Two new species of Acanthobothrium Blanchard, 1848 (Cestoda: Onchoproteocephalidea) from rajiform batoids off Argentina.

Two new species of Acanthobothrium Blanchard, 1848 were collected from rajiform batoids along the coast of Argentina. They are Acanthobothrium carolinae sp. n. from Bathyraja magellanica (Philippi) and Acanthobothrium domingae sp. n. from Dipturus brevicaudatus (Marini). Both belong to category 1 and 2 because their total length is lower than 15 mm, they have fewer than 50 proglottids, fewer than 80 testes and a symmetric or asymmetric ovary. Acanthobothrium carolinae sp. n. differs from all congeners by the following combination of features: proglottid apolysis, hook morphology, microthrix pattern on the cephalic peduncle and distribution of the vitelline follicles. Acanthobothrium domingae sp. n. is unique in the combination of proglottid apolysis, total length, number of proglottids, hook and septal morphology, microthrix pattern on the cephalic peduncle, number and distribution of testes, cirrus sac length, distribution of the vitelline follicles and genital pore position. The discovery of these species increases the number of species of Acanthobothrium parasitising rajiform batoids off Argentina from one to three. All three species have a unique pattern of distribution of the gladiate spinitriches along the length of the cephalic peduncle, i.e., gladiate spinitriches being interrupted in a medial line both dorsally and ventrally.

Four New Species of Paraorygmatobothrium (Eucestoda: Phyllobothriidea) From Sharks of the Gulf of Mexico and the Atlantic Ocean, with Comments on Their Host Specificity.

Four new species of Paraorygmatobothrium are described from carcharhinid shark species from the Gulf of Mexico and the U.S. coast of the northwestern Atlantic Ocean. Paraorygmatobothrium bullardi n. sp. is described from Carcharhinus brevipinna as its type host, and from Carcharhinus acronotus and Carcharhinus limbatus. Paraorygmatobothrium campbelli n. sp. is described from Rhizoprionodon terraenovae. Paraorygmatobothrium deburonae n. sp. is described from Carcharhinus isodon as its type host, as well as from C. brevipinna, C. limbatus, and R. terraenovae. Paraorygmatobothrium mattisi n. sp. is described from R. terraenovae as its type host, and from C. brevipinna and C. limbatus. These 4 species differ from other species of Paraorygmatobothrium and from each other in bothridial microthrix shape, and in various combinations of features such as the total length of the worm, apical sucker size, bothridial musculature, proglottid number, testes number, and genital pore position. Difficulty in differentiating these 4 species from one another, and from other species of Paraorygmatobothrium, points to limitations in the use of morphology alone to recognize species diversity in this genus. A phylogenetic analysis of Paraorygmatobothrium and related genera, based on partial (D1-D3) 28S rDNA sequence data, confirms that the genus is not monophyletic. Genetic distances of COI revealed that sequence divergence between species of Paraorygmatobothrium is generally at least an order of magnitude larger than COI divergence within a species. Patterns of host use for 3 of the new species are consistent with previous findings that point to a lack of host specificity in Paraorygmatobothrium.

Krill Nyctiphanes simplex gonad affection associated with acute-intensity phyllobothriid plerocercoid infection.

This is the first acute-intensity record of helminths parasitizing the subtropical krill Nyctiphanes simplex Hansen, 1911. We briefly describe the pathology of infection of Phyllobothriidae gen. sp. plerocercoids parasitizing N. simplex in the Gulf of California. Infection occurred with a very low prevalence (P = 0.06%, n = 1563 specimens), although acute-intensity exceeded several hundred plerocercoids crowding the hemocoel in one female host. Nyctiphanes simplex showed inflammatory response of hemocyte-based infiltration, nodule formation, and presumptive melanization. Remarkably, cestodes invade and supplant the gonad, causing atretic oocytes and severe tissue destruction in the gonad likely leading to castration and cell death in connective tissue of the infected organs suggesting that acute-intensity infection exceeds the krill's reaction capacity. Thus, Phyllobothriidae gen. sp. negatively affects the host by depleting its fitness, leading to total castration to prevent/block host reproduction.

Callitetrarhynchus gracilis (Rudolphi, 1819) Pintner, 1931 (Cestoda: Trypanorhyncha) parasitizing the musculature of Sardinella brasiliensis (Steindachner, 1879) (Actinopterygii) off the coast of the state of Rio de Janeiro, Brazil.

Cestodes of the order Trypanorhyncha can frequently be found infecting the muscles of several marine fish species, and lead to a repugnant aspect of the fish and rejection by consumers. The Brazilian sardinella, Sardinella brasiliensis, occurs from the Gulf of Mexico and the Caribbean to northern Uruguay. In southeastern Brazil, fishing for the species is very intensive since it generates significant revenue as one of the most commonly consumed fish and an important element of the canned fish industry. The aims of the present study were to identify and report the occurrence of tiny cestodes (3 mm-6.6 mm) in the musculature of Brazilian sardinella that were purchased in the São Pedro fish market in the municipality of Niterói, state of Rio de Janeiro, Brazil. From October 2013 to November 2016, 75 specimens of S. brasiliensis were investigated. The trypanorhynch cestodes encountered were identified as plerocerci of Callitetrarhynchus gracilis using morphological, morphometric and molecular data. Parasitic indices were calculated, and the cestodes infection of the musculature of Brazilian sardinella had the following values: prevalence, 40%; mean intensity, 3.47; mean abundance, 1.39; and range of infection, 1-18, specimens. The presence of this trypanorhynch cestode in the musculature of Brazilian sardinella is an important indicator of fish hygiene.

Analysis of classical neurotransmitter markers in tapeworms: Evidence for extensive loss of neurotransmitter pathways.

Parasitic flatworms have complex neuromuscular systems that serve important functions in their life cycles. However, our understanding of neurotransmission in parasitic flatworms is limited. Pioneering studies have suggested the presence of several classical neurotransmitter systems, but their molecular components have not been characterized in most cases. Because these components are conserved in bilaterian animals, we searched the genomes of parasitic flatworms for orthologs of genes required for neurotransmitter synthesis, vesicular transport, reuptake, and reception. Our results indicate that tapeworms have lost the genes that are specifically required in other animals for synaptic signaling using the classical neurotransmitters dopamine, tyramine, octopamine, histamine and gamma-aminobutyric acid (GABA). These results imply that these signaling pathways are either absent in these parasites, or that they require completely different molecular components in comparison with other animals. The orthologs of genes related to histaminergic and GABA signaling are also missing in trematodes (although Schistosoma-specific histaminergic receptors have been previously described). In contrast, conserved genes required for glutamatergic, serotonergic and cholinergic signaling could be found in all analyzed flatworms. We analyzed the expression of selected markers of each pathway in the tapeworm Hymenolepis microstoma by whole-mount in situ hybridization. Each marker was specifically expressed in the nervous system, although with different patterns. In addition, we analyzed the expression of proprotein convertase 2 as a marker of peptidergic cells. This gene showed the widest expression in the nervous system, but was also expressed in other tissues, suggesting additional roles of peptidergic signaling in tapeworm development and reproduction.

Octopus maya parasites off the Yucatán Peninsula, Mexico. I. Faunal assemblages.

The red octopus Octopus maya Voss et Solís-Ramírez, 1966 is an endemic species found exclusively off the coast of the Yucatán Peninsula, Mexico; its fishery is one of the most important along the Atlantic coast of Mexico and the Caribbean Sea. To date, the parasite fauna of Octopus spp. in southern Mexico remains unknown. In this study, we present the parasite fauna of O. maya from 8 localities along the Yucatán Peninsula. From August 2009 to June 2010, a total of 1202 specimens of O. maya were caught by artisanal fisheries and examined. Twenty parasite taxa were recorded from all octopus examined: 7 cestodes, 8 digeneans, 3 nematodes, 1 copepod and 1 coccidian. All taxa are new records for this host species, and the sampled locations represent new records of the geographic distribution of these parasite taxa. The gills and the intestine were the micro-habitats in which the highest number of taxa were found. More than half of the parasites (13 taxa) that we found infected O. maya via its feeding habits, although a high number of taxa (n = 9) colonized via active transmission. Cestoda and Digenea were the taxonomic groups with the highest number of taxa. Prochristianella sp. showed the highest prevalence and mean abundance values in the localities where it was present. This work represents the first study on the parasite fauna of any cephalopod species in Mexico.

Octopus maya parasites off the Yucatán Peninsula, Mexico. II. Salivary gland damage by cestodes.

The red octopus Octopus maya Voss et Solís-Ramírez, 1966 is an endemic species and one of the most important fishery resources of the Yucatán Peninsula, Mexico. Due to its economic importance and the fact that in recent years interest in farming this species has increased, several initiatives have been implemented to study its biology and requirements for cultivation. Parasites represent an important component of the biology of the red octopus, as they can have an impact on both wild and cultivated populations. A total of 44 O. maya specimens were sampled from the fishing ports of Ría Lagartos and Dzilam de Bravo, Yucatán; specimens were measured and subsequently subjected to histological analysis of the buccal masses where cestode larvae (Prochristianella sp.) were found in the anterior salivary glands. Results of a chi-squared test showed that specimen size class and infestation levels (parasite abundance) were significantly correlated, with parasite damage levels more pronounced in larger animals. The damage caused to the anterior salivary glands by this parasite could have serious implications for feeding and reproductive success of O. maya.

Unique pharmacological properties of serotoninergic G-protein coupled receptors from cestodes.

BACKGROUND: Cestodes are a diverse group of parasites, some of them being agents of neglected diseases. In cestodes, little is known about the functional properties of G protein coupled receptors (GPCRs) which have proved to be highly druggable targets in other organisms. Notably, serotoninergic G-protein coupled receptors (5-HT GPCRs) play major roles in key functions like movement, development and reproduction in parasites. METHODOLOGY/PRINCIPAL FINDINGS: Three 5-HT GPCRs from Echinococcus granulosus and Mesocestoides corti were cloned, sequenced, bioinformatically analyzed and functionally characterized. Multiple sequence alignment with other GPCRs showed the presence of seven transmembrane segments and conserved motifs but interesting differences were also observed. Phylogenetic analysis grouped these new sequences within the 5-HT7 clade of GPCRs. Molecular modeling showed a striking resemblance in the spatial localization of key residues with their mammalian counterparts. Expression analysis using available RNAseq data showed that both E. granulosus sequences are expressed in larval and adult stages. Localization studies performed in E. granulosus larvae with a fluorescent probe produced a punctiform pattern concentrated in suckers. E. granulosus and M. corti larvae showed an increase in motility in response to serotonin. Heterologous expression revealed elevated levels of cAMP production in response to 5-HT and two of the GPCRs showed extremely high sensitivity to 5-HT (picomolar range). While each of these GPCRs was activated by 5-HT, they exhibit distinct pharmacological properties (5-HT sensitivity, differential responsiveness to ligands). CONCLUSIONS/SIGNIFICANCE: These data provide the first functional report of GPCRs in parasitic cestodes. The serotoninergic GPCRs characterized here may represent novel druggable targets for antiparasitic intervention.

Cestode parasites release extracellular vesicles with microRNAs and immunodiagnostic protein cargo.

Intercellular communication is crucial in multiple aspects of cell biology. This interaction can be mediated by several mechanisms including extracellular vesicle (EV) transfer. EV secretion by parasites has been reported in protozoans, trematodes and nematodes. Here we report that this mechanism is present in three different species of cestodes, Taenia crassiceps, Mesocestoides corti and Echinococcus multilocularis. To confirm this we determined, in vitro, the presence of EVs in culture supernatants by transmission electron microscopy. Interestingly, while T. crassiceps and M. corti metacestodes secrete membranous structures into the culture media, similar vesicles were observed in the interface of the germinal and laminated layers of E. multilocularis metacestodes and were hardly detected in culture supernatants. We then determined the protein cargo in the EV-enriched secreted fractions of T. crassiceps and M. corti conditioned media by LC-MS/MS. Among the identified proteins, eukaryotic vesicle-enriched proteins were identified as expected, but also proteins used for cestode disease diagnosis, proteins related to neurotransmission, lipid binding proteins as well as host immunoglobulins and complement factors. Finally, we confirmed by capillary electrophoresis the presence of intravesicular RNA for both parasites and detected microRNAs by reverse transcription-PCR. This is the first report of EV secretion in cestode parasites and of an RNA secretion mechanism. These findings will provide valuable data not only for basic cestode biology but also for the rational search for new diagnostic targets.

Cestodes of the blue shark, Prionace glauca (Linnaeus 1758), (Carcharhiniformes: Carcharhinidae), off the west coast of Baja California Sur, Mexico.

The cestode species recovered from the spiral intestines of 27 blue sharks (Prionace glauca) (Linnaeus, 1758) are reported from the western coast of Baja California Sur (BCS). The sampling was undertaken on a monthly basis from January 2003 to January 2004. The helminthological examination indicated the presence of four species of cestodes: Platybothrium auriculatum Yamaguti, 1952; Prosobothrium japonicum Yamaguti, 1934; Anthobothrium caseyi (Yamaguti, 1934) Ruhnke & Caira, 2009; and Paraorygmatobothrium prionacis (Yamaguti, 1934) Ruhnke, 1994. Of all the 27 sharks examined, 88.8% were infected with at least one cestode species. The most frequent species was P. auriculatum infecting 85% of the spiral intestines examined. In contrast the species with the highest mean intensity was P. prionacis (80.4 200). The species richness of cestodes in P. glauca is very similar in other regions of the world despite its wide distribution; however, this richness is low compared with other species of sharks within the same family. The feeding and host-specific are important factors that influence the parameters of infection of cestodes in this shark. On the west coast of BCS, Prionace glauca feeds mainly on red crab Pleuroncodes planipes Stimpson, 1860; squids Gonatus californiensis Young, 1972, Ancistrocheirus lesueurii (D'Orbigny, 1842), Haliphron atlanticus Steenstrup, 1861, and low proportion of fish teleosts as Merluccius productus (Ayres, 1855), Sardinops sp. Hubbs, 1929 and Scomber japonicus Houttuyn, 1872. We speculate that these prey could be involved as the second intermediate hosts of these cestodes, as in other members of these genera, although the life cycles of none are known.

Metazoan parasites of Brama australis from southern Chile: a tool for stock discrimination?

The metazoan parasites of 403 specimens of the southern ray's bream Brama australis from three localities in southern Chile (Lebu 36° 70' S; 73° 40' W, Calbuco 41° 50' S; 73° 08' W and Punta Arenas 53° 10' S; 70° 50' W) were recorded. More than 23 400 parasite specimens belonging to 12 taxa were registered. Metazoan parasites were dominated by the copepod Hatschekia conifera, constituting 97% of the total number of parasites; the larval cestode Hepatoxylon trichiuri was the second most important parasite (2·1% of the total number of parasites). The remaining 10 species constituted <1% of the metazoan parasites. Parasitological evidence, based on univariate and multivariate analysis, does not support the existence of discrete stocks in the studied zone.

A new species of Heteronybelinia (Cestoda: Trypanorhyncha) from Sympterygia bonapartii (Rajidae), Nemadactylus bergi (Cheilodactylidae) and Raneya brasiliensis (Ophidiidae) in the south-western Atlantic, with comments on host specificity of the genus.

Adults and plerocercoids of a new species of Heteronybelinia (Trypanorhyncha, Tentaculariidae) were recovered from the skate Sympterygia bonapartii (Rajiformes: Rajidae) and two species of teleosts, Raneya brasiliensis (Ophidiiformes: Ophidiidae) and Nemadactylus bergi (Perciformes: Cheilodactylidae), respectively. Heteronybelinia mattisi n. sp. differs from its congeners in its possession of a tentacular armature consisting of hooks with slight differences in size and shape on opposite surfaces of the tentacle (uncinate with rounded bases on the bothrial surface and uncinate with elongate bases on the antibothrial surface), without a characteristic basal armature, hooks increasing in size toward the tip of the tentacles, and pars bothrialis slightly overlapping with bulbs. The description of Heteronybelinia is emended regarding the distribution of testes to include species without postovarian testes (H. palliata and H. mattisi), and without testes anterior to cirrus sac on the poral side (H. robusta and H. mattisi). Host data are summarized for all 15 valid species of Heteronybelinia. Host specificity of adults and plerocercoids of Heteronybelinia is variable among species, the adults being more host specific than the plerocercoids. With the exception of H. mattisi, the definitive hosts of all species of Heteronybelinia for which adults are known include carcharhiniform sharks. Heteronybelinia mattisi seems to have oioxenous specificity for its definitive batoid host, S. bonapartii, and to be more specific for the intermediate hosts than most of its congeners.

Identification of parasites in Puffinus puffinus (Birds, Procellariiformes) from Northeastern Brazil.

Studies on the parasitic fauna of migratory sea birds of the Puffinus genus are scarce. Therefore, the aim of this study was to identify parasites of 16 specimens of Puffinus puffinus (Procellariiformes, Procellariidae) that died during the period of June 2011 to December 2011 at the Wildlife Screening Center (CETAS) of the Brazilian Institute of Environment and Natural Resources (IBAMA) in Cabedelo, Paraíba. During necropsy, biting lice and/or gastrointestinal helminths were collected in seven (43.7 %) birds. Lice were collected in five (31.2 %) birds, and the species identified were Halipeurus diversus, Trabeculus aviator, Austromenopon paululum), Saemundssonia sp. and Naubates sp. The prevalence of helminths was also 31.2 %. The nematodes species were Seuratia shipleyi and Contracaecum sp., and cestodes were Tetrabothrius sp. This is the first record in Brazil of Naubates sp., Seuratia shipleyi, Contracaecum sp., and Tetrabothrius sp. in Puffinus puffinus.

Metacestodes of Glossocercus auritus (Cyclophyllidea, Gryporhynchidae) in Poecilia reticulata (Pisces, Poeciliidae) from Brazil.

Studies on fish parasites in Pampulha dam, Belo Horizonte, Minas Gerais, Brazil, found specimens of Poecilia reticulata Peters, 1859 harboring natural infection by larval stages of tapeworms. A total of 250 specimens of P. reticulata were collected and analyzed between February and August 2010, of which 23 were found infected (prevalence 9.2%) with one metacestode each (mean intensity 1, mean abundance 0.09). The analyses of the parasites, particularly the morphology of rostellar hooks, made it possible to identify Glossocercus auritus (Rudolphi, 1818). This is the first report of G. auritus metacestode in South America and P. reticulata is a newly known host for this parasite.

Metacestodes of Glossocercus auritus (Cyclophyllidea, Gryporhynchidae) in Poecilia reticulata (Pisces, Poeciliidae) from Brazil / Metacestoides de Glossocercus auritus (Cyclophyllidea, Gryporhynchidae) em Poecilia reticulata (Pisces, Poeciliidae) no Brasil

Studies on fish parasites in Pampulha dam, Belo Horizonte, Minas Gerais, Brazil, found specimens of Poecilia reticulata Peters, 1859 harboring natural infection by larval stages of tapeworms. A total of 250 specimens of P. reticulata were collected and analyzed between February and August 2010, of which 23 were found infected (prevalence 9.2 percent) with one metacestode each (mean intensity 1, mean abundance 0.09). The analyses of the parasites, particularly the morphology of rostellar hooks, made it possible to identify Glossocercus auritus (Rudolphi, 1818). This is the first report of G. auritus metacestode in South America and P. reticulata is a newly known host for this parasite.

Em estudo da helmintofauna de peixes oriundos da represa da Pampulha, Belo Horizonte, Minas Gerais, Brasil, exemplares de Poecilia reticulata Peters, 1859 foram encontrados naturalmente infectados por larvas de cestóides. De 250 espécimes de P. reticulata coletados e analisados entre fevereiro e agosto de 2010, 23 (prevalência de infecção 9,2 por cento) apresentavam-se infectados por um metacestóides cada (intensidade média 1, abundância média 0,09). A análise dos parasitos, em especial a morfologia dos acúleos rostelares, permitiram a identificação de Glossocercus auritus (Rudolphi, 1818). Este é o primeiro registro de metacestóide de G. auritus para a América do Sul, sendo P. reticulata um novo hospedeiro conhecido para o parasito.

Monticellia santafesina n. sp. (Cestoda: Proteocephalidea), a parasite of Megalonema platanum (Günther) (Siluriformes: Pimelodidae) in the Paraná River basin, Argentina.

The proteocephalidean tapeworm Monticellia santafesina n. sp. is described from the siluriform catfish Megalonema platanum (Günther) (Siluriformes: Pimelodidae) in the Paraná River basin, Argentina. The new species is allocated to Monticellia La Rue, 1911 (Proteocephalidae: Monticelliinae) because of the cortical position of the testes, ovary, vitelline follicles and uterus, a globular scolex without a metascolex and uniloculate suckers. The new species differs from all other species of Monticellia (except for M. lenha Woodland, 1933) in possessing a vaginal canal opening anterior or posterior to the cirrus-sac. M. santafesina can be distinguished from M. lenha by the following characteristics: a larger body size; a weakly developed internal longitudinal musculature arranged in 15-35 slim bundles of muscle fibres; vitelline follicles not interrupted at the level of the cirrus-sac and vaginal canal, and with a few paramuscular and/or medullary follicles; the absence of large spinitriches on the anterior margin of the suckers; and the utilisation of Megalonema platanum (in the Paraná River basin) as its host, rather than Sorubimichthys planiceps (Spix & Agassiz) (in the River Amazon). Monticellia santafesina exhibits low values of prevalence (9%) and intensity of infection (1). Megalonema platanum was parasitised by two proteocephalidean cestodes, Rudolphiella cf. lobosa (Riggenbach, 1895) and the new species described in this paper.

Characterization of a diversity of tetraphyllidean and rhinebothriidean cestode larval types, with comments on host associations and life-cycles.

Life-cycles of marine tapeworms of the orders Tetraphyllidea and Rhinebothriidea are poorly known primarily because their larvae typically lack species level, taxonomically distinguishing adult characteristics and using morphology they can be identified to genus, family or order only. This large-scale study conducted in the northern Gulf of Mexico includes adult cestodes (25 species) collected from sharks and rays (Elasmobranchii, eight species) and larval cestodes (27 species) collected from teleosts (Neopterygii, 46 species), bivalves and gastropods (Mollusca, 24 species), and shrimps (Crustacea, five species), comprising a phylogenetically (75 species in three phyla, 14 orders and 46 families) and ecologically (e.g., benthic, epibenthic, pelagic, euryhaline, stenohaline) diverse array of hosts of larval cestode. Molecular biology and morphology informed larval identification and facilitated the circumscription of suites of morphological features representing distinct larval types (i.e., collective groups). A total of 198 specimens comprising adult and larval tetraphyllideans and rhinebothriideans assigned to 12 genera were characterized for the partial (D1-D3) lsrDNA gene and analyzed separately and in combination with data derived from species belonging to an additional 21 genera available from GenBank. Eight larval types were identified and matched to one or several genera of Tetraphyllidea or Rhinebothriidea; morphological variation within these larval types was also documented. In combination with published reports of unique larval morphologies, 15 larval types were established and a key to their larvae presented. Overall, teleosts figured prominently in the life-cycles of tetraphyllideans and rhinebothriideans. Intermediate host specificity at the level of cestode genus was euryxenous, but limited host records suggest that host specificity at the level of cestode species may be more strict. To our knowledge, this is the first published study that approaches the elucidation of marine tapeworm life-cycles by incorporating morphological, molecular biological and phylogenetic methods using specimens collected on a regional scale and from wild-caught hosts from four metazoan phyla.

[Poecilancistrium caryophyllum (Diesing, 1850) (Cestoda, Trypanorhyncha), parasite of Macrodon ancylodon (Bloch & Schneider, 1801) from the Northern littoral of Brazil]. / Poecilancistrium caryophyllum (Diesing, 1850) (Cestoda, Trypanorhyncha), parasito de Macrodon ancylodon (Bloch & Schneider, 1801) do litoral Norte do Brasil.

The aim of this research was to report the presence of Trypanorhyncha cestodes, their prevalence and mean intensity in the muscles musculature and abdominal serose in commercial fish processed in Belém, Pará State. Fifty specimens of M. ancylodon were captured in the North Coast of Brazil. The musculature and adjacent abdominal serose of fish were analized in a "candling table" after filleted. Eight specimens were parasitized by plerocercoids of Poecilancistrium caryophyllum, with a prevalence of 16% and mean intensity of infection of one plerocercus per fish, varying from the unique site of infection was the musculature. The species P. caryophyllum is reported by the first time on M. ancylodon.The aim of this research was to report the presence of Trypanorhyncha cestodes, their prevalence and mean intensity in the muscles musculature and abdominal serose in commercial fish processed in Belém, Pará State. Fifty specimens of M. ancylodon were captured in the North Coast of Brazil. The musculature and adjacent abdominal serose of fish were analized in a "candling table" after filleted. Eight specimens were parasitized by plerocercoids of Poecilancistrium caryophyllum, with a prevalence of 16% and mean intensity of infection of one plerocercus per fish, varying from the unique site of infection was the musculature. The species P. caryophyllum is reported by the first time on M. ancylodon.

Poecilancistrium caryophyllum (Diesing, 1850) (Cestoda, Trypanorhyncha), parasito de Macrodon ancylodon (Bloch & Schneider, 1801) do litoral Norte do Brasil / Poecilancistrium caryophyllum (Diesing, 1850) (Cestoda, Trypanorhyncha), parasite of Macrodon ancylodon (Bloch & Schneider, 1801) from the Northern littoral of Brazil

O objetivo desta pesquisa foi registrar a presença de cestoides Trypanorhyncha, suas prevalências e intensidades de infecção, na musculatura e serosa abdominal parietal de 50 exemplares de Macrodon ancylodon, capturados no litoral Norte do Brasil e beneficiados em Belém, Estado do Pará, durante o período de junho de 2004 a janeiro de 2005. A musculatura e serosa abdominal dos peixes foram examinadas em mesa de inspeção candling table após o filetamento das amostras. Oito peixes encontravam-se parasitados por plerocercoides da espécie Poecilancistrium caryophyllum, com prevalência de 16 por cento e intensidade média de infecção de um plerocerco por peixe, tendo como único sítio de infecção a musculatura. A espécie Poecilancistrium caryophyllum é, pela primeira vez, registrada para M. ancylodon.

The aim of this research was to report the presence of Trypanorhyncha cestodes, their prevalence and mean intensity in the muscles musculature and abdominal serose in commercial fish processed in Belém, Pará State. Fifty specimens of M. ancylodon were captured in the North Coast of Brazil. The musculature and adjacent abdominal serose of fish were analized in a "candling table" after filleted. Eight specimens were parasitized by plerocercoids of Poecilancistrium caryophyllum, with a prevalence of 16 percent and mean intensity of infection of one plerocercus per fish, varying from the unique site of infection was the musculature. The species P. caryophyllum is reported by the first time on M. ancylodon.

[Trypanorhyncha cestodes parasitic in blackfin goosefish, Lophius gastrophysus Miranda-Ribeiro, 1915 purchased in the State of Rio de Janeiro, Brazil]. / Cestóides Trypanorhyncha parasitos de peixe sapo-pescador, Lophius grastrophysus Miranda-Ribeiro, 1915 comercializados no estado do Rio de Janeiro, Brasil.

The aim of this study was to determine the cestodes species of the order Trypanorhyncha that parasite the blackfin goosefish, Lophius gastrophysus Miranda-Ribeiro, 1915 purchased from fishermen, markets and exportation fish industries from municipalities of Cabo Frio, Niterói, Duque de Caxias and Rio de Janeiro, emphasizing their parasite indexes, sites of infection and higienic-sanitary importance. Eighty seven specimens of L. gastrophysus were necropsied from March 2000 to December 2005. Forty one fish (47%) were parasitized by metacestodes of Trypanorhyncha. The collected species were Tentacularia coryphaenae, Nybelinia sp., Mixonybelinia sp. and Progrillotia dollfusi. Most of the parasitized fish (92.7%), presented metacestodes of Trypanorhyncha, in the abdominal muscles and in muscles of commercial importance (lateral back-dorsum), belonging to the species T. coryphaenae, Nybelinia sp., Mixonybelinia sp. Only three (7.3%) fish specimens did not present trypanorhynch metacestodes in the muscles, two of them were parasitized by Nybelinia sp. on the mesentery and the celomatic cavity and the other by P. dollfusi on the celomatic cavity. On some individuals, Mixonybelinia sp. caused equimotic hemorragic lesions on the fascia of the abdominal muscles. The presence of Trypanorhyncha metacestodes in the muscles does not represent a risk of infection for humans, but they have a negative effect on fish aesthetics because of the repugnant aspect, causing consumer rejection and the prohibition for commercial purpose by sanitary inspectors. Parasites of the order Trypanorhyncha are recorded in L. gastrophysus for the first time.