Showing papers on "Digenea published in 2010"

DNA barcodes show cryptic diversity and a potential physiological basis for host specificity among Diplostomoidea (Platyhelminthes: Digenea) parasitizing freshwater fishes in the St. Lawrence River, Canada.

Abstract: Diplostomoid metacercariae parasitize freshwater fishes worldwide and cannot be identified to species based on morphology. In this study, sequences of the barcode region of cytochrome c oxidase subunit 1 (CO1) were used to discriminate species in 1088 diplostomoids, most of which were metacercariae from fish collected in the St. Lawrence River, Canada. Forty-seven diplostomoid species were detected, representing a large increase in known diversity. Most species suggested by CO1 sequences were supported by sequences of internal transcribed spacer (ITS) of rDNA and host and tissue specificity. Three lines of evidence indicate that physiological incompatibility between host and parasite is a more important determinant of host specificity than ecological separation of hosts and parasites in this important group of freshwater fish pathogens. First, nearly all diplostomoid species residing outside the lens of the eyes of fish are highly host specific, while all species that occur inside the lens are generalists. This can be plausibly explained by a physiological mechanism, namely the lack of an effective immune response in the lens. Second, the distribution of diplostomoid species among fish taxa reflected the phylogenetic relationships of host species rather than their ecological similarities. Third, the same patterns of host specificity were observed in separate, ecologically distinctive fish communities.

Acanthocephala, Annelida, Arthropoda, Myxozoa, Nematoda and Platyhelminthes parasites of fishes from the Guandu river, Rio de Janeiro, Brazil

Abstract: Using information from all published reports and data collected during several parasitological surveys between April 2003 and September 2009, a checklist of the parasites of fishes from Guandu River, southeastern of Brazil was generated. A total of 85 parasite species, 54 named species (1 Acanthocephala, 1 Cestoda, 2 Crustacea, 13 Digenea, 11 Nematoda, 23 Monogenea and 3 Myxozoa) and 31 undetermined species (3 Acanthocephala, 2 Cestoda, 1 Crustacea, 8 Digenea, 8 Nematoda, 4 Hirudinea, 3 Monogenea and 2 Myxozoa) in 21 fish host species from Guandu River, were listed in the current study, including 36 new locality records and 36 new host records. Also, a host-parasite list is included herein.

Cryptic species of Euryakaina n. g. (Digenea: Cryptogonimidae) from sympatric lutjanids in the Indo-West Pacific

Abstract: A survey of the endohelminth fauna of Indo-West Pacific Lutjanidae (Perciformes) revealed the presence of the species Siphoderina manilensis (Velasquez, 1961) Miller & Cribb, 2008 and S. marina (Hafeezullah & Siddiqi, 1970) Miller & Cribb, 2008 in seven Lutjanus spp. from sites off the Great Barrier Reef, the Maldives, New Caledonia and Ningaloo Reef, Western Australia. A combination of morphological and ribosomal DNA analyses of these cryptogonimids prompted the transfer of these taxa to a new genus, Euryakaina n. g., as E. manilensis n. comb. and E. marina n. comb., based on comparative analysis with other cryptogonimid taxa. Euryakaina n. g. is distinguished from all other cryptogonimid genera by the combination of a fusiform body, the few relatively small, widely spaced oral spines (sometimes absent), a highly lobed ovary, opposite to slightly oblique testes, vitelline follicles that extend from the anterior margin of the testes to slightly posterior to the intestinal bifurcation, and an excretory vesicle that bifurcates dorsal to the ovary and reunites briefly slightly posterior to the intestinal bifurcation. Morphometric analysis of these taxa alone suggests they should be reduced to synonymy, but DNA sequence analyses and ecological niche partitioning provide evidence that they form a cryptic species complex in sympatric lutjanids in the Indo-West Pacific. The secondary structure of the ITS2 rDNA for species of Euryakaina was also modelled and analysed for the presences of compensatory base changes (CBCs) or hemi-CBCs in order to explore the usefulness of these changes as a tool to help elucidate the taxonomy of this complex system. We also report what we interpret here as intraspecific variation in the ITS2 rDNA between individuals of E. manilensis from Lutjanus vitta recovered off the Great Barrier Reef and New Caledonia.

Metazoan endoparasites of 14 species of skinks (Squamata: Scincidae) from Papua New Guinea

Abstract: Three hundred and three individuals representing 14 species of lizards (Scincidae), collected in Papua New Guinea, were examined for metazoan endoparasites. Two species of Digenea, four species of Cestoda, 21 species of Nematoda (adults and larvae in cysts), two species of Acanthocephala and one species of Pentastomida were found. Forty-two new host records and two new locality records are reported. Skinks from Papua New Guinea are infected by “generalist” endoparasites, which parasitize a variety of reptile or amphibian hosts. Mean endoparasite species diversity per skink species was 5.0 ± 3.3 SD, range: 1–11.

Molecular and experimental evidence refuse the life cycle of Proctoeces lintoni (Fellodistomidae) in Chile

Abstract: The mussel Perumitylus purpuratus has been described as the first intermediate host for the digenea Proctoeces lintoni (Fellodistomidae) in the Chilean coast. The study of more than 3000 specimens of P. purpuratus, taken off northern Chile revealed the absence of sporocysts. Experimental infection of mussels with eggs obtained from the known host for P. lintoni was unsuccessful. We analyze the V4 region of the SSU rRNA of living sporocysts and cercariae obtained from P. purpuratus from central Chile in order to confirm the proposed life cycle for this digenea. Our results demonstrated that sporocysts and cercariae obtained from P. purpuratus do not belong to P. lintoni but to an undescribed digenea from the Chilean coast.

Topography and ultrastructure of the tegument of Bucephalus anguillae (Digenea: Bucephalidae), a parasite of the European eel Anguilla anguilla (Osteichthyen: Anguillidae).

Abstract: The tegumental ultrastructure of the intestinal fluke Bucephalus anguillae was studied with the use of scanning and transmission electron microscopy. The surface of the tegument is covered by transverse ridges from which protrude numerous closely packed, digitated, and claw-shaped spines. Cobblestone-like units of the tegument were observed on the crescent-shaped formation of the rhynchus and at the posterior part of the body. Three types of sensory structures were examined, i.e., 2 uniciliated receptors and 1 without cilia. As anterior-posterior differences were observed, particular attention was given to spines and sensory receptors. Spine insertion zones and average cilia length are variable between anterior and posterior tegument areas. Ultrastructural study revealed that the tegument of B. anguillae has a typical syncytial organization with a distal cytoplasm lying over a basal matrix and cytons below. Cytoplasmic bridges allowed transit of secretory vesicles and granules. Diagrams of spines and sensory receptors were made to help in understanding the nature of these structures.

Discovery of Maritrema jebuensis n. sp. (Digenea: Microphallidae) from the Asian Shore Crab, Hemigrapsus sanguineus, in Korea

Abstract: Maritrema spp. (Digenea: Microphallidae) are parasites of birds, but have not been found in the Republic of Korea. In this study, metacercariae of Maritrema sp. were discovered in the Asian shore crab, Hemigrapsus sanguineus, caught in the mud-flats of Jebu-do, Hwasung-gun, Gyeonggi-do, and the adult flukes were confirmed by experimental infection into mice. Based on the symmetric ribbon-like vitellarium, adult flukes of Maritrema sp. were identified, but did not belong to previously described species in terms of the following morphologic characteristics: ceca reaching to the lateral wall at the anterior border of the ovary; ventral sucker larger than oral sucker; a prominent metraterm; and vitellarium forming a complete ring. Hence, we named this microphallid M. jebuensis n. sp. after the island where the second intermediate hosts were collected. From this study, it has been shown that Maritrema sp. is distributed in Korea and transmitted by the Asian shore crab, H. sanguineus.

A new gorgoderid trematode of the genus Phyllodistomum (Digenea: Gorgoderidae) from Clarias gariepinus (Actinopterygii: Clariidae) in Lake Tana, Ethiopia

Abstract: Phyllodistomum tana sp. nov. is described from the ureters of Clarias gariepinus from Lake Tana, Ethiopia. This species is distinguished from its congeners in Africa in having an oblong body shape, transverse loops of the uterus between the posterior margin of ventral sucker and the vitelline follicles, and the localization exclusively in the ureters of C. gariepinus. The new species differs from P. bavuri and P. vanderwaali in the larger size of body, the position of the testes with respect to the ovary and with each other, the lobed vitelline follicles and the sucker ratio.

Digenea, Strigeidae, Australapatemon canadensis Dubois and Rausch, 1950: first record in South America and a new host record

Abstract: Australapatemon canadensis Dubois and Rausch, 1950 (Digenea, Strigeidae) is reported parasitizing to Cygnus melancoryphus (Molina) (Anatidae) from Lacombe Lagoon, Buenos Aires Province and Pellegrini Lake Rio Negro Province, Argentina. This species is described and compared with related species. The finding of A. canadensis in C. melancoryphus in Argentina represents a new host record extending to South America the geographical distribution of this species.

First record of three species of trematodes of the genus Clinostomum Leidy, 1856 ( Digenea: Clinostomidae) parasitic in piscivorous birds from East Al-Hammar Marsh, South of Iraq

Abstract: Three species of trematodes, genus Clinostomum Leidy, 1856 were described from three different species of piscivorous birds (viz. C. complanatum Leidy, 1856 from grey heron Ardea cinerea and from small white Bittern Ardeola ralloides, C. dasi Bhalerao, 1942 from Bittern Botaurus stellaris and Clinostomum sp. from each of A. cinerea and A. ralloides). Birds were captured from East Al-Hammar marsh, south of Iraq during DecemberFebruary 2004 and December 2005. The genus Clinostomum and its three species were recorded and described as adult for the first time in Iraq. 1Introduction Members of Clinostomum Leidy, 1856, parasite of buccal cavity of aquatic birds, used aquatic snail and fishes (rarely frogs and toads) as first and the second intermediate hosts respectively (Lo et al., 1982). Metacercariae of Clinostomum spp. Have been reported from freshwater fishes of Iraq, but there is no report on adult stage from water birds, only two specimens of immature C. phalacrocoracis Dubios, 1931 was isolated from proventriculous (unusual site for Clinostomum to probability the bird as final host) of pygmy cormorant from AlSweeb Marsh North east of Basrah province by Al-Mayah (1994). Because of shortage of knowledge about final host in N.K. Al-Salim and A.H. Ali / Marsh Bulletin 5(1)(2010)27-42 28 Iraq and such worms infect freshwater and pond fishes (Ali, 2001) this work was done. 2Materials and Methods Twelve Grey heron Ardea cinerea, 7 Bittern Botaurus stellaris, 3 small white heron Ardeola ralloides were collected from two stations, West Al-Hammar Marsh near Suq Al-Shuyukh city (30° 51' N and 40° 46' E), south of Thi Qar province and East Al-Hammar Marsh north of Basrah province (30° 40' N and 47° 33' E) during December-February 2004 and December 2005. The former bird was collected from East Hammar, while the rest were collected from west Al-Hammar marsh. The birds were shot, each individual preserved with ice bags. Some birds transferred to the laboratory alive. Birds were classified according to Allous (1960) and Porter et al.(1996). Buccal cavity of each bird was detected for parasite, the parasites were synthesized by drops of 70 % ethanol, fixed in hot 4% formaldehide , preserved in 70% ethanol, stained with acid carmine and mounted in canada balsam. All drawings were established by aid of a camera lucida fixed on compound microscope type Yaseen at 40-1600 magnification. All measurements are in micrometer unless otherwise stated. Specimens were deposited in the laboratory of parasite of fishes, department of fisheries and marine resources, college of Agriculture. 3Results Three species of adult digenetic trematode of the genus Clinostomum were recorded and described from piscivorous birds, trematodes species and site of infection in the final hosts clarified in table 1. Table (1): Trematodes species, their hosts and site of infection. parasite Site of infection Bird Buccal cavity A. cinerea C. complanatum Pharynx, tongue A. ralloides C. dasi Buccal cavity B. stellaris Clinostomum sp. tongue A. cinerea and A. ralloides N.K. Al-Salim and A.H. Ali / Marsh Bulletin 5(1)(2010)27-42 29 4Descriptions 1Clinostomum complanatum Rud., 1814 Description based on 19 specimens (Fig. 1) Tongue-like body (Fig.1A), concave ventrally 3935-10979(7472) in length. Posterior end wider than anterior end, maximum width 1152-3156(2236) at testes level, the ratio of the length to maximum width 2.2-5.2: 1 (3.4:1). The body has clear constriction at acetabulum level, oral collar well developed 587-978(770) in width, oral sucker small, oval subterminal, 270-474 (356) in length and 261-587(408) in width. Percentage of the oral sucker width to body width 12.5-29.7 (18.9) %. Fore body 6951674(1129). Acetabulum situated in the last half of the first third part of body 360-1420( 793) in length and 463-1394(1065) in width, ratio of width of acetabulum to oral sucker width 1.63-2.6:1(2:1), the percentage of actabulum width to body width 30.1-54.7(40) %. The distance between the suckers 342-1261(774). Esophagus bulb present, esophagus short bifurcated just anterior to acetabulum. Caeca extended to posterior of the body where it is connected to vshaped excretory bladder. Each caeca has many diverticula on exrernal and internal sides, in live specimens the caeca appear brownish or reddish in colour. Testes (fig. 1A,B) triangle shape multilobe, anterior testis turn to left from median longitudinal axis (asymmetrical) and located in posterior second third of body 326-1565(760) in length and 4951210(893) in width, ratio of testis width to its length is 1-2.1(1.3). Posterior testis was symmetrical about the median longitudinal axis 360-717(558) in length and 5581326(1006) in width, ratio of testis width to its length is 1.3-3:1(1.8:1), the distance between testes 135-869(457). Cirrus sac oval (fig. 1B), small 198-721 (563) in length and 180-360(272) in width, between anterior testis and caecum and just above ovary. Genital pore in anterior distal part of cirrus sac opposed to posterior side of anterior testis. Percentage ratio of cirrus length to body length 5.03-13.3(7.6) %. Ovary oval in shape, behind cirrus sac between testes 135-618(382) in length and 162-504(302) in width. Ratio of ovary width to its length is 0.43-1.5:1(0.81:1), ratio of cirrus sac length to ovary length 1.15-1.93:1(1.5:1). Vitellaria global or uniform 51-73×5178(60×75) in measurement, numerous with two lateral fields in distribution except thin circumoral belt absence from it. Vitellaria occupy the space behind acetabulum until posterior end of body. Vitellarial canal and vitellarial receptacle are present between testes, uterus canal open in uterus sac, the latter occupy the area between acetabulum N.K. Al-Salim and A.H. Ali / Marsh Bulletin 5(1)(2010)27-42 30 and anterior testis longitudinally and between caeca transversally, 7563152(1666) in length and 198-935(516) in width. Matured eggs (Fig.1C) 112135(122)×65-81(72) in measurement in uterus and immature eggs between testes. N.K. Al-Salim and A.H. Ali / Marsh Bulletin 5(1)(2010)27-42 31 2Clinostomum dasi Bhalerao, 1942 Description based on one specimen (Fig. 2) Tongue-like body (Fig. 2A), concave ventrally 4415 in length, posterior end wider than anterior end, maximum width 1509 in midbody (mid of anterior testis), ratio of the length to maximum width 2.9: 1, with fine constriction at acetabulum level. Oral collar well developed 396 in width, oral sucker small, rounded subterminal, 226 in the diameter, percentage of oral sucker width to body width 14.97 %. Fore body 651. Acetabulum larger than oral sucker 471 in length and 547 in width in mid of the first third of body, ratio of width of acetabulum to oral sucker width 2.4:1, the percentage of actabulum width to body width 36.6 %. The distance between the suckers 386. Esophagus bulb present, esophagus short bifurcated just anterior to acetabulum, caeca extended to posterior of the body where it is connected to vshaped excretory bladder, each caeca has heavily diverticula on both sides. Testes (fig.1A,B) multilobed, anterior testis in middle of second third of body 471 in length and 792 in width, ratio of testis width to its length is 1.68:1. Posterior testis between second and posterior third of body, but most of it in the second third 566 in length and 792 in width, ratio of testis width to its length is 1.5:1, the distance between testes 339. Cirrus sac (fig.2B) oval, small 283 in length and 169 in width, between anterior testis and caecum and diagonal with ovary, genital pore in anterior distal part of cirrus sac close to anterior testis. Percentage ratio of cirrus length to body length 6.4 %, ovary uniform in shape, diagonal with cirrus sac between testes 264 in length and 151 in width. Ratio of ovary width to its length is 1: 0.57, ratio of cirrus sac length to ovary length 1: 1.07. Vitellaria global, numerous with two lateral fields in distribution except two thin circumoral belts are absent from it, Vitellaria occupy the space between posterior third of acetabulum level until relatively posterior end of body, vitelarial canal and vitelarial receptacle are present between testes, uterus canal open in uterus sac, the latter occupy the space between acetabulum and anterior testis longitudinally and between caeca transversally, Matured eggs (Fig. 2C) 117126(122) in uterus and immatured eggs between testes. 3Clinostomum sp. Description based on three specimen ( 2 complete and one fragment) Elongated oval body (fig. 3A) 84359326(8880) in length, maximum width 1956-2500(2228) at testes region, hind N.K. Al-Salim and A.H. Ali / Marsh Bulletin 5(1)(2010)27-42 32 extremity boarder than anterior one, ratio of length of body to maximum width 3.74.3:1(4:1). Constriction not found in acetabulum region, , oral collar well developed 869-1000(949) in width, oral sucker small and oval, subterminal 304456(358) in length and 391-478(436) in width, percentage ratio of oral sucker to body width 17.6-24.4(21)%. Fore body 1326-1717(1586). Acetabulum larger than oral sucker 810-956(894) in length and 783-846(814) in width in the posterior part of first third of body, many glandular cells in preacetabular region, ratio of width of acetabulum to width of oral sucker 1.912:1(1.95:1). Percentage ratio of acetabulum width to body width 33.8-38(36) %, the distance between suckers 879-1326(1144). Esophagus present, short bifurcated just anterior of acetabulum, caeca extended to posterior of body where connected to v shape excretory vesicle, diverticula in both sides of caeca restricted to post testes region (fig. 3A). Testes (fig. 3A,B) multilobed wider than long, both in the same median of longitudinal axis, anterior testis in posterior part of second third of body 513-765(672) in length and 630-935(833) in width, ratio of anterior testis width to its length is 1.21.26:1(1.23:1). Posterior testis in the anterior part of posterior third of body 369478(423) in length and 666-1413(1040) in width, ratio of

On First Record of a Trematode Parasite of Genus Pleorchis Railliet, 1896 (Digenea: Pleorchiidae Poche, 1926) From Intestine of a Fish, Psettodes erumei (Pleuronectiformes: Psettodidae) From Indian Ocean

Abstract: The genus Pleorchis Railliet, 1896 is designated to rare digenetic distomes living as parasite in the intestine of marine fishes, having numerous testes arranged in four longitudinal rows in hindbody. A total of 14 species have been attributed to the genus, while another 4 species are no longer considered the member of Pleorchis. In this study a new form is described and we critically overviewed the genus. Collection of two ovigerous specimens was recovered live at Deegha, West Bengal, India (Indian Ocean) from the intestine of a marine fish, Psettodes erumei (Bloch & Schneider) out of 40 examined. The present form differs from all nominal species of the Pleorchis in having 48 testes, unequal anterior intestinal caeca, vitellaria extending from a little anterior of ovary up to hind end of body and an entire unlobed ovary. In view of unique morphoanatomical characters it seems that the present form deserves the status of a new species with a specific name Pleorchis srivastavai n. sp. All known species of genus seems to be rare digeneans as evident by their respective studies and these are important link of marine ecosystem.

Serpentoanisocladium sinense n. g., n. sp. (Digenea: Cryptogonimidae) from the eastern water snake Sinonatrix percarinata (Boulenger) (Serpentes: Colubridae) in Guizhou Province, China.

Abstract: Serpentoanisocladium sinense n. g., n. sp. (Digenea: Cryptogonimidae) is described from the intestine of the eastern water snake Sinonatrix percarinata (Boulenger) (Serpentes: Colubridae) from Guizhou Province, China. This digenean is morphologically most similar to members of Anisocladium Looss, 1902 and, to a lesser extent, Anisocoelium Luhe, 1900, which are parasites of marine teleost fish in the Mediterranean and Black Seas. The new genus and species can be differentiated from the two known species of Anisocladium by the position of the vitellarium in relation to the gonads and seminal vesicle, a much longer oesophagus, a shorter caecum only reaching the anterior margin of the anterior testis, the presence of a muscular sucker-like gonotyl, the lack of circumoral spines and the peculiar position of the uterus, which is confined to the same half of the body as the longer caecum. The new genus and species can be differentiated from the only known species of Anisocoelium by the substantially higher body length to width ratio, a much longer oesophagus, the arrangement of the vitelline follicles, the postovarian versus pre-ovarian seminal receptacle, the presence of a well-defined muscular gonotyl and the length of the shorter caecum. A diagnosis of the new genus and a description of the new species are provided. This is the first cryptogonimid found in snakes from China and the first cryptogonimid reported from S. percarinata.

A new species of Tormopsolus (Digenea: Acanthocolpidae) parasite of Genypterus brasiliensis (Teleostei: Ophidiidae) from the Brazilian coast

Abstract: Tormopsolus brasiliensis sp. nov. is described from the intestine of Genypterus brasiliensis Regan, 1903, from Brazil. The new species is characterized mainly by having an almost square terminal oral sucker, a pharynx of the same size or larger than the oral sucker, and testes very close to each other and without vitelline follicles between them. Tormopsolus brasiliensis sp. nov. is most closely related to T. lintoni Caballero, 1952, sharing with the latter the space between the gonads and the distribution of the vitelline fields. It differs from that species by the lack of a space between the gonads and the absence of vitelline follicles between the testes; by the smaller distance between the oral and ventral suckers; by the presence of a wide ejaculatory duct armed with spines; a wide metraterm, almost the same size of the cirrus-sac; and by the shape and terminal position of the oral sucker. Specimens recovered already dead showed distinct differences to the well-fixed, freshly-collected material and are these differences are enumerated. Acanthocolpus brasiliensis of ALVES et al. (2002a,b) is considered synonym of T. brasiliensis sp. nov.