Description of Lutziella swatensis sp. n (Trematoda: Dicrocoelidae) from Rattus rattus in Swat, Pakistan / Descrição de Lutziella swatensis sp. n (Trematoda: Dicrocoelidae) de Rattus rattus em Swat, Paquistão

A new species of the genus Lutziella (Rohde, 1966) Yamaguti, 1971 is described here and named Lutziella swatensis sp.nov. from the liver of rat (Rattus rattus L.). The new species is characterized by having body flat, smooth, longer than broad with maximum width at the level of the ovary, oral sucker with weak musculature, pharynx small; eosophagus long; caeca of irregular shape which bifurcate on the anterior border of the ovary in to unequal portions, acetabulum weakly muscular, post-testicular, testes lobed, cirrus pouch somewhat median, small in size containing winding seminal vesicle, prostatic complex and short ejaculatory duct. Genital pore median. Ovary post testicular, submedian; seminal receptacle overlapping ovary, laurer’s canal present. Vitellaria follicular extending on each side from almost the level of testes to anterior portion of posterior half of the body. Uterus filled with eggs occupying most of the body, eggs oval rather small, numerous, brownish in colour, excretory vesicle tubular with terminal pore. Lutziella swatensis n. sp. is the second species of the genus known from Pakistan as well as the second species described from murid rodents in the world.

Uma nova espécie do gênero Lutziella (Rohde, 1966) Yamaguti, 1971 é descrita aqui e denominada Lutziella swatensis sp.nov. do fígado do rato (Rattus rattus L.). A nova espécie é caracterizada por ter corpo liso, liso, mais longo que largo com largura máxima ao nível do ovário, otário oral com musculatura débil, faringe pequena; eosôfago longo; ceco de forma irregular que se bifurca na borda anterior do ovário em porções desiguais, acetábulo fracamente muscular, pós-testicular, testículos lobados, bolsa cirrus um pouco mediana, pequeno em tamanho contendo vesícula seminal sinuosa, complexo prostático e ducto ejaculatório curto. Mediana dos poros genitais. Ovário pós testicular, submediano; ovário sobreposto do receptáculo seminal, canal de laurer presente. Vitellaria folicular que se estende de cada lado de quase o nível dos testículos para a porção anterior da metade posterior do corpo. Útero cheio de ovos que ocupam a maior parte do corpo, oval ovos bastante pequenos, numerosos, de cor acastanhada, vesícula excretor tubular com poro terminal. Lutziella swatensis n. sp. é a segunda espécie do gênero conhecida do Paquistão, bem como a segunda espécie descrita de roedores do mundo.

Two new species of Unikaryon (Microsporidia) hyperparasitic in microphallid metacercariae (Digenea) from Florida intertidal crabs.

The genus Unikaryon (Microsporidia) holds exclusively hyperparasites of Platyhelminthes. Four species of Unikaryon are presently known from trematodes infecting mollusks and fish, and one from a cestode infecting a fish. Here we report two species of Unikaryon from microphallid trematode metacercariae parasitizing the brachyuran crabs, Panopeus herbstii and Pachygrapsus transversus, collected from intertidal habitats in Florida. The first microsporidium, which we assign here to a new species, Unikaryon panopei sp. n., was isolated from Microphallus sp. encysted in Panopeus herbstii from Tampa Bay. The specific designation for the second Unikaryon sp. (Unikaryon sp. 2), which occurred in metacercaria of Diacetabulum sp. found in P. transversus from the Florida Keys, is pending due to the lack of SSrDNA sequence data. Light and electron microscopy demonstrates that both species display characteristics of the genus Unikaryon including the arrangement of spores in sets of two, large posterior vacuole, and eccentric position of the polar filament. Spores of Unikaryon panopei sp. n., unlike those of Unikaryon sp. 2, assemble in large membrane-bound masses containing hundreds of organisms, and display a larger number of polar filament coils - 7-8, compared to 4-5 in Unikaryon sp. 2 The SSUrDNA-inferred phylogenetic analysis places Unikaryon panopei in one clade with Unikaryon legeri, the only other molecularly characterized member of the genus, with 94% of SSUrDNA similarity. These findings increase the number of species parasitizing trematodes and broaden the host range of Unikaryon spp.

Are Melanoides tuberculata and Tarebia granifera (Gastropoda, Thiaridae), suitable first intermediate hosts of Clonorchis sinensis in Vietnam?

BACKGROUND: Two thiarid snail species, Melanoides tuberculata and Tarebia granifera have been reported as first intermediate hosts of the liver fluke Clonorchis sinensis; however, their role as true first intermediate hosts has not been verified. Thus, the present study aimed to clarify the suitability of these two snail species as first intermediate hosts of C. sinensis. This was accomplished by collecting snails from a highly endemic area for C. sinensis in Vietnam, the Thac Ba reservoir, and identifying shed cercariae using molecular techniques. We also conducted experimental infections of five snail species including M. tuberculata and T. granifera with eggs of C. sinensis. METHODOLOGY/PRINCIPAL FINDINGS: A total of 11,985 snails, representing 10 species were sampled. Five snail species, M. tuberculata, T. granifera, Lymnaea swinhoei, Parafossarulus manchouricus, and Bithynia fuchsiana were found shedding cercariae with an overall prevalence of infection ranging from 0.7% to 11.5%. Seven cercarial types were recorded. Cercariae of C. sinensis were only found in Parafossarulus manchouricus. Using a multiplex PCR approach for detecting C. sinensis infection, the prevalence in P. manchouricus was 4.2%. Additionally, all five snail species were experimentally exposed to C. sinensis eggs, however only P. manchouricus was successfully infected with an infection rate of 7.87%. CONCLUSIONS/SIGNIFICANCE: We confirmed that in the Thac Ba reservoir, Vietnam, the two thiarids, M. tuberculata and T. granifera are not suitable first intermediate hosts of C. sinensis. Only P. manchouricus was found infected by C. sinensis in nature, and was the only species that became infected experimentally.

Following the infection dynamics of the tropical trematode Oligogonotylus mayae in its intermediate and definitive hosts for 13 years.

We present a time series of 13 years (2003-2016) of continuous monthly data on the prevalence and mean abundance of the trematode Oligogonotylus mayae for all the hosts involved in its life cycle. We aimed to determine whether annual (or longer than annual) environmental fluctuations affect these infection parameters of O. mayae in its intermediate snail host Pyrgophorus coronatus, and its second and definitive fish host Mayaheros urophthalmus from the Celestun tropical coastal lagoon, Yucatan, Mexico. Fourier time series analysis was used to identify infection peaks over time, and cross-correlation among environmental forcings and infection parameters. Our results suggest that the transmission of O. mayae in all its hosts was influenced by the annual patterns of temperature, salinity and rainfall. However, there was a biannual accumulation of metacercarial stages of O. mayae in M. urophthalmus, apparently associated with the temporal range of the El Niño-Southern Oscillation (five years) and the recovery of the trematode population after a devasting hurricane. Taking O. mayae as an example of what could be happening to other trematodes, it is becoming clear that environmental forcings acting at long-term temporal scales affect the population dynamics of these parasites.

Odds ratios and hurdle models: a long-term analysis of parasite infection patterns in endangered young-of-the-year suckers from Upper Klamath Lake, Oregon, USA.

We used odds ratios and a hurdle model to analyze parasite co-infections over 25 years on >20,000 young-of-the year of endangered Shortnose and Lost River Suckers. Host ecologies differed as did parasite infections. Shortnose Suckers were more likely to be caught inshore and 3-5 times more likely to have Bolbophorus spp. and Contracaecum sp. infections, and Lost River Suckers were more likely to be caught offshore and approximately three times more likely to have Lernaea cyprinacea infections. An observed peak shift seems likely to be due to a lower host size limit for Bolbophorus spp. (13.6 mm) compared with L. cyprinacea (23.4 mm). The large data set allowed us to generate strong hypotheses: (i) that a major marsh restoration project had unintended consequences that resulted in an increase in infections; (ii) that co-infection with Bolbophorus spp. increased the odds of infection by L. cyprinacea and Contracaecum sp.; (iii) that significant declines in the odds of infection over approximately 25 days were due to parasite-induced host mortality; (iv) that the fish's small size relative to L. cyprinacea and Contracaecum sp. might be directly lethal; (v) that the absence of L. cyprinacea infections in the early 1990s was associated with good year-class production of the suckers; and (vi) that parasites might increase the odds of vagrancy from the nursery ground.

Helminth-microbiota cross-talk - A journey through the vertebrate digestive system.

The gastrointestinal (GI) tract of vertebrates is inhabited by a vast array of organisms, i.e., the microbiota and macrobiota. The former is composed largely of commensal microorganisms, which play vital roles in host nutrition and maintenance of energy balance, in addition to supporting the development and function of the vertebrate immune system. By contrast, the macrobiota includes parasitic helminths, which are mostly considered detrimental to host health via a range of pathogenic effects that depend on parasite size, location in the GI tract, burden of infection, metabolic activity, and interactions with the host immune system. Sharing the same environment within the vertebrate host, the GI microbiota and parasitic helminths interact with each other, and the results of such interactions may impact, directly or indirectly, on host health and homeostasis. The complex relationships occurring between parasitic helminths and microbiota have long been neglected; however, recent studies point towards a role for these interactions in the overall pathophysiology of helminth disease, as well as in parasite-mediated suppression of inflammation. Whilst several discrepancies in qualitative and quantitative modifications in gut microbiota composition have been described based on host and helminth species under investigation, we argue that attention should be paid to the systems biology of the gut compartment under consideration, as variations in the abundances of the same population of bacteria inhabiting different niches of the GI tract may result in varying functional consequences for host physiology.

An improved genome assembly of the fluke Schistosoma japonicum.

BACKGROUND: Schistosoma japonicum is a parasitic flatworm that causes human schistosomiasis, which is a significant cause of morbidity in China and the Philippines. A single draft genome was available for S. japonicum, yet this assembly is very fragmented and only covers 90% of the genome, which make it difficult to be applied as a reference in functional genome analysis and genes discovery. FINDINGS: In this study, we present a high-quality assembly of the fluke S. japonicum genome by combining 20 G (~53X) long single molecule real time sequencing reads with 80 G (~ 213X) Illumina paired-end reads. This improved genome assembly is approximately 370.5 Mb, with contig and scaffold N50 length of 871.9 kb and 1.09 Mb, representing 142.4-fold and 6.2-fold improvement over the released WGS-based assembly, respectively. Additionally, our assembly captured 85.2% complete and 4.6% partial eukaryotic Benchmarking Universal Single-Copy Orthologs. Repetitive elements account for 46.80% of the genome, and 10,089 of the protein-coding genes were predicted from the improved genome, of which 96.5% have been functionally annotated. Lastly, using the improved assembly, we identified 20 significantly expanded gene families in S. japonicum, and those genes were primarily enriched in functions of proteolysis and protein glycosylation. CONCLUSIONS: Using the combination of PacBio and Illumina Sequencing technologies, we provided an improved high-quality genome of S. japonicum. This improved genome assembly, as well as the annotation, will be useful for the comparative genomics of the flukes and more importantly facilitate the molecular studies of this important parasite in the future.

Suppression of mRNAs encoding CD63 family tetraspanins from the carcinogenic liver fluke Opisthorchis viverrini results in distinct tegument phenotypes.

The liver fluke Opisthorchis viverrini infects 10 million people in Southeast Asia and causes cholangiocarcinoma (CCA). Fluke secreted and tegumental proteins contribute to the generation of a tumorigenic environment and are targets for drug and vaccine-based control measures. Herein, we identified two tetraspanins belonging to the CD63 family (Ov-TSP-2 and Ov-TSP-3) that are abundantly expressed in the tegument proteome of O. viverrini. Ov-tsp-2 and tsp-3 transcripts were detected in all developmental stages of O. viverrini. Protein fragments corresponding to the large extracellular loop (LEL) of each TSP were produced in recombinant form and antibodies were raised in rabbits. Ov-TSP-2 and TSP-3 were detected in whole worm extracts and excretory/secretory products of O. viverrini and reacted with sera from infected hamsters and humans. Antibodies confirmed localization of Ov-TSP-2 and TSP-3 to the adult fluke tegument. Using RNA interference, Ov-tsp-2 and tsp-3 mRNA expression was significantly suppressed for up to 21 days in vitro. Ultrastructural observation of tsp-2 and tsp-3 dsRNA-treated flukes resulted in phenotypes with increased tegument thickness, increased vacuolation (tsp-2) and reduced electron density (tsp-3). These studies confirm the importance of CD63 family tegument tetraspanins in parasitic flukes and support efforts to target these proteins for vaccine development.

Phylogeny and morphology of Ovipleistophora diplostomuri n. sp. (Microsporidia) with a unique dual-host tropism for bluegill sunfish and the digenean parasite Posthodiplostomum minimum (Strigeatida).

Microsporidia are diverse opportunistic parasites abundant in aquatic organisms with some species hyperparasitic in digenean parasites. In the current study, we describe a unique microsporidian parasite, Ovipleistophora diplostomuri n. sp. that has a tropism for both the bluegill sunfish Lepomis macrochirus, and its digenean parasite Posthodiplostomum minimum. Though the microsporidium first infects a fish, the subsequent infection causes hypertrophy of the metacercarial wall and degeneration of the P. minimum metacercariae within the fish tissue. Genetic analysis placed this species within Ovipleistophora and ultrastructural characteristics were consistent with the genus, including the presence of dimorphic spores within sporophorous vesicles. Meronts did not have a surface coat of dense material, which has been previously reported for the genus. This is the first Ovipleistophora species described that does not have a tropism for ovary. Genetics demonstrated that O. diplostomuri n. sp. groups closely within fish microsporidia and not other species known to be hyperparasitic in digeneans, suggesting that it evolved from fish-infecting microsporidians and developed a secondary tropism for a common and widespread digenean parasite. The high genetic identity to Ovipleistophora species demonstrates the close relationship of this unique microsporidian with other microsporidia that infect ovary.

DISCRIMINATION 28S RIBOSOMAL GENE OF TREMATODE CERCARIAE IN SNAILS FROM CHIANG MAI PROVINCE, THAILAND.

Trematode cercariae are commonly found in many freshwater gastropods. These cercariae can serve to identify the occurrence of such trematodes as Centrocestus formosanus, Haplorchis taichui, Haplorchoides sp, and Stellantchasmus falcatus, which are important parasites in Chiang Mai Province, Thailand. As the species of these cercariae cannot be identified accurately based on morphology, this study employed sequencing of a fragment of 28S ribosomal DNA and phylogenetic analysis to identify the trematode cercariae found in freshwater gastropods in Chiang Mai Province. Eight types of trematode cercariae were identified, namely, distome cercaria (grouped with Philophthalmus spp clade), echinostome cercaria (grouped with Echinostoma spp clade), furcocercous cercaria (grouped with Posthodiplostomum sp/Alaria taxideae/Hysteromorpha triloba clade), monostome cercaria (grouped with Catatropis indicus clade), parapleurolophocercous cercaria (grouped with Haplorchoides sp clade), pleurolophocercous cercaria (grouped with Centrocestusformosanus clade), transversotrema cercaria (grouped with Transversotrema spp clade), and xiphidiocercaria (grouped with Prosthodendrium spp clade). These results provide important information that can be used for identifying these parasites in epidemiological surveys.

Anatomopathological findings in captive-raised redwinged tinamou (Rhynchotus rufescens) / Achados anatomopatológicos em perdizes (Rhynchotus rufescens) criadas em cativeiro

The red-winged tinamou (Rhynchotus rufescens), a bird from the Tinamidae family, can be easily adapted to captivity. It is considered suitable for producing good quality meat while presenting great feed conversion rate, characteristics that make it interesting for commercial production. Therefore, in order to determine the major diseases that affect these birds, 114 birds from two different aviary types that died over a 12-year period, 1994-2006, were analyzed macro- and microscopically. Anatomical and pathological examinations showed that the most frequently affected systems were the urinary and digestive tracts. In the urinary tract, the main finding was gout, followed by amyloidosis and parasitism by the trematode Paratanaisia confusa. In the digestive tract, the presence of foreign material and parasitism by Capillaria penidoi were observed in the esophagus and crop. This study aims to describe the main anatomical and pathological findings in captive-bred red-winged tinamou and correlate them with the aviary type.(AU)

A perdiz (Rhynchotus rufescens) membro da família Tinamidae é uma ave que apresenta relativa facilidade à adaptação ao cativeiro. É considerada apta à produção de carne de boa qualidade, com ótima conversão alimentar. Essas características a torna interessante para produção comercial. Visando conhecer as principais afecções que acometem essas aves, foram analisados achados macro e microscópicos de 114 perdizes que vieram a óbito ao longo de 12 anos, entre 1994 e 2006 provenientes de criatório experimental, mantidas em dois diferentes tipos de recintos. Os exames anatomopatológicos revelaram que os sistemas mais acometidos foram o urinário e o digestório. No primeiro, a gota úrica foi o principal achado, seguida da amiloidose e parasitismo pelo trematoda Paratanaisia confusa. No sistema digestório, foi observada a presença de corpo estranho e parasitismo por Capillaria penidoi em esôfago e inglúvio. As aves mantidas em alojamento com piso natural apresentaram maior parasitismo, enquanto as que foram mantidas em recinto com piso de concreto e palha apresentaram maior quantidade de corpos estranhos no sistema gastrointestinal, caquexia e amiloidose. O objetivo deste trabalho foi descrever os principais achados anatomopatológicos em perdizes criadas em cativeiro, correlacionando-os com o tipo de recinto adotado.(AU)

Pathological and parasitological aspects of the peacock (Pavo cristatus) infection by Tanaisia (Paratanaisia) bragai / Aspectos patológicos e parasitológicos da infecção por Tanaisia (Paratanaisia) bragai em pavões (Pavo cristatus)

Trematodes belonging to the family Eucotylidae, including Tanaisia (Paratanaisia)bragai Santos, 1934are parasites of the kidney and ureter that affect several species of domestic and wild birds. Tanaisia bragai is considered a low pathogenic parasite, but high worm burdens may determine clinical complications, including signs of apathy, weight loss, diarrhea and death...

Os trematódeos da família Eucotylidae, incluindo Tanaisia (Paratanaisia)bragai Santos, 1934, são parasitos de rins e ureteres de várias espécies de aves domésticas e silvestres. Tanaisia bragai é considerada uma espécie pouco patogênica, mas que pode determinar complicações clínicas como apatia, perda de peso, diarreia e morte, quando em cargas parasitárias elevadas...

Parasitism by Paratanaisia bragai (Digenea, Eucotylidae) in commom waxbill (Estrilda astrild) / Parasitismo por Paratanaisia bragai em bico-de-lacre (Estrilda astrild)

O trematodeo digenético Paratanaisia bragai é descrito como parasito dos túbulos coletores renais e ureteres de aves. Esse helminto é usualmente pouco patogênico para a maioria dos hospedeiros; porém, em altas cargas parasitárias e em animais mais suscetíveis, pode causar sérios danos que resultam em apatia, perda de peso, desidratação e até mesmo a morte. O presente trabalho objetivou relatar pela primeira vez o trematoide P. bragai parasitando os rins de um passeriforme da espécie Estrilda astrild, conhecido popularmente como bico-de-lacre, de distribuição cosmopolita. A partir da análise histopatológica dos rins da ave, observou-se a presença dos vermes adultos e de ovos, grande dilatação dos ductos coletores renais, destruição e achatamento das células epiteliais de revestimento e, ao redor dos parasitos, observou-se moderada reação inflamatória. Os autores sugerem que a infecção pode ter sido acidental, uma vez que os moluscos terrestres que servem de hospedeiros intermediários para P. bragai não fazem parte da dieta natural descrita para os bico-de-lacre. Os resultados encontrados no presente estudo confirmaram um bico-de-lacre como possível hospedeiro de P. bragai, acrescentando essa espécie de ave e possivelmente todo o grupo dos passeriformes na epidemiologia da infecção por esse trematoide.(AU)

Increased parasitism of limpets by a trematode metacercaria in fisheries management areas of central Chile: effects on host growth and reproduction : management areas and parasitism.

The rapid increase in body size and abundance of most species inside Management and Exploitations Areas for Benthic Resources (MEABRs) has led to the proposal of these areas as a good complement for achieving the conservation objectives of Marine Protected Areas (MPAs). However, when evaluating MEABRs and MPAs as conservation and/or management tools, their impact upon parasite populations has rarely been considered, despite the fact that epidemiological theory suggests an increased susceptibility to parasitism under high population abundance. We evaluated the effects of MEABRs on the parasite abundance of Proctoeces lintoni and its impact on the growth of the host limpet Fissurella crassa in central Chile. Parasitic magnitude was higher inside MEABRs than in Open-Access Areas, and parasitized limpets showed a greater shell length, muscular foot biomass, and gonadosomatic index compared to non-parasitized limpets of the same age. Our results suggest that the life cycle of P. lintoni and, consequently, its trophic links have been strengthened inside MEABRs. The increased growth rate could reduce the time required to reach the minimum catch size and increase the reproductive and muscular output of the host population. Thus, parasitism should be considered in the conservation and management of economically important mollusk hosts.

Revisão taxonômica e elaboração de mapas de distribuição geográfica de espécies brasileiras da família Lymnaeidae Rafinesque, 1815 (Gastropoda, Basommatophora)

Moluscos da família Lymnaeidae Rafinesque, 1815, atuam como hospedeiros intermediários do trematódeo Fasciola hepatica Linnaeus, 1758, agente etiológico da fasciolose, doença parasitária de importância médica e veterinária. As áreas mais críticas onde a doença representa um problema de saúde pública estão localizadas nos países Andinos (Bolívia, Peru, Chile, Equador), região do Caribe (Cuba), norte da África (Egito) e Europa ocidental (Portugal, França e Espanha). Estima-se que mais de 20 milhões de pessoas encontram-se infectadas em todo o mundo. A variabilidade na morfologia da concha e a uniformidade na anatomia interna são características de vários gêneros e espécies da família as quais dificultam a determinação específica. Os objetivos do presente trabalho foram: 1) Analisar a morfologia de espécimes tipo outopótipos das espécies Galba viatrix d'Orbigny, 1835, G. truncatula (Müller, 1774), G.cubensis Pfeiffer, 1839, Lymnaea rupestris Paraense, 1982 e Pseudosuccinea columella(Say, 1817) e compará-las com limneídeos procedentes do Brasil; 2) Elucidar alocalidade tipo de P. columella; 3) Refinar e definir novos caracteres morfológicos que possam ser utilizados na identificação; 4) Rever e retificar a taxonomia dos limneídeos do acervo da coleção Fiocruz-CMM; 5) Elaborar mapas de distribuição geográfica dos limneídeos brasileiros.

Através das análises dos topótipos e de exemplares coletados no Brasil foram confirmadas a presença de G. viatrix, G. truncatula, G. cubensis e P.columella. Um neótipo é proposto para P. columella, considerando o desconhecimento da localidade tipo e a invalidade da série tipo para essa espécie. As diferenças evidenciadas entre as espécies de limneídeos foram encontradas principalmente na concha (microescultura e formato), sistema digestivo (estômago e glândulas salivares) e sistema reprodutor (oviduto, próstata, complexo peniano, vesicular seminal e ovotestis). Após avaliação e retificação, o acervo Fiocruz-CMM ficou composto por sete espécies em um total de 98 pontos de coleta, sendo 64 (65.3%) identificados com exemplares da espécie P. columella, 14 (14.3%) com G. truncatula, oito (8.2%) com G. cubensis, sete(7.1%) com G. viatrix, dois (2%) com L. diaphana King, 1830, dois (2%) com L. peregra (Müller, 1774) e um (1%) com L. stagnalis (Linnaeus, 1758). Após o levantamento da ocorrência das espécies no Brasil registrou-se: P. columella em 400 municípios (95,7%), G. viatrix em 10 (2,4%), G. cubensis em seis (1,4%), G. truncatulaem três (0,7%) e L. rupestris em um (0,2%). Pela primeira vez, foi elaborado mapas de distribuição de limneídeos no Brasil.

Revisão taxonômica e elaboração de mapas de distribuição geográfica de espécies brasileiras da família Lymnaeidae Rafinesque, 1815 (Gastropoda, Basommatophora) / Taxonomic revision and preparation of distribution maps geographic Brazilian species of Lymnaeidae family Rafinesque, 1815 (Gastropoda, Basommatophora)

Moluscos da família Lymnaeidae Rafinesque, 1815, atuam como hospedeiros intermediários do trematódeo Fasciola hepatica Linnaeus, 1758, agente etiológico da fasciolose, doença parasitária de importância médica e veterinária. As áreas mais críticas onde a doença representa um problema de saúde pública estão localizadas nos países Andinos (Bolívia, Peru, Chile, Equador), região do Caribe (Cuba), norte da África (Egito) e Europa ocidental (Portugal, França e Espanha). Estima-se que mais de 20 milhões de pessoas encontram-se infectadas em todo o mundo. A variabilidade na morfologia da concha e a uniformidade na anatomia interna são características de vários gêneros e espécies da família as quais dificultam a determinação específica. Os objetivos do presente trabalho foram: 1) Analisar a morfologia de espécimes tipo outopótipos das espécies Galba viatrix d'Orbigny, 1835, G. truncatula (Müller, 1774), G.cubensis Pfeiffer, 1839, Lymnaea rupestris Paraense, 1982 e Pseudosuccinea columella(Say, 1817) e compará-las com limneídeos procedentes do Brasil; 2) Elucidar alocalidade tipo de P. columella; 3) Refinar e definir novos caracteres morfológicos que possam ser utilizados na identificação; 4) Rever e retificar a taxonomia dos limneídeos do acervo da coleção Fiocruz-CMM; 5) Elaborar mapas de distribuição geográfica dos limneídeos brasileiros...

Através das análises dos topótipos e de exemplares coletados no Brasil foram confirmadas a presença de G. viatrix, G. truncatula, G. cubensis e P.columella. Um neótipo é proposto para P. columella, considerando o desconhecimento da localidade tipo e a invalidade da série tipo para essa espécie. As diferenças evidenciadas entre as espécies de limneídeos foram encontradas principalmente na concha (microescultura e formato), sistema digestivo (estômago e glândulas salivares) e sistema reprodutor (oviduto, próstata, complexo peniano, vesicular seminal e ovotestis). Após avaliação e retificação, o acervo Fiocruz-CMM ficou composto por sete espécies em um total de 98 pontos de coleta, sendo 64 (65.3%) identificados com exemplares da espécie P. columella, 14 (14.3%) com G. truncatula, oito (8.2%) com G. cubensis, sete(7.1%) com G. viatrix, dois (2%) com L. diaphana King, 1830, dois (2%) com L. peregra (Müller, 1774) e um (1%) com L. stagnalis (Linnaeus, 1758). Após o levantamento da ocorrência das espécies no Brasil registrou-se: P. columella em 400 municípios (95,7%), G. viatrix em 10 (2,4%), G. cubensis em seis (1,4%), G. truncatulaem três (0,7%) e L. rupestris em um (0,2%). Pela primeira vez, foi elaborado mapas de distribuição de limneídeos no Brasil...

Spatio-temporal variation in the prevalence of trematodes in the bivalve Perumytilus purpuratus.

Perumytilus purpuratus is an abundant bivalve located in the intertidal rocky zone of South America that has been considered as a key species of the ecosystem. There are few studies of the host-parasite relationship of this bivalve; thus, this research aims to analyse the spatial and temporal variation in the prevalence of trematodes in P. purpuratus. Bivalves were collected from three localities (El Tabo, Las Cruces and Montemar) of central Chile (33°S, 71°W) during different seasons of 2010. The bivalves were also collected every metre, from the lowest to the highest level of the intertidal rocky zone, to determine the parasite distribution within the localities. Three species of trematodes as sporocyst stages were found: Prosorhynchoides carvajali, Proctoeces sp. and an undetermined fellodistomid species. Of the 37,692 bivalve specimens collected, 2.68% were parasitised. The undetermined fellodistomid species was the most prevalent parasite observed (1.69%). There were little detected differences in the prevalence of some trematode species between seasons. The prevalence of P. carvajali varied between localities, being most prevalent at Montemar. The distribution of trematodes along the rocky zone within the localities was variable, with P. carvajali being more prevalent in the mid-lowest level of the intertidal zone and the undetermined fellodistomid species being more prevalent in the mid-highest level. Both the abundance of definitive hosts and the environmental conditions likely result in different levels of infection by trematodes in P. purpuratus between and within the localities.

Monogenoidean parasites of the gill lamellae of the sheepshead Archosargus probatocephalus (Walbaum) (Perciformes: Sparidae) from the Indian River Lagoon, Florida, with descriptions of four new species of Euryhaliotrema Kritsky & Boeger, 2002 (Dactylogyridae).

Examination of the gill lamellae of three sheepshead Archosargus probatocephalus (Walbaum) from the Indian River Lagoon in Florida revealed six species of Monogenoidea: Microcotyle archosargi MacCallum, 1913 (Microcotylidae); Neobenedenia sp. (Capsalidae); and four new species of Euryhaliotrema Kritsky & Boeger, 2002 (Dactylogyridae). The prevalence of all helminths was 100%, except for Neobenedenia sp., which was represented by a single immature specimen. The four new species, Euryhaliotrema carbuncularium n. sp., E. dunlapae n. sp., E. amydrum n. sp. and E. spirulum n. sp., are described and with E. carbunculus (Hargis, 1955) Kritsky & Boeger, 2002 apparently constitute a monophyletic clade of Euryhaliotrema spp. that parasitise sparid hosts in the western hemisphere. The Indian River Lagoon in Florida represents a new locality record for M. archosargi, and the sheepshead is apparently a new host record for a member (Neobenedenia sp.) of the Capsalidae.

Checklist of helminths from lizards and amphisbaenians (Reptilia, Squamata) of south America: [review]

A comprehensive and up to date summary of the literature on the helminth parasites of lizards and amphisbaenians from South America is herein presented. One-hundred eighteen lizard species from twelve countries were reported in the literature harboring a total of 155 helminth species, being none acanthocephalans, 15 cestodes, 20 trematodes and 111 nematodes. Of these, one record was from Chile and French Guiana, three from Colombia, three from Uruguay, eight from Bolivia, nine from Surinam, 13 from Paraguay, 12 from Venezuela, 27 from Ecuador, 17 from Argentina, 39 from Peru and 103 from Brazil. The present list provides host, geographical distribution (with the respective biome, when possible), site of infection and references from the parasites. A systematic parasite-host list is also provided.

Life cycle of Culuwiya tilapiae (Nasir y Gómez, 1976) (trematoda: haploporidae) in Venezuela

The life cycle of Culuwiya tilapiae (Nasir y Gómez, 1976) Overstreet and Curran, 2005, a digenean belonging to the family Haploporidae Nicoll, 1914 is redescibed and illustrated. The parasite infects naturally the snail, Pyrgophorus cf. spiralis (Guppy 1864), and the definitive host, Oreochromis mossambicus (Peters, 1852). Both molluscs and fish were collected from the Parque Litoral Laguna de los Patos, Cumaná, Estado Sucre, Venezuela. The cercariae were developed in redia in the digestive gland of molluscs and encysted on the water surface and more frequently on the bottom and walls of dishes. The 2-4 days old cysts of C. tilapiae were fed to laboratory reared O. mossambicus, and the trematode reaches sexual maturity in 22-32 days after the experimental infection. All developmental stages of C. tilapiae are described and illustrated. This species was compared with other members of Culuwiya and with Saccocoelioides tarpazensis Díaz and Gonzalez, 1990, for being the only recorded haploporids species in Venezuela and its life cycle had been elucidated and for the similarity with C. tilapiae. This species is redescribed herein represents the first record of Culuwiya Overstreet and Curran, 2005 in Venezuela.

El ciclo de vida de Culuwiya tilapiae (Nasir y Gómez, 1976) Overstreet y Curran, 2005, un digéneo perteneciente a la familia Haploporidae Nicoll, 1914 fue dilucidado. El parásito infecta naturalmente al caracol, Pyrgophorus cf. spiralis (Guppy, 1864), y al hospedador definitivo, Oreochromis mossambicus (Peters, 1852). Ambos, moluscos y peces fueron recolectados en el Parque Litoral Laguna de los Patos, Cumaná, estado Sucre, Venezuela. Las cercarias fueron desarrolladas en redias en la glándula digestiva del molusco, y enquista en la superficie del agua y más frecuente en el fondo y paredes del recipiente. Los quistes de 2-4 días de edad de C. tilapiae fueron suministrados a O. mossambicus nacidos en el laboratorio, y los tremátodos alcanzan su madurez sexual en 22-32 días después de la infección. Todos los estadios de desarrollo de C. tilapiae fueron descritos e ilustrados. Esta especie fue comparada con los miembros del género Culuwiya y con Saccocoelioides tarpazensis Díaz y González, 1990, por ser la única especie de haploporido en Venezuela, cuyo ciclo de vida ha sido dilucidado y por su similitud con C. tilapiae. Esta especie redescrita aquí, representa la primera vez que se registra el género en Venezuela.