Anisakid nematode larvae from Trichiurus lepturus off coast of Rio de Janeiro were studied using light, laser confocal and scanning electron microscopy, in addition to a molecular approach. Mitochondrial cytochrome c-oxidase subunit 2 (mtDNA cox-2), partial 28S (LSU) and internal transcribed spacers (ITS-1, 5.8S, ITS-2) of ribosomal DNA were amplified using the polymerase chain reaction and sequenced to evaluate the phylogenetic relationships between the nematode taxa. The morphological and genetic profiles confirmed that, of the 1,030 larvae collected from the 64 fish examined, 398 were analysed, of which 361 were Hysterothylacium sp. and 37 were Anisakis typica. Larvae of Hysterothylacium sp. were not identified to the species level due to the absence of similar sequences for adult parasites; however, the ITS sequence clustered in the phylogenetic tree with sequences of H. deardorffoverstreetorum, whereas an mtDNA cox-2 and LSU concatenated phylogenetic analysis demonstrated the presence of two clades, both of them under the same name as the larval H. deardorffoverstreetorum. Data on the occurrence of parasites during the winter and summer months were compared using the t-test. The greatest prevalence and intensity of infection were recorded for larval Hysterothylacium, with a prevalence of 51.56% and an intensity of up to 55 parasites per fish. The larval Anisakis exhibit a higher abundance and intensity of infection in the winter months, and those of Hysterothylacium during the summer. However, the t-test indicated no significant differences between the abundance and intensity of infection recorded during the months of collection for either of these larval nematodes. All sequences generated in this study were deposited in GenBank.

Viability of Cryptocotyle lingua metacercariae from Atlantic cod (Gadus morhua) after exposure to freezing and heating in the temperature range from -80 °C til 100 °C. Food Control, 50,[371][372][373][374][375][376][377] Viability of Cryptocotyle lingua metacercariae from Atlantic cod (Gadus morhua) after exposure to freezing and heating in the temperature range from À80 C to 100 C a b s t r a c tThe presence of parasites in fish products is a problem that concerns consumers and authorities due to the potential hazards it may cause. The majority of studies on the viability of parasites in marine fish products currently focus on nematodes of the family Anisakidae whereas only few are concerned with trematodes. In this study on the heterophyid trematode Cryptocotyle lingua (identified by morphometric and molecular techniques) we isolated metacercariae from Atlantic cod (Gadus morhua) and incubated the parasites in cod muscle tissue at different temperatures ranging from À80 C to 100 C and subsequently tested their viability. SEM images were made to assess the physical damage caused to parasites exposed to different temperatures. Temperatures between 50 C and 100 C and between À80 C and À20 C killed the metacercariae present in fish flesh in less than 2 h. Controls kept at 5 C survived for nine days. Extreme freezing temperatures caused minimal visual physical damage to cysts, but the tegument of metacercariae was severely affected at all temperatures when incubated for long periods.

Morphological and genetic data on the larvae of Anisakidae parasitizing the sandperches Pseudopercis numida and Pinguipes brasilianus were recorded from Cabo Frio, State of Rio de Janeiro, Brazil (23°S, 42°W). Twenty-five specimens of P. numida and 25 specimens of P. brasilianus were necropsied. The 352 larvae collected included 1 Anisakis sp., 344 Hysterothylacium sp., and 7 Raphidascaris sp. We present mtDNA sequence data for Anisakis sp. and Hysterothylacium sp., and we sequenced the ITS ribosomal DNA (rDNA) of Hysterothylacium sp. and Raphidascaris sp. The morphological and genetic profiles confirmed the identification of Anisakis typica (Diesing, 1860). Hysterothylacium sp. and Raphidascaris sp. were not identified to the species level due to the absence of similar sequences for adult parasites. The mtDNA sequence of Hysterothylacium sp. from P. numida showed a high similarity to the sequence of Hysterothylacium deardorffoverstreetorum. However, a phylogenetic analysis demonstrated the presence of different clades under the same name as the larval H. deardorffoverstreetorum. Pseudopercis numida is a new host record for A. typica.

Pygidiopsis macrostomum and Ascocotyle (Phagicola) pindoramensis (Digenea: Heterophyidae) parasitize guppies as intermediate hosts and, respectively, fish‐eating mammals or birds as definitive hosts. Heterophyids have zoonotic potential, and molecular studies associated with morphological and ecological aspects have helped to clarify their taxonomy and phylogeny. Poecilia vivipara naturally parasitized by metacercariae of both species (100% prevalence) exhibit no external signs of parasitism. In this work, four new sequences of P. macrostomum (18S rDNA, 28S rDNA and ITS2 rDNA) and one new sequence of A. (P.) pindoramensis (mtDNA cox‐1) are presented. Phylogeny reconstructions linked P. macrostomum to other heterophyids, but the separation of the Heterophyidae and Opisthorchiidae remains unclear. Additionally, we used indirect immunocytochemistry and the phalloidin‐fluorescence techniques allied with confocal laser scanning microscopy to describe muscular and neuronal structures of P. macrostomum. A complex arrangement of muscular fibres is associated with the tegument, suckers, gut and reproductive system. Radial fibres around the ventral sucker are thick, branched and extend to the body wall. High‐resolution confocal imaging revealed a typical digenean muscular arrangement and important heterophyid morphological traits. These data will support future control measures to reduce the parasitism in guppies reared in fish farming systems, especially for aquarium and experimental purposes.

An anisakid nematode larva found in cod sold in the state of Minas Gerais, Brazil was studied by light and scanning electron microscopy and by a molecular approach. Mitochondrial cytochrome c-oxidase subunit 2 (mtDNA cox-2), 28S rRNA and ITS1, 5.8S and ITS2 regions were amplified using the polymerase chain reaction and sequenced to evaluate the phylogenetic relationships of the larva. The genetic profile confirmed that this larva belongs to the species Pseudoterranova decipiens (sensu stricto). This is the first molecular and ultrastructural study of Pseudoterranova decipiens (sensu stricto) in imported cod sold in Brazil. The health implications of these findings are discussed.Keywords: Anisakiasis, codworm, food safety, public health. ResumoUma larva de Nematoda anisakídeo encontrada em bacalhau comercializado no Estado de Minas Gerais, Brasil foi estudada por microscopias de luz e eletrônica de varredura e por uma abordagem molecular. As regiões da subunidade 2 da citocromo c-oxidase mitocondrial (mtDNA cox-2), 28S rRNA e ITS1, 5.8S e ITS2 foram amplificadas usando a reação em cadeia da polimerase e sequenciadas para avaliar as relações filogenéticas da larva. O perfil genético confirmou que esta larva pertence à espécie Pseudoterranova decipiens (sensu stricto). Esse é o primeiro estudo molecular e ultraestrutural de Pseudoterranova decipiens (sensu stricto) de bacalhau importado vendido no Brasil. As implicações destes resultados para a saúde são discutidas.Palavras-chave: Anisakíase, bacalhau, segurança alimentar, saúde pública.

Three new sequences of Mitochondrial cytochrome c-oxidase subunit 2 (mtDNA cox-2) from C. pelagicum parasite of Spheniscus magellanicus, the Magelanicus penguin, were determined from Brazilian waters. The sequences presented 99 and 98% of similarity with C. pelagicum sequences from Argentina, deposited on GenBank for the same genetic region and with a strong statistical support inferred from the phylogenetic tree. The morphological and ultrastructural studies that were carried out confirmed the genetic analysis.Keywords: Anisakidae, penguin, Rio de Janeiro. ResumoForam determinadas três novas sequências da região do Citocromo c-oxidase da subunidade II do DNA mitocondrial (cox-2 mtDNA) de Contracaecum pelagicum, parasito de Spheniscus magellanicus, pinguim Magalhães, de águas brasileiras. As sequências apresentaram 99 e 98% de similaridade com sequências de C. pelagicum da Argentina depositadas no GenBank da mesma região genética com forte suporte estatístico inferido pela arvore filogenética. Estudos morfológicos e ultraestruturais realizados confirmaram a identidade genética.

Fish-borne heterophyid trematodes are known to have a zoonotic potential, since at least 30 species are able to infect humans worldwide, with a global infection of around 7 million people. In this paper, a ‘state-of-the-art’ review of the South American heterophyid species is provided, including classical and molecular taxonomy, parasite ecology, host-parasite interaction studies and a list of species and their hosts. There is still a lack of information on human infections in South America with undetected or unreported infections probably due to the information shortage and little attention by physicians to these small intestinal flukes. Molecular tools for specific diagnoses of South American heterophyid species are still to be defined. Additional new sequences of Pygidiopsis macrostomum, Ascocotyle pindoramensis and Ascocotyle longa from Brazil are also provided.

A redescription of the aspidogastrean trematode Lobatostoma kemostoma (MacCallum & MacCallum, 1913) is provided based on examination of type material, voucher specimens available at institutional collections and newly collected specimens from the type host, Trachinotus carolinus (Linnaeus, 1766), off the Angra dos Reis, Brazil. Partial sequence of its 28S rDNA is given. Lobatostoma kemostoma can be distinguished from the other eight species of the genus by: (1) the hindbody being longer than the ventral disc; and (2) the cephalic lobes having the same shape and size. Features observed for the first time include the number and detailed arrangement of alveoli on the ventral disc, the terminal genitalia and the ovarian complex. New illustrations and morphometric data are given. In the present survey the host specificity in the genus, the validity of some morphological features and the occurrence of an Indian species of Lobatostoma from off the Brazilian coast are discussed. A lectotype of L. kemostoma from the type series deposited at United States National Parasite Collection is also designated.