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Florencia Cremonte - One of the best experts on this subject based on the ideXlab platform.
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a histopathological survey of the Razor Clam ensis macha pharidae along the patagonian argentina coast
Journal of Invertebrate Pathology, 2013Co-Authors: Nuria Vazquez, Federico Marquez, Silvina Van Der Molen, Elizabeth Perez Bruno, Carmen Mariangel Gilardoni, Florencia CremonteAbstract:Abstract This is the first study performed to determine the health status of the Razor Clam, Ensis macha, including six different populations along Argentina Patagonian coast and one of Chile. The parasites and pathologies affecting E. macha were analyzed and their prevalence and mean intensity values were calculated. To establish which factors affect the presence and intensity of infection, Generalized Linear Models (GLMs) were applied. Basophilic inclusions, ciliates, coccidians protozoans and turbellarians were found. We report an Aporocotylidae digenean and hemocyte infiltrations. None of the parasites is OIE (World Organisation for Animal Health) notifiable, and none seemed to be pathogenic, with the exception of the digenean. The prevalence of the parasites was affected mainly by environmental factors (such as site of sampling and season) instead of intrinsic conditions of the Clam (such as size, condition index, sex and gonadal stage). On the other hand, the maximum intensity of parasites was not only related with cold seasons but also with the partially spawned gonadal stage of E. macha. During this stage, the Clams would need to store energy for the next gametogenesis cycle, might be more susceptible to infection by the parasites.
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infection by gymnophallid metacercariae enhances predation mortality of sw atlantic stout Razor Clam tagelus plebeius
Journal of Sea Research, 2010Co-Authors: Mariana Addino, Florencia Cremonte, Betina J Lomovasky, Oscar IribarneAbstract:Abstract Parasite life cycles are frequently completed in different hosts, thus the parasites have its life cycle overlapped to natural trophic webs. The family Gymnophallidae (Class: Trematoda; Subclass: Digenea) includes digenetic parasites whose larval stages occur on bivalves and may affect bivalve predation by the final host of these parasites. In this work we evaluated: (a) if individuals of the Razor Clam Tagelus plebeius with higher parasite intensity suffer higher predation by the oystercatcher Haematopus palliatus and, (b) if there is any effect of parasite intensity on burrowing and escape behaviours of these Razor Clams which may enhance exposure to predators. Field experiments (oystercatcher exclusion vs. open access) showed that Clams with higher parasite intensity support higher predation by oystercatchers, which suggests a higher consumption of more parasitized Clams and thus, a more successful reproduction of parasites linked to the intensity of infection. However, Clam burrowing and escape behaviours did not show differences related to different parasite intensity, suggesting that the commonly believed mechanisms are not responsible in this case.
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presence and histopathological effects of the parvatrema sp digenea gymnophallidae in the stout Razor Clam tagelus plebeius bivalvia psammobiidae
Journal of Invertebrate Pathology, 2009Co-Authors: Patricia Mirella Da Silva, Florencia Cremonte, Rachel Costa Sabry, Rafael Diego Rosa, Liege Cantelli, M A BarraccoAbstract:The stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae) has a wide geographic distribution range, including the Brazilian coasts from the northeast (Alagoas) to the south (Santa Catarina). In March 2008, an episode of mass T. plebeius mortality (70%) occurred in an intertidal bed at The Pontal da Daniela, State of Santa Catarina, Brazil. We report here high prevalences (to 100%) of the trematode parasite Parvatrema sp. Cable, 1953 (Digenea, Gymnophallidae) infecting T. plebeius at high intensities. We describe the gymnophalid, echinostomatid and unidentified metacercariae parasites infecting the Clam and the host reactions elicited by them. The use of special diagnostic techniques such as Ray’s fluid thioglycollate medium (RFTM) and PCR assays to detect Perkinsus sp. pathogens, hemolymph cytology, and histopathological examinations did not show Perkinsus sp. infections, microcell infections, or neoplastic conditions. However, neither infections or pathology caused by trematode parasites; nor any other pathological condition could be uniquely correlated with the mortality event. A coincident flash flood might have contributed to cause the mortality episode. This is the first report of the Parvatrema sp. metacercariae larvae infecting the stout Razor Clam T. plebeius from Brazil.
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Presence and histopathological effects of the Parvatrema sp. (Digenea, Gymnophallidae) in the stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae)
Journal of Invertebrate Pathology, 2009Co-Authors: Patricia Mirella Da Silva, Florencia Cremonte, Rachel Costa Sabry, Rafael Diego Rosa, Liege Cantelli, M A BarraccoAbstract:The stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae) has a wide geographic distribution range, including the Brazilian coasts from the northeast (Alagoas) to the south (Santa Catarina). In March 2008, an episode of mass T. plebeius mortality (70%) occurred in an intertidal bed at The Pontal da Daniela, State of Santa Catarina, Brazil. We report here high prevalences (to 100%) of the trematode parasite Parvatrema sp. Cable, 1953 (Digenea, Gymnophallidae) infecting T. plebeius at high intensities. We describe the gymnophalid, echinostomatid and unidentified metacercariae parasites infecting the Clam and the host reactions elicited by them. The use of special diagnostic techniques such as Ray's fluid thioglycollate medium (RFTM) and PCR assays to detect Perkinsus sp. pathogens, hemolymph cytology, and histopathological examinations did not show Perkinsus sp. infections, microcell infections, or neoplastic conditions. However, neither infections or pathology caused by trematode parasites; nor any other pathological condition could be uniquely correlated with the mortality event. A coincident flash flood might have contributed to cause the mortality episode. This is the first report of the Parvatrema sp. metacercariae larvae infecting the stout Razor Clam T. plebeius from Brazil. © 2009 Elsevier Inc. All rights reserved.
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parasites of the stout Razor Clam tagelus plebeius psammobiidae from the southwestern atlantic ocean
Journal of Shellfish Research, 2006Co-Authors: Nuria Vazquez, Cristian Ituarte, Graciela Teresa Navone, Florencia CremonteAbstract:Abstract This work describes the parasites and their respective pathologies in the stout Razor Clam, Tagelus plebeius (Lightfoot, 1786) (Psammobiidae) from Argentinean coasts. It represents the first report about a histopathological survey for these species in the Southwestern Atlantic. Specimens of T. plebeius were collected at Mar Chiquita coastal lagoon (37°46′S, 57°27′W) (n = 104 dissected under stereomicroscope, n = 28 histologically sectioned and microscopically examined) and from the mouth of the Quequen Salado River (38°56′S, 60°33′W) (n = 14 dissected under stereomicroscope). Tagelus plebeius was found housing two ciliate species without apparent host reaction and acting as first intermediate host for two digenetic trematode species of the families Fellodistomidae and Gymnophallidae, by hosting sporocysts (mainly in gonad and digestive gland that results in the replacement of host tissues) and as second intermediate host by housing a gymnophallid metacercaria. Likewise, T. plebeius was found para...
M A Barracco - One of the best experts on this subject based on the ideXlab platform.
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presence and histopathological effects of the parvatrema sp digenea gymnophallidae in the stout Razor Clam tagelus plebeius bivalvia psammobiidae
Journal of Invertebrate Pathology, 2009Co-Authors: Patricia Mirella Da Silva, Florencia Cremonte, Rachel Costa Sabry, Rafael Diego Rosa, Liege Cantelli, M A BarraccoAbstract:The stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae) has a wide geographic distribution range, including the Brazilian coasts from the northeast (Alagoas) to the south (Santa Catarina). In March 2008, an episode of mass T. plebeius mortality (70%) occurred in an intertidal bed at The Pontal da Daniela, State of Santa Catarina, Brazil. We report here high prevalences (to 100%) of the trematode parasite Parvatrema sp. Cable, 1953 (Digenea, Gymnophallidae) infecting T. plebeius at high intensities. We describe the gymnophalid, echinostomatid and unidentified metacercariae parasites infecting the Clam and the host reactions elicited by them. The use of special diagnostic techniques such as Ray’s fluid thioglycollate medium (RFTM) and PCR assays to detect Perkinsus sp. pathogens, hemolymph cytology, and histopathological examinations did not show Perkinsus sp. infections, microcell infections, or neoplastic conditions. However, neither infections or pathology caused by trematode parasites; nor any other pathological condition could be uniquely correlated with the mortality event. A coincident flash flood might have contributed to cause the mortality episode. This is the first report of the Parvatrema sp. metacercariae larvae infecting the stout Razor Clam T. plebeius from Brazil.
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Presence and histopathological effects of the Parvatrema sp. (Digenea, Gymnophallidae) in the stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae)
Journal of Invertebrate Pathology, 2009Co-Authors: Patricia Mirella Da Silva, Florencia Cremonte, Rachel Costa Sabry, Rafael Diego Rosa, Liege Cantelli, M A BarraccoAbstract:The stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae) has a wide geographic distribution range, including the Brazilian coasts from the northeast (Alagoas) to the south (Santa Catarina). In March 2008, an episode of mass T. plebeius mortality (70%) occurred in an intertidal bed at The Pontal da Daniela, State of Santa Catarina, Brazil. We report here high prevalences (to 100%) of the trematode parasite Parvatrema sp. Cable, 1953 (Digenea, Gymnophallidae) infecting T. plebeius at high intensities. We describe the gymnophalid, echinostomatid and unidentified metacercariae parasites infecting the Clam and the host reactions elicited by them. The use of special diagnostic techniques such as Ray's fluid thioglycollate medium (RFTM) and PCR assays to detect Perkinsus sp. pathogens, hemolymph cytology, and histopathological examinations did not show Perkinsus sp. infections, microcell infections, or neoplastic conditions. However, neither infections or pathology caused by trematode parasites; nor any other pathological condition could be uniquely correlated with the mortality event. A coincident flash flood might have contributed to cause the mortality episode. This is the first report of the Parvatrema sp. metacercariae larvae infecting the stout Razor Clam T. plebeius from Brazil. © 2009 Elsevier Inc. All rights reserved.
Jiale Li - One of the best experts on this subject based on the ideXlab platform.
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a four crd c type lectin from Razor Clam sinonovacula constricta mediates agglutination and phagocytosis
Gene, 2020Co-Authors: Zhi Li, Maoxiao Peng, Yan Li, Jiale LiAbstract:Abstract C-type lectins are a superfamily of Ca2+-dependent carbohydrate-binding proteins that play crucial roles in invertebrate immunity. In this study, a novel C-type lectin gene (ScCTL-1) was identified in Razor Clam Sinonovacula constricta. The ScCTL-1 gene, consisting of four C-type carbohydrate recognition domains (CRDs) with an N-terminal signal peptide and a C-terminal transmembrane region. The gene is widely expressed in almost all tissues, with the highest expression in the hepatopancreas. To explore the functional characteristics of this structurally novel gene, tests of binding specificity, agglutinating activity, and phagocytic promoting activity were included in this study. Bacterial stimulation up-regulated ScCTL-1 expression in hemocytes. The binding activity of rScCTL-1 to bacteria was tested in vitro, and bacterial agglutination was observed under the same conditions. Ca2+ was essential for carbohydrate binding. Additionally, rScCTL-1 promoted the phagocytic activity of hemocytes to varying degrees against different bacteria, unlike the classical opsonin. These results suggest ScCTL-1 is a classical immune-related C-type lectin possessing unique immune-related properties.
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polymorphisms in the foxo gene are associated with growth traits in the sanmen breeding population of the Razor Clam sinonovacula constricta
Aquaculture and Fisheries, 2018Co-Authors: Zhiguo Dong, Jiale LiAbstract:Abstract We identified the FOXO gene and five single-nucleotide polymorphisms (SNPs) in its coding region in the Sanmen breeding population of the Razor Clam Sinonovacula constricta . The ScFOXO gene encodes a protein of 625 amino acids in length that contains a conserved DNA-binding domain. Real-time polymerase chain reaction analysis showed that ScFOXO mRNA is widely expressed in adult tissues, with higher expression in the siphons and gills. Of the SNPs, c.879G > C (Val293Val) and c.1725A > G (Ser575Ser) are synonymous mutations, and c.543C > T (Phe181Leu), c.848A > G (Tyr283Cys), and c.1625G > C (Gly542Phe) are non-synonymous mutations. The SNPs all show significant associations with total body weight, shell length, shell width, and shell height (SH) in this population. Polymorphic parameter analysis showed that all SNPs except c.848A > G (Tyr283Cys) exhibit complete linkage. The SNP c.1625G > C (Gly542Phe) was used for genetic linkage mapping and demonstrates the strongest linkage (logarithm of the odds [LOD] value: 41.46) with the marker 96616 (37.02 cM) in the linkage group 9. The LOD value of this marker in relation to growth traits ranges from 1.04 to 1.53; only markers with a LOD value ≥ 3 were considered to be linked with growth traits in the Razor Clam linkage map. In summary, ScFOXO may be a growth trait-related gene and may represent a marker for Sanmen breeding group selection.
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complement c3 gene expression characterization and innate immune response in Razor Clam sinonovacula constricta
Fish & Shellfish Immunology, 2016Co-Authors: Maoxiao Peng, Fei Wang, Zhiyi Chen, Jiale LiAbstract:Abstract Complement component 3 (C3) is central to the complement system, playing an important role in immune defense, immune regulation and immune pathology. Several C3 genes have been characterized in invertebrates but very few in shellfish. The C3 gene was identified from the Razor Clam Sinonovacula constricta , referred to here as Sc-C3 . It was found to be highly homologous with the C3 gene of Ruditapes decussatus . All eight model motifs of the C3 gene were found to be included in the thiolester bond and the C345C region. Sc-C3 was widely expressed in all healthy tissues with expression being highest in hemolymph. A significant difference in expression was revealed at the umbo larvae development stage. The expression of Sc-C3 was highly regulated in the hemolymph and liver, with a distinct response pattern being noted after a challenge with Micrococcus lysodeikticus and Vibrio parahemolyticus . It is therefore suggested that a complicated and unique response pathway may be present in S. constricta . Further, serum of S. constricta containing Sc-C3 was extracted. This was activated by LPS or bacterium for verification for function. The more obvious immune function of Sc-C3 was described as an effective membrane rupture in hemocyte cells of rabbit, V. parahemolyticus and Vibrio anguillarum. Thus, Sc-C3 plays an essential role in the immune defense of S. constricta .
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identification expression and innate immune responses of two insulin like peptide genes in the Razor Clam sinonovacula constricta
Fish & Shellfish Immunology, 2016Co-Authors: Fei Wang, Ze Wang, Honggang Zhao, Jiale LiAbstract:Insulin-like peptide (ILP) has emerged as a cell regulatory factor with multiple functions in vertebrates and invertebrates. In the present study, we identified and characterized two ILP genes, ILP1 and ILP2, in the Razor Clam Sinonovacula constricta. Both ILPs have a signal peptide and a mature domain consisting of six strictly conserved cysteines. The tertiary structure is divided into three main α-helices with a C-domain loop that separates helix 1 from helix 2. Both of ILPs were found to be regulated according to tissue type and developmental stage. After challenge with Vibrio anguillarum, Vibrio parahaemolyticus and Micrococcus lysodeikticus, the expression of two ILP genes was significantly up-regulated in the liver, hemocytes and mantle tissues, suggesting that the ILPs may play roles in the innate immunity in the Razor Clam Sinonovacula constricta.
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developmental transcriptome analysis and identification of genes involved in larval metamorphosis of the Razor Clam sinonovacula constricta
Marine Biotechnology, 2016Co-Authors: Fei Wang, Ze Wang, Maoxiao Peng, Jiale LiAbstract:The Razor Clam Sinonovacula constricta is an important commercial species. The deficiency of developmental transcriptomic data is becoming the bottleneck of further researches on the mechanisms underlying settlement and metamorphosis in early development. In this study, de novo transcriptome sequencing was performed for S. constricta at different early developmental stages by using Illumina HiSeq 2000 paired-end (PE) sequencing technology. A total of 112,209,077 PE clean reads were generated. De novo assembly generated 249,795 contigs with an average length of 585 bp. Gene annotation resulted in the identification of 22,870 unigene hits against the NCBI database. Eight unique sequences related to metamorphosis were identified and analyzed using real-time PCR. The Razor Clam reference transcriptome would provide useful information on early developmental and metamorphosis mechanisms and could be used in the genetic breeding of shellfish.
Dorotea Martinezpatino - One of the best experts on this subject based on the ideXlab platform.
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effects of stocking density on intermediate culture of the Razor Clam ensis arcuatus pharidae bivalvia
Aquaculture Research, 2015Co-Authors: Fiz Da Costa, Susana Nóvoa, Justa Ojea, Berta Barreiro, Dorotea MartinezpatinoAbstract:Commercial production of most bivalve species involves a phase of intermediate cultivation during which juveniles are grown under protected conditions until they can be transferred to the final grow-out location. Consequently, the aim of this study was investigating the effect of density on growth and survival in the intermediate culture of the Razor Clam Ensis arcuatus in raft. Two series of experiments were performed, using in the first experiment two holding systems: 5-L plastic bottles and PVC cylinders, both perforated, covered with a 1 mm mesh net to prevent Razor Clam escape and a 10-cm layer of coarse grained sand (300–1200 μm grain diameter). In this trial, two stocking densities were tested: 0.15 and 0.30 kg m −2 . In the second one-two densities were essayed (0.62 and 1.24 kg m −2 ) in the PCV cylinders. In the first experiment after 27 of trial higher growth in cylinders at low density was observed. At the end of this trial all juveniles died in the 5-L plastic bottles and higher growth and survival were recorded in the cylinders at low density. In the second experiment, significant differences in growth and survival were found on day 70, with the best results at low density. Five-L plastic bottles must be rejected as holding system for the intermediate culture of E. arcuatus and the PVC cylinders at low densities could be a good alternative. At the end of the experiment Razor Clams reached the adequate size for their transfer into the grow-out system.
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vibrios in hatchery cultures of the Razor Clam solen marginatus pulteney
Journal of Fish Diseases, 2014Co-Authors: Susana Prado, Dorotea Martinezpatino, Javier Dubert, F Da Costa, J L BarjaAbstract:Hatchery culture of the Razor Clam, Solen marginatus (Pulteney), has recently been developed in Galicia (NW Spain). However, recurrent episodes of mortalities of larval and post-larval cultures have been recorded during the course of various studies. The disease signs were similar to those described for other bivalve species in outbreaks caused by bacteria of the genus Vibrio. In this article, we present the results of microbiological monitoring of two batches of Razor Clams with different survival rates. All fermentative isolates were identified as members of the Splendidus clade within the genus Vibrio. Some of these isolates, identified as Vibrio splendidus-like, were clearly associated with the batch suffering mortalities, indicating their possible role as pathogens. Similar strains were found in the broodstock, suggesting vertical transmission of these bacteria. This is the first study of the microbiota associated with hatchery culture of S. marginatus, and the results will provide useful information for the optimization of a protocol for hatchery culture of this bivalve species.
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culture possibilities of the Razor Clam ensis arcuatus pharidae bivalvia
Aquaculture Research, 2011Co-Authors: Fiz Da Costa, Susana Darriba, Dorotea Martinezpatino, Alejandro GuerraAbstract:This study investigated Razor Clam Ensis arcuatus culture from larval rearing to commercial size to assess it's aquaculture potential. Broodstock was spawned several times in hatchery facilities to demonstrate that larval availability is not a constraint for hatchery production. Larval culture lasted 20 days, showing an average survival of 14.35%. The Razor Clam seed reached a size of 28.5 mm at 4 months. Seed culture is feasible; however, it is constrained by the fact that Razor Clams need to be buried. Higher survival was observed when culturing Razor Clam seed with a substrate (82–83%), irrespective of the substrate grain size, while containers held without a substrate showed a significantly lower survival (56.5%). We showed that it is possible to rear E. arcuatus juveniles in bottles, with survival as high as 94–95% being achieved. The length increase of the hatchery-produced E. arcuatus over 600 days was described by the equation Ln L=4.5+(−141.17/t), where L is length in mm and t is time in days. On-growing showed adequate survival rates and it took 2–3 years to reach commercial size.
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culture potential of the Razor Clam solen marginatus pennant 1777
Aquaculture, 2009Co-Authors: Fiz Da Costa, Dorotea MartinezpatinoAbstract:Abstract The objective of this study was to determine whether Solen marginatus could be cultured to commercial size. Fertilized eggs measured 156.2 µm in diameter and they were surrounded by a 30-µm-thick chorionic envelope. Settlement occurred on day 9 when a length of 302.6 µm was reached. The percentage of settlement varied between 28.2 and 80.9%. Growth of post-set Razor Clam spats was described by the equation L = 0.006 x 1.644 , where L = length in mm and x is the number of days of culture. The Razor Clam seed reached a length of 19.1 mm at 4 months. One-year-old juveniles measured 38.5 mm and commercial size was reached with three-year-old individuals (80.1 mm). Survival in the ongrowing experiment ranged between 50 and 83%. The life cycle of this species was closed, obtaining larvae from the individuals reared in the ongrowing experiment.
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genetic variation of the Razor Clam ensis siliqua jeffreys 1875 along the european coast based on random amplified polymorphic dna markers
Aquaculture Research, 2007Co-Authors: Juan Fernandeztajes, Dorotea Martinezpatino, Ana M Gonzaleztizon, Andres Martinezlage, Miguel B Gaspar, Niall Mcdonough, Dai Roberts, Josefina MendezAbstract:Ensis siliqua is regarded as an increasingly valuable fishery resource with potential for commercial aquaculture in many European countries. The genetic variation of this Razor Clam was analysed by randomly amplified polymorphic DNA (RAPD) in six populations from Spain, Portugal and Ireland. Out of the 40 primers tested, five were chosen to assess genetic variation. A total of 61 RAPD loci were developed ranging in size from 400 to 2000 bp. The percentages of polymorphic loci, the allele effective number and the genetic diversity were comparable among populations, and demonstrated a high level of genetic variability. The values of Nei's genetic distance were small among the Spanish and Portuguese populations (0.051–0.065), and high between these and the Irish populations. Cluster and principal coordinate analyses supported these findings. A mantel test performed between geographic and genetic distance matrices showed a significant correlation (r=0.84, P<0.05), suggesting an isolation by distance process.
Patricia Mirella Da Silva - One of the best experts on this subject based on the ideXlab platform.
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presence and histopathological effects of the parvatrema sp digenea gymnophallidae in the stout Razor Clam tagelus plebeius bivalvia psammobiidae
Journal of Invertebrate Pathology, 2009Co-Authors: Patricia Mirella Da Silva, Florencia Cremonte, Rachel Costa Sabry, Rafael Diego Rosa, Liege Cantelli, M A BarraccoAbstract:The stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae) has a wide geographic distribution range, including the Brazilian coasts from the northeast (Alagoas) to the south (Santa Catarina). In March 2008, an episode of mass T. plebeius mortality (70%) occurred in an intertidal bed at The Pontal da Daniela, State of Santa Catarina, Brazil. We report here high prevalences (to 100%) of the trematode parasite Parvatrema sp. Cable, 1953 (Digenea, Gymnophallidae) infecting T. plebeius at high intensities. We describe the gymnophalid, echinostomatid and unidentified metacercariae parasites infecting the Clam and the host reactions elicited by them. The use of special diagnostic techniques such as Ray’s fluid thioglycollate medium (RFTM) and PCR assays to detect Perkinsus sp. pathogens, hemolymph cytology, and histopathological examinations did not show Perkinsus sp. infections, microcell infections, or neoplastic conditions. However, neither infections or pathology caused by trematode parasites; nor any other pathological condition could be uniquely correlated with the mortality event. A coincident flash flood might have contributed to cause the mortality episode. This is the first report of the Parvatrema sp. metacercariae larvae infecting the stout Razor Clam T. plebeius from Brazil.
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Presence and histopathological effects of the Parvatrema sp. (Digenea, Gymnophallidae) in the stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae)
Journal of Invertebrate Pathology, 2009Co-Authors: Patricia Mirella Da Silva, Florencia Cremonte, Rachel Costa Sabry, Rafael Diego Rosa, Liege Cantelli, M A BarraccoAbstract:The stout Razor Clam Tagelus plebeius (Bivalvia, Psammobiidae) has a wide geographic distribution range, including the Brazilian coasts from the northeast (Alagoas) to the south (Santa Catarina). In March 2008, an episode of mass T. plebeius mortality (70%) occurred in an intertidal bed at The Pontal da Daniela, State of Santa Catarina, Brazil. We report here high prevalences (to 100%) of the trematode parasite Parvatrema sp. Cable, 1953 (Digenea, Gymnophallidae) infecting T. plebeius at high intensities. We describe the gymnophalid, echinostomatid and unidentified metacercariae parasites infecting the Clam and the host reactions elicited by them. The use of special diagnostic techniques such as Ray's fluid thioglycollate medium (RFTM) and PCR assays to detect Perkinsus sp. pathogens, hemolymph cytology, and histopathological examinations did not show Perkinsus sp. infections, microcell infections, or neoplastic conditions. However, neither infections or pathology caused by trematode parasites; nor any other pathological condition could be uniquely correlated with the mortality event. A coincident flash flood might have contributed to cause the mortality episode. This is the first report of the Parvatrema sp. metacercariae larvae infecting the stout Razor Clam T. plebeius from Brazil. © 2009 Elsevier Inc. All rights reserved.
