posthodiplostomum minimum adults were collected from natural hosts at Lake Pátzcuaro, Michoacán, México and from experimentally infected hosts. Intraspecific variation was measured using principal component analysis (PCA). Morphological traits such as general body shape, size, and the specific location of certain distinctive organs and structures showed great variation among hosts as described by PCA. These results extend previous studies on host-induced variation in P. minimum in showing that some conservative traits such as vitelline follicle distribution in fore-and hindbody, could be used for an extensive and complete revision of the genus Posthodiplostomum.

Three morphological types of the genus Metagonimus encysted in the dace, Tribolodon taczanowskii, caught from the Sumjin River

Three morphological types of the genus Metagonimus were found encysted in the dace, Tribolodon taczanowskii, caught from the Sumjin River, Korea. They include Metagonimus Yokogawa type (M. yokogawai), Miyata type, and Koga type according to Saito's classification. The metacercariae were experimentally fed to rats and hamsters and a total of 1,624 Metagonimus worms were recovered from their small intestine. The number of each type was 820 for Yokogawa type, 688 for Miyata type, 46 for Koga type, and 70 undetermined. The major differential keys between Yokogawa and Miyata types were in the position of two testes, distribution of uterine tubules, and size of the eggs, and the keys between Miyata and Koga types were in the position of two testes, distribution of vitelline follicles, and size of the eggs. The validity of Miyata type as a specific level should be retained until more convincing evidences are obtained. Koga type is regarded as a synonym of M. takahashii. The present results reveal that there are 3 morphological types of Metagonimus whose larvae are encysted in the dace, T. taczanowskii, from the Sumjin River.

Anantrum histocephalum sp. n. (Cestoda: Bothriocephalidae) from Synodus lucioceps (Synodontidae) of Southern California

Anantrum histocephalum sp. n. is described from Synodus lucioceps, California lizardfish. The larger worm size, mushroom-shaped scolex, vitelline follicle distribution, and larger eggs distinguish this species from A. tortum. The tapeworm was observed in 8.5% of 164 lizardfish from the coastal waters of Los Angeles County.

Studies on the parasitic helminths of Korea: IV. Intestinal trematodes from freshwater mud-turtle (Amyda sinensis Wiegmann) with description of new species, Cotylaspis coreensis.

Cotylaspis coreensis sp. n., Cotylaspis sinensis Faust et Tang, 1936, Phyllodistomum parasiluri Yamaguti, 1934, Kaurma orientalis Yamaguti, 1937, Astiotrema reniferum (Looss, 1898), Astiotrema odhneri Bhalerao, 1936, Astiotrema sp. and Cephalogonimus japonicus Ogata, 1936 were collected from the intestine of freshwater mud-turtle, Amyda sinensis Wiegmann in Korea which were purchased at Namdaemoon Market of Seoul on October 1968 and May 1977. Cotylaspis coreensis differs from other members of the genus in relatively large size of pharynx, the number and distribution of vitelline follicles, size of testis, length of intestine and position of genital opening. Distribution of Cotylaspis sinensis was firstly recorded in Korea. Phyllodistomum parasiluri collected in this study was considered to be the first to recover from the reptilian host although the collected worms were still immatured. The genus Astiotrema collected in this study were divided into three species, A. reniferum which is hitherto unrecorded in Korea, A. odhneri which had been described as A. orientale, A. amydae and A. fukuii and another Astiotrema sp. which differs from the former two species in minor differences in size of suckers, size of ova and size of cirrus pouch. The distribution of Cephalogonimus japonicus was firstly recorded in Korea.