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Results 571 to 600 of 904:

Modulation of human lymphocyte proliferation by salivary gland extracts of ixodid ticks (Acari: Ixodidae): effect of feeding stage and sex

Terézia Rolníková, Mária Kazimírová, Milan Buc

Folia Parasitologica 50[4] 305-312 (2003) | DOI: 10.14411/fp.2003.050

Ixodid ticks remain attached to their hosts for several days to weeks. During this extended feeding process new proteins involved in the modulation of host immune responses are expressed in tick salivary glands. In our study a stimulatory or inhibitory effect of salivary gland extracts (SGE) of unfed and partially fed female Ixodes ricinus (Linnaeus, 1758), female and male Amblyomma variegatum (Fabricius, 1794) and Rhipicephalus appendiculatus Neumann, 1901 ticks on human lymphocyte proliferation induced by Concanavalin A (ConA) and phytohaemagglutinin (PHA), respectively, was investigated. SGE of all female ticks examined suppressed proliferation of ConA-induced lymphocytes; highly significant suppression was observed in the presence of unfed I. ricinus and 9-day fed A. variegatum SGE. SGE of partially fed A. variegatum and I. ricinus females suppressed PHA responses of lymphocytes. Lymphocytes showed reduced PHA and ConA responses in the presence of SGE of unfed and 2-day fed R. appendiculatus females, while SGE of 6-day fed females enhanced PHA responses, but reduced their ConA responses; generally SGE of 2-day fed females displayed the strongest inhibition. Amblyomma variegatum male SGE slightly enhanced PHA, but significantly reduced ConA responses of lymphocytes and their inhibitory effect increased during feeding. SGE of unfed and 2-day fed R. appendiculatus males enhanced PHA and ConA responses and those of 6-day fed males suppressed lymphocyte proliferation. The results suggest that (i) species- and sex-specific differences exist in the effects of tick salivary gland antigens on human lymphocyte proliferation and (ii) effect of SGE on human lymphocyte responses to mitogens varies depending on the tick feeding status.

Hysterothylacium winteri sp. n. (Nematoda: Anisakidae), a parasite of Chilean rock cod, Eleginops maclovinus (Perciformes: Eleginopidae), from South Chile

Patricio Torres, María Soledad Soto

Folia Parasitologica 51[1] 55-60 (2004) | DOI: 10.14411/fp.2004.008

Hysterothylacium winteri sp. n. (Nematoda: Anisakidae) was collected from the intestine of a marine-estuarine fish, Eleginops maclovinus (Valenciennes) (Perciformes: Eleginopsidae), from Abtao in the Gulf of Ancud, Chile. Sixteen (51.6%) out of 31 fish were infected; the intensity was 1-10 (mean 4) worms/host. The new species belongs to the group of congeners possessing one double pair of postanal papillae. By possessing a lateral pair of phasmids situated near the tip of tail, H. winteri most closely resembles Hysterothylacium habena. The new species can be distinguished by the lip flanges forming broadly rounded points and the equal, short spicules (320-400 µm long) representing 0.9-1.7% of body length.

Proliferative renal myxosporidiosis in spawning coho salmon (Oncorhynchus kisutch) in British Columbia and Washington

Simon Jones, Gina Prosperi-Porta, Sheila Dawe, Janice Blackbourn, Kimberley Taylor, Geoffrey Lowe, Andrea Osborn

Folia Parasitologica 51[2/3] 221-227 (2004) | DOI: 10.14411/fp.2004.027

An unidentified myxosporean parasite (CKX) is described from the kidney of approximately 80% of spawning coho salmon Oncorhynchus kisutch (Walbaum) in British Columbia, Canada and Washington, United States of America. Morphological features were described using light and electron microscopy. Sequencing of polymerase chain reaction (PCR) amplified 18S ribosomal RNA gene and in situ hybridisation were used to further characterise CKX. The parasite occurred with a focal distribution within tubule epithelial cells, the tubule lumen and the interstitium as primary cells containing from one to at least 16 secondary cells. Luminal stages were degenerate and sporogony was not observed. In situ hybridisation using a digoxygenin-labelled DNA probe confirmed CKX to be the source of DNA used in PCR analyses. CKX 18S rDNA sequences were most similar (97%) to those of Sphaerospora oncorhynchi. Phylogenetic analysis revealed similarities among the 18S rDNA sequences of CKX, S. oncorhynchi and Myxidium lieberkuehni. CKX is hypothesised to be the abortive extrasporogonic development of a Sphaerospora sp. or Myxidium sp. occurring in immune-incompetent spawning and senescent salmon.

Chigger mites of the genus Eutrombicula Ewing, 1938 (Acari: Trombiculidae) from Cuba, with the description of three new species

Milan Daniel, Alexandr A. Stekol'nikov

Folia Parasitologica 51[4] 359-366 (2004)

Three new species of chigger mites, Eutrombicula cubensis sp. n. and E. anguliscuta sp. n. from lizards and bats, and E. leiocephali sp. n. from lizards, are described. One species, E. lipovskyana (Wolfenbarger, 1953), is recorded for the first time in Cuba. Data on distribution of E. alfreddugesi (Oudemans, 1910) in Cuba are reported.

Morphological features of Prosorhynchus crucibulum and P. aculeatus (Digenea: Bucephalidae), intestinal parasites of Conger conger (Pisces: Congridae), elucidated by scanning electron microscopy

Maria João Santos, David I. Gibson

Folia Parasitologica 49[2] 96-102 (2002) | DOI: 10.14411/fp.2002.019

The external morphology of two bucephalid digenean parasites of Conger conger (Linnaeus) (Congridae, Anguilliformes) caught northwest of the Iberian Peninsula, Prosorhynchus crucibulum (Rudolphi, 1819) Odhner, 1905 and P. aculeatus Odhner, 1905, were studied using scanning electron microscopy (SEM). SEM techniques elucidated new external morphological details, mainly relating to the tegument and protruding organs, such as, in P. crucibulum, a papilla-like structure associated with the pharynx and, in P. aculeatus, the cirrus. The tegument bears scale-like spines, which in both species are arranged quincuncially. The spines of P. crucibulum are wider than long and cover the major part of the body and rhynchus. However, no spines were found in either the central apical depression of the rhynchus or in the middle of the ventral indentation. Also, spines were rarely seen on the tegument around mouth, around the genital aperture or close to the excretory pore. P. aculeatus has spines of a different shape, as wide as they are long and with a rounded margin. They cover the whole body and almost the entire rhynchus, but none were found in the middle of the rhynchus or on its neck region.

Extensive release of an antigen associated with the sporogonic stages of Myxobolus cerebralis (Myxozoa: Myxosporea) is detected by a heterologous antibody raised to Tetracapsuloides bryosalmonae (Myxozoa: Malacosporea)

David J. Morris, Mansour El-Matbouli, Alexandra Adams

Folia Parasitologica 51[2/3] 215-220 (2004) | DOI: 10.14411/fp.2004.026

Monoclonal antibody B4 (mAb B4) was previously developed to the myxozoan parasite Tetracapsuloides bryosalmonae Canning, Curry, Feist, Longshaw et Okamura, 1999, the causative agent of proliferative kidney disease of salmonids. Here we describe the reaction of mAb B4 against Myxobolus cerebralis Hofer, 1903, the parasite that causes 'whirling disease' in salmonids. Tissues examined were collected from experimentally infected rainbow trout Oncorhynchus mykiss (Walbaum) and the aquatic oligochaete Tubifex tubifex (O.F. Müller), the two hosts involved in the life cycle of M. cerebralis. Paraffin sections of infected rainbow trout taken at 4 h and 3, 10, 17 and 54 days post-exposure to infective M. cerebralis actinospores were immunohistochemically stained with mAb B4. Longitudinal sections through infected T. tubifex sampled 120 days post-exposure to M. cerebralis myxospores were also examined using this method. The only phase of the M. cerebralis life cycle that expressed the mAb B4 antigen was during sporogenesis in the salmonid host. The immunohistochemical staining demonstrated that the antigen was released into the tissues surrounding the spore and sporogonic stages of the parasite. The localisation of the antigen was diffuse in the fish, suggesting that the possible effect of M. cerebralis infection is extensive through the head tissues and not limited to areas of cartilage destruction as previously thought.

Ecological analyses of the intestinal helminth communities of the wolf, Canis lupus, in Spain

Juan-Matías Segovia, Ricardo Guerrero, Jordi Torres, Jordi Miquel, Carlos Feliu

Folia Parasitologica 50[3] 231-236 (2003) | DOI: 10.14411/fp.2003.041

This work describes the ecological characteristics of the intestinal helminth communities of 50 wolves (Canis lupus L.) from Spain. The species found were classified into three groups according to prevalence, intensity and intestinal distribution. Taenia hydatigena Pallas, 1766 and Uncinaria stenocephala (Railliet, 1884) are the core species of the community. Taenia multiceps (Leske, 1780) is a secondary species. The rest of the species, Alaria alata (Goeze, 1782), Taenia serialis (Gervais, 1847), Taenia pisiformis (Bloch, 1780), Dipylidium caninum (Linnaeus, 1758), Mesocestoides sp. aff. litteratus, Toxocara canis (Werner, 1782), Toxascaris leonina (von Linstow, 1902), Ancylostoma caninum (Ercolani, 1859) and Trichuris vulpis (Froelich, 1789), behave as satellite species. The linear intestinal distribution of all helminth species was analysed. The location of most species can be considered predictable, especially for core and secondary species. The analysis of interspecific relationships between infracommunities shows that negative associations are more numerous than positive associations. The role of A. caninum in the community is compared with that of U. stenocephala.

Homing of Gyrodactylus salaris and G. derjavini (Monogenea) on different hosts and response post-attachment

Kurt Buchmann, Kenneth K. Madsen, Michael B. Dalgaard

Folia Parasitologica 51[2/3] 263-267 (2004) | DOI: 10.14411/fp.2004.031

In natural European waters, the congeneric monogeneans Gyrodactylus derjavini Mikailov, 1975 and G. salaris Malmberg, 1957 are primarily found on brown trout Salmo trutta L. and Atlantic salmon Salmo salar L., respectively. Interestingly, rainbow trout, Oncorhynchus mykiss (Walbaum), originating from North America, is as susceptible as brown trout to G. derjavini. However, the mechanisms involved in this host specificity are poorly understood but may include behavioural, mechanical and chemical factors affecting parasite attraction, attachment, feeding, reproduction and host responses. In the present laboratory work, this question has been studied. Detached parasites (either G. derjavini or G. salaris) were offered a choice in small aquaria between fry of rainbow trout, Atlantic salmon and carp Cyprinus carpio L. Within 48 hours more than 90% of G. derjavini colonised rainbow trout and left salmon almost uninfected. Some parasites were found on carp. During the same time span, more than 60% of G. salaris attached to salmon, the rest infected rainbow trout and none were found on carp. Following attachment, the parasites need appropriate stimuli to initiate feeding and reproduction but even such a successful specific colonisation can be followed by a host response. Both humoral and cellular elements have been suggested to participate in these reactions but in the present work it was demonstrated by immunoblotting and immunocytochemistry that no antibodies in host mucus and host plasma bound to any parasite structures or epitopes.

Observations on the distribution and biology of Huffmanela huffmani (Nematoda: Trichosomoididae)

Marlin K. Cox, David G. Huffman, František Moravec

Folia Parasitologica 51[1] 50-54 (2004) | DOI: 10.14411/fp.2004.007

The nematode parasite Huffmanela huffmani Moravec, 1987 (Trichosomoididae) infects swimbladders of fishes in the family Centrarchidae. Only fish collected from the upper San Marcos River (Texas) have been found infected with H. huffmani eggs with a prevalence of 90%. Hundreds of thousands of H. huffmani eggs have been observed in these fish but only a few specimens of adult worms have ever been found. The San Marcos River arises from springs along the Balcones Fault Zone in San Marcos, Hays County, Texas. The restriction of the parasite to the upper San Marcos River and the high prevalence of the parasite eggs in centrarchids would seem to enable one to solve the life cycle of H. huffmani but this has proved false. Here, the insights and experiments used to help define some of the aspects concerning the life cycle of this enigmatic parasite are described. This study of H. huffmani includes a description of the habitat, the known limits of geographic distribution of the parasite, possible dispersal processes, egg characteristics, the testing of a possible intermediate host, Palaemonetes antrorum (Benedict) (Decapoda: Palaemonidae), and the effects of the digestion process on H. huffmani eggs.

The phylogeny of marine and freshwater species of the genus Chloromyxum Mingazzini, 1890 (Myxosporea: Bivalvulida) based on small subunit ribosomal RNA gene sequences

Ivan Fiala, Iva Dyková

Folia Parasitologica 51[2/3] 211-214 (2004) | DOI: 10.14411/fp.2004.025

The small subunit ribosomal RNA gene (SSU rDNA) of two freshwater and one marine species of the genus Chloromyxum Mingazzini, 1890 were sequenced. The SSU rDNA trees obtained show the phylogenetic position of the marine species Chloromyxum leydigi Mingazzini, 1890 to be at the base of the freshwater clade, being well supported by a high bootstrap value. Chloromyxum cyprini Fujita, 1927 is closely related to Chloromyxum truttae Léger, 1906 and they represent a sister branch to raabeia sp., Myxidium sp. and Myxidium truttae Léger, 1930. Chloromyxum legeri Tourraine, 1931 is in a position ancestral to Myxidium lieberkuehni Bütschli, 1882 and Sphaerospora oncorhynchi Kent, Whitaker et Margolis, 1993. Three newly sequenced species of the genus Chloromyxum represent three separate lineages within the myxosporean tree and do not support the monophyly of this genus.

Redescription of Dracunculus globocephalus Mackin, 1927 (Nematoda: Dracunculidae), a parasite of the snapping turtle, Chelydra serpentina

František Moravec, M.D. Little

Folia Parasitologica 51[4] 339-345 (2004)

Dracunculus globocephalus Mackin, 1927 (Nematoda: Dracunculoidea) is redescribed from specimens collected from the mesentery of the snapping turtle, Chelydra serpentina (L.), in Louisiana, USA. The use of scanning electron microscopy, applied for the first time in this species, made it possible to study details in the structure of the cephalic end and the arrangement of male caudal papillae that are difficult to observe under the light microscope. This species markedly differs from all other species of Dracunculus in having the spicules greatly unequal in size and shape, in the absence of a gubernaculum, and in the disposition of male caudal papillae. The validity of D. globocephalus is confirmed, but the above mentioned morphological differences are not sufficient for listing it in a separate genus. This is the first record of D. globocephalus in Louisiana.

Review of the Rhopalothylacidae Guiart, 1935 (Cestoda: Trypanorhyncha), with a description of the adult of Pintneriella musculicola Yamaguti, 1934 and a redescription of P. gymnorhynchoides (Guiart, 1935) comb. n.

Ian Beveridge, Ronald A. Campbell

Folia Parasitologica 50[1] 61-71 (2003) | DOI: 10.14411/fp.2003.012

The family Rhopalothylacidae (Cestoda: Trypanorhyncha) is reviewed. The type species, Rhopalothylax gymnorhynchoides Guiart, 1935, is redescribed from the type specimens and belongs within the genus Pintneriella Yamaguti, 1934, previously described only from the plerocercus. Rhopalothylax therefore becomes a junior synonym of Pintneriella. The adult of Pintneriella musculicola Yamaguti, 1934 is described for the first time, from the shark Carcharias taurus Rafinesque from Australia. Pintneriella is characterised by two bothridia, a typical heteroacanthous armature, a unique, bipartite external seminal vesicle and a uterus deviated porally, terminating at a uterine pore. It belongs within the Heteracanthoidea but is distinguishable both from the Eutetrarhynchidae and the Gilquiniidae, the two families which it most closely resembles. Cladistic analyses align Pintneriella within the clade containing the families Gilquiniidae, Gymnorhynchidae and Molicolidae rather than with the Eutetrarhynchidae. The family Rhopalothylacidae is therefore retained provisionally to accommodate Pintneriella within the Heteracanthoidea. The second genus of the Rhopalothylacidae, Clujia Guiart, 1935, is unrecognisable from its description and cannot be redescribed from its holotype. It is therefore considered a genus inquirendum.

Obseravtions on the occurrence and maturation of Spinitectus inermis (Nematoda: Cystidicolidae) in the Sousa River, Portugal

Aurélia Saraiva, Anabela Pereira, Cristina Cruz

Folia Parasitologica 49[2] 167-168 (2002) | DOI: 10.14411/fp.2002.031

Electron microscopic study of a new microsporean Microsporidium epithelialis sp. n. infecting Tubifex sp. (Oligochaeta)

Mustapha Oumouna, Mansour El-Matbouli, Rudolf W. Hoffmann, Georges Bouix

Folia Parasitologica 47[4] 257-265 (2000) | DOI: 10.14411/fp.2000.044

The cytology of a new microsporean parasite Microsporidium epithelialis sp. n. from the intestinal epithelial cells of the freshwater oligochaete Tubifex sp. (Tubificidae) is described. The microsporean occurred together with an actinosporean of the genus Triactinomyxon, which was found between the epithelial cells. The merogonic and sporogonic stages (mature spores included) of the microsporean parasite are monokaryotic. An individual sporophorous vesicle surrounds each spore. The fixed and stained spore has an average dimension of 1.9-2.5 × 0.9-1.2 µm. The spores are oval with a characteristic surface layer, showing ornamentation-like projections, which are in close contact to the exospore. A short polar filament forming three to four coils traverses the polaroplast with two lamellar layers. The ultrastructure and other characteristic features of this microsporean parasite are distinct from those of the microsporean species described so far from oligochaetes.

Susceptibility of IFN-γ or IL-12 knock-out and SCID mice to infection with two microsporidian species, Encephalitozoon cuniculi and E. intestinalis

Jiří Salát, Bohumil Sak, Thuy Le, Jan Kopecký

Folia Parasitologica 51[4] 275-282 (2004)

Susceptibility of three strains of immunodeficient mice to two related microsporidian species Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923 and Encephalitozoon intestinalis (Cali, Kotler et Orenstein, 1993) was compared. While both, severe combined immunodeficient (SCID) and interferon-gamma knock-out (IFN-γ KO) mice, succumbed to either intraperitoneal (i.p.) or peroral (p.o.) (natural) infection with both parasites, only i.p. infection with E. cuniculi killed interleukin-12 knock-out (IL-12 KO) mice. IFN-γ KO mice died earlier than SCID mice. Adoptive transfer of naive splenocytes from IFN-γ KO mice did not protect the SCID mice from a lethal infection with either of the Encephalitozoon species. However, reconstituted mice survived significantly longer (P<0.05), thus indicating the role of IFN-γ produced by host NK cells in the development of mechanisms of anti-microsporidial protective immunity. Non-lethal outcome of the infection always correlated with the increase in CD8+ T lymphocyte subpopulation. Both E. intestinalis-infected IFN-γ KO and IL-12 KO mice produced comparable levels of specific antibodies, suggesting that antibodies did not protect IFN-γ KO mice from lethal infection.

Infections of Unicauda clavicauda (Kudo, 1934) (Myxozoa) in the skin of Notropis hudsonius (Cyprinidae) from Montana, with a synopsis of the genus Unicauda Davis, 1944

David K. Cone, Jason S. Melendy

Folia Parasitologica 47[4] 273-278 (2000) | DOI: 10.14411/fp.2000.047

Infections of Unicauda clavicauda (Kudo, 1920) Davis, 1944 (Myxozoa) are described from Notropis hudsonius (Clinton) in Montana. Plasmodia form beneath scales of the body and produced spores within a loosely-defined matrix. Fixed spores are oval in front view, 11-14 µm long and 9-10.5 µm wide, and contain a posterior appendage that is up to 26 µm long. The polar capsules are 4-6 µm long and 2.5-4 µm wide. The study represents the first report of U. clavicauda since the original species description and a new host and geographical record. The taxonomic history of Unicauda Davis, 1944 is summarised and it is concluded the following 10 species are valid members of the genus: U. aristichthydis Zhao et Ma, 1995, U. brachyura (Ward, 1919), U. caudatus (Gogebashvili, 1965), U. clavicauda, U. crassicauda (Kudo, 1934), U. lumae Rahemo, 1976, U. macrura (Gurley, 1893), U. magna Minchew, 1981, U. pelteobagrus Ma, 1998, and U. wuhanensis Xiao et Chen, 1993. All of these species have circular, subcircular, or oval spores in frontal view and all parasitise fish of the superorder Ostariophysi. As a group they are known from temperate freshwater locations in North America, Europe and Asia. A list of 16 species described or transferred to Unicauda at one time or another, but not recognised as members of the genus in the present study, is provided.

Chimaerula bonai sp. n. (Cestoda: Dilepididae) from the bare-faced ibis, Phimosus infuscatus (Lichtenstein) (Aves: Threskiornithidae) in Paraguay

Boyko B. Georgiev, Claude Vaucher

Folia Parasitologica 47[4] 303-308 (2000) | DOI: 10.14411/fp.2000.052

Chimaerula bonai sp. n. is described from the small intestine of Phimosus infuscatus (Lichtenstein) in Paraguay. The new species differs from the other two species of Chimaerula Bona, 1994, i.e., Chimaerula woodlandi (Prudhoe, 1960) and Chimaerula leonovi (Belogurov et Zueva, 1968), mainly by the intermediate number of rostellar hooks (30-34 compared to 42-46 in the former and 20-22 in the latter), longer rostellar hooks (31-34 µm versus 26 µm and 19-21 µm, respectively), shorter cirrus sac (58-82 µm versus 158-201 µm and 134-183 µm, respectively) and the absence of rosethorn spines in the cirrus armament. Modifications in the generic diagnosis of Chimaerula are proposed in order to conform it with some peculiarities of the new species (i.e., the relatively small and thin cirrus, the absence of rosethorn spines in its armament and the small cirrus sac).

Redescription of Proteocephalus bagri and P. rhamdiae (Cestoda: Proteocephalidae), parasites of Rhamdia quelen (Siluriformes: Pimelodidae) from South America, with comments on morphological variation

Alicia A. Gil de Pertierra

Folia Parasitologica 49[1] 55-66 (2002) | DOI: 10.14411/fp.2002.012

The pimelodid fish Rhamdia quelen (Quoy et Gaimard, 1824) in South America harbours two species of proteocephalid cestodes, Proteocephalus bagri Holcman-Spector et Mañé-Garzón, 1988 and P. rhamdiae Holcman-Spector et Mañé-Garzón, 1988. These species are redescribed based on a detailed morphological study, supported by multivariate analysis (principal component analysis). Features distinguishing these species are: (1) the shape of proglottides, (2) the mean number of testes, (3) the topography of vitelline follicles, (4) the thickness of internal longitudinal musculature, (5) the mean number of uterine branches, (6) the ratio of cirrus pouch length to proglottis width, (7) the shape of ovary in mature and gravid proglottides and (8) the genital pore position in mature proglottides. The specific status of P. bagri and P. rhamdiae is confirmed and neotypes of both species are designated.

Three species of Magnibursatus Naidenova, 1969 (Digenea: Derogenidae) from Atlantic and Black Sea marine teleosts

Aneta Kostadinova, Anne Marie Power, Mercedes Fernández, Juan Antonio Balbuena, Juan Antonio Raga, David I. Gibson

Folia Parasitologica 50[3] 202-210 (2003) | DOI: 10.14411/fp.2003.036

Three species of Magnibursatus Naidenova, 1969 are described from marine teleosts: M. skrjabini (Vlasenko, 1931), the type species of the genus, from the gobiid Zosterisessor ophiocephalus on the Bulgarian Black Sea coast; M. bartolii sp. n. from the sparid Boops boops off the Atlantic coast of Spain; and M. minutus sp. n. from the gobiid Neogobius eurycephalus on the Bulgarian Black Sea coast. M. bartolii differs from all other Magnibursatus species in its larger sinus-sac (length >250 µm, width >150 µm) and the more posterior location of testes. This species is also unusual in that it occurs in the branchial chamber and on the gills of its host. M. minutus is distinguished by the distinctly smaller dimensions of the body (length <1000 µm, width <200 µm), organs and eggs. These species are also distinguished from both M. caudofilamentosa (Reimer, 1971) and Tyrrhenia blennii Paggi et Orecchia, 1975. A key to the species of Magnibursatus is presented.

Infection prevalence, seasonality and host specificity of actinosporean types (Myxozoa) in an Atlantic salmon fish farm located in Northern Scotland

Ahmet Özer, Rodney Wootten, Andrew P. Shinn

Folia Parasitologica 49[4] 263-268 (2002) | DOI: 10.14411/fp.2002.050

A total of 28,387 oligochaetes belonging to the families Tubificidae, Lumbriculidae, Naididae and Enchytraeidae were examined at regular intervals for actinosporean infections from October 1996 to August 1998 from a freshwater salmon farm in Northern Scotland. A total of 21 types of actinosporeans belonging to seven collective groups synactinomyxon (three types), aurantiactinomyxon (four types), echinactinomyxon (five types), raabeia (six types), triactinomyxon (one type), neoactinomyxum (one type) and siedleckiella (one type) were found. Synactinomyxon type 1, echinactinomyxon type 1 and raabeia type 4 were most abundant. The overall infection prevalence of oligochaetes was 2.9%. Aurantiactinomyxon, synactinomyxon and neoactinomyxum were most common in summer and autumn. Raabeia was most common in spring and summer and echinactinomyxon in winter and spring. Siedleckiella was found only in spring and triactinomyxon in all seasons except winter. A positive relationship between water temperature and the number of actinosporean types released was observed. Most actinosporean types were found in only one host species.

Genotypic, phenotypic, biochemical, physiological and pathogenicity-based categorisation of Acanthamoeba strains

Naveed Ahmed Khan, Noor Khan Tareen

Folia Parasitologica 50[2] 97-104 (2003) | DOI: 10.14411/fp.2003.017

The genus Acanthamoeba includes more than 20 morphological species, but classification is problematical. Recently, the discovery of substantial interstrain differences in ribosomal DNA (rDNA) sequences has prompted questions about the relatedness of strains of the same species. In this study, therefore, we have investigated relationships between two isolates of A. polyphaga, CCAP 1501/3c and ATCC 30871, using morphological, biochemical, physiological, molecular and cytotoxicity assays. We observed that A. polyphaga ATCC 30871 exhibited up to six arms in endocyst while A. polyphaga CCAP 1501/3c exhibited a maximum of 5 arms thus indicating their position in group 2 and 3, respectively. Acanthamoeba polyphaga ATCC 30871 exhibited growth at 37°C and growth on 1M mannitol plates while A. polyphaga CCAP 1501/3c did not. In addition, both isolates exhibited differences in isoenzyme banding patterns and rDNA restriction fragment polymorphisms. More importantly, A. polyphaga ATCC 30871 produced cytotoxicity on corneal epithelial cells while A. polyphaga CCAP 1501/3c had no effects, suggesting differences in pathogenicity. Thus, all the results provide evidence for significant differences between the strains and further provided the basis for reclassification of the isolates. Implications of these results in the clinical diagnosis of pathogenic Acanthamoeba are discussed.

Ellipsomyxa gobii gen. et sp. n. (Myxozoa: Ceratomyxidae) in the common goby Pomatoschistus microps (Teleostei: Gobiidae) from Denmark

Marianne Køie

Folia Parasitologica 50[4] 269-271 (2003) | DOI: 10.14411/fp.2003.045

A new myxosporean species Ellipsomyxa gobii gen. et sp. n. is described from the common goby Pomatoschistus microps (Krøyer) (Perciformes, Gobiidae). Plasmodia with long branched pseudopodia in the gallbladder develop to subspherical bisporous plasmodia. The myxospores were found in the gallbladder, and the hepatic and bile ducts. The new genus is characterised by the morphology of the myxospores. The myxospores have smooth thin valves elongated in the direction perpendicular to the plane of the straight central transverse indistinct sutural line. The two spherical polar capsules open some distance from the sutural line on opposite sides. The new genus thereby differs from Leptotheca Thélohan, 1895. Ellipsomyxa gobii is tentatively placed in the Ceratomyxidae.

Effect of the salivary gland and midgut extracts from Ixodes ricinus and Dermacentor reticulatus (Acari: Ixodidae) on the growth of Borrelia garinii in vitro

Ivo Rudolf, Zdenek Hubálek

Folia Parasitologica 50[2] 159-160 (2003) | DOI: 10.14411/fp.2003.029

Ephemera strigata imagoes are the likely source of a parasitic nematode infection of fish

Riyo Hirasawa, Masahide Yuma

Folia Parasitologica 50[4] 313-314 (2003) | DOI: 10.14411/fp.2003.051

Pseudoallencotyla gen. n., a new genus for Allencotyla pricei (Kritsky, Noble et Moser, 1978) (Monogenea: Heteraxinidae), with a key to genera of Heteraxininae

Francisco E. Montero, F. Javier Aznar, Mercedes Fernández, Juan A. Raga

Folia Parasitologica 50[1] 43-47 (2003) | DOI: 10.14411/fp.2003.007

In this study, we clarify the taxonomic status of Allencotyla pricei based on a re-examination of paratypes and voucher specimens. Four important characters are added to previous descriptions: the vagina is ventral; the cirrus is absent; the eggs are fusiform and have two polar filaments (one about 3.5 times longer than the other); and, there are two flat sclerites at each side of the dorsal trident-shaped sclerite in the clamps. A comparison of A. pricei with species from all the genera of the Heteraxininae, including Allencotyla mcintoshi, indicates that A. pricei has several exclusive characters, i.e., a ventral vagina, vaginal armature, two additional dorsal sclerites in the clamps, a ventral mouth, and a question mark-shaped ovary. The combination of characters found in A. pricei is not shared with any other species within the Heteraxininae. In view of these features, A. pricei is assigned to a new genus, Pseudoallencotyla gen. n., as P. pricei comb. n.

Myxidium biliare sp. n. (Myxozoa) from gall bladder of Galaxias maculatus (Osmeriformes: Galaxiidae) in Patagonia (Argentina)

Gustavo P. Viozzi, Verónica R. Flores

Folia Parasitologica 50[3] 190-194 (2003) | DOI: 10.14411/fp.2003.034

Myxidium biliare sp. n., a new myxosporean species parasitizing the gall bladder of Galaxias maculatus (Jenyns), in Patagonia, is described. Its coelozoic plasmodia were floating free in the bile. Spores are fusiform 13.7 ± 0.9 µm long and 6.9 ± 0.6 µm wide, with rounded ends in frontal view and slightly pointed ends in sutural view; shell with ridges and sinuous sutural line. Both maximum prevalence and maximum percentage of immature plasmodia occurred in summer. In winter the prevalence and the percentage of immature plasmodia fell to their lowest values. Prevalence was independent of host sex but increased with host length. Prevalence in 15 Patagonian Andean lakes (situated from 39°25'S to 41°30'S) ranged between 4.2% and 70%.

Acolpenteron australe sp. n. (Dactylogyridae: Dactylogyrinae), a new species from the ureters of Percichthys trucha (Perciformes: Percichthyidae) in Patagonia (Argentina)

Gustavo P. Viozzi, Norma L. Brugni

Folia Parasitologica 50[2] 105-108 (2003) | DOI: 10.14411/fp.2003.018

Acolpenteron australe sp. n. (Dactylogyridae, Dactylogyrinae) is described from ureters and renal tubules of Percichthys trucha (Cuvier et Valenciennes) (Perciformes, Percichthyidae) from Andean Patagonian lakes. The new species has a haptor with 14 hooks, with shanks comprised of two subunits. It has overlapped intercaecal gonads, male copulatory organ as a sclerotized tube with one counterclockwise coil and a J-shaped accessory piece. It differs from the other species of Acolpenteron by having a non-forked accessory piece. This is the first monogenean species described from a percichthyid host in South America.

Annulotrematoides bryconi sp. n. (Monogenea: Dactylogyridae) parasitic on Brycon cephalus (Osteichthyes: Characidae) from Brazil

Ana Maria Cuglianna, Nelsonda Silva Cordeiro, José Luis Luque

Folia Parasitologica 50[4] 272-274 (2003) | DOI: 10.14411/fp.2003.046

Annulotrematoides bryconi sp. n. is described and illustrated from specimens collected from gills of characiform fish, Brycon cephalus (Günther, 1869), in pisciculture ponds from Pirassununga, São Paulo, Brazil. Diagnostic characters of the new species are the tegument of trunk showing annulations, except on the cephalic regiona, and copulatory complex comprising sclerotized male copulatory organ coiled in 11/2 rings. This is the first record of monogeneans parasitic on the gills of B. cephalus.

Gnathia pantherina sp. n. (Crustacea: Isopoda: Gnathiidae), a temporary ectoparasite of some elasmobranch species from southern Africa

Nico J. Smit, Linda Basson

Folia Parasitologica 49[2] 137-151 (2002) | DOI: 10.14411/fp.2002.025

Haematophagous larvae of a gnathiid isopod were collected from the gills, nares and buccal cavity of a single leopard catshark Poroderma pantherinum (Smith, 1838) at Jeffreys Bay and five puffadder shysharks Haploblepharus edwardsii (Voight, 1832) and one blackspotted electric ray Torpedo fuscomaculata Peters, 1855, at the De Hoop Nature Reserve on the South African south coast. Larvae were kept in fresh seawater until their moult into adult stages. The morphology of the adult males did not conform to that of any known species and they are therefore described as Gnathia pantherina sp. n. The descriptions of the adult male, female and praniza larva are based on light and scanning electron microscopy observations. Characteristic features of this species include the large size of all the final life-cycle stages, the deeply divided mediofrontal process of the male, the morphology of the pylopods and maxillipedes of the female, and the number of teeth on the mandibles (eight) and maxillules (seven) of the praniza larvae.

Three new species of the ectoparasitic mites of the genus Syringophiloidus Kethley, 1970 (Acari: Syringophilidae) from passeriform birds from Slovakia

Maciej Skoracki

Folia Parasitologica 49[4] 305-313 (2002) | DOI: 10.14411/fp.2002.057

Three new quill mite species of the genus Syringophiloidus Kethley, 1970 (Acari: Syringophilidae) from Slovakia are described and figured: S. bombycillae sp. n. from the waxwing Bombycilla garrulus (L.) (Passeriformes: Bombycillidae), S. schoeniclus sp. n. from the reed bunting Emberiza schoeniclus L. (Passeriformes: Emberizidae) and S. montanus sp. n. from the tree sparrow Passer montanus (L.) (Passeriformes: Ploceidae). A key to all known species of the genus Syringophiloidus is given.

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