Marcelo Knoff

Genetic and morphological characterisation of a new species of the genus Hysterothylacium (Nematoda) from Paralichthys isosceles Jordan, 1890 (Pisces: Teleostei) of the Neotropical Region, state of Rio de Janeiro, Brazil

Taking into account the difficulties of taxonomic identification of larval anisakid nematodes based on morphological characters, genetic analyses were performed, together with those usually applied, in order to identify anisakid larvae found in the flounder Paralichthys isosceles from the littoral of the state of Rio de Janeiro, Brazil. The analysis of 1,820 larvae revealed a new species, similar to Hysterothylacium MD, Hysterothylacium 2, Hysterothylacium KB and Hysterothylacium sp regarding the absence of the larval tooth, an excretory pore situated below the nerve ring level, and slender lateral alae. Moreover, the new species differs from Hysterothylacium fortalezae and Hysterothylacium reliquens with regard to the number and size of spines present on the tail end and from Hysterothylacium patagonicus by the absence of interlabia. The maximum parsimony and neighbour joining tree topologies based on the 18S ribosomal DNA gene, complete internal transcribed spacer region and cytochrome oxidase 2 (COII) gene demonstrated that the Brazilian larvae belong to Raphidascarididae and represent a unique genetic entity, confirmed as a new Hysterothylacium species. Furthermore, the new species presents COII genetic signatures and shares polymorphisms with Raphidascarididae members. This is the first description of a new anisakid species from Brazil through the integration of morphological and molecular taxonomy data.

Anisakidae parasitos de congro-rosa, Genypterus brasiliensis Regan, 1903 comercializados no estado do Rio de Janeiro, Brasil de interesse na saúde pública

The aim of this study was to identify the species Anisakidae, of interest to public health, parasitizing the cusk-eel, Genypterus brasiliensis Regan, 1903 purchased in markets ofNiteroi and Rio de Janeiro counties, Brazil, emphasizing their parasite indexes, sites of infection and higienic-sanitary importance. Seventy-four specimens ofG brasiliensis were necropsiedfrom October 2002 to September 2003. Twenty fish specimens (27%>) were parasitized by live larvae of Anisakidae. The collected species were represented by Anisakis physeteris, Anisakis simplex, Anisakis sp., Pseudoterranova decipiens, Pseudoterranova sp., Hysterothylacium sp., Raphidascaris sp., Contracaecum sp. and Terranova sp. The species Anisakis sp. and A. simplex presented the higher prevalences, both with 13,5% whereas A. physeteris presented the lower prevalence 1,35%. The other species, Pseudoterranova sp., P. decipiens, Hysterothylacium sp., Raphidascaris sp., Contracaecum sp. and Terranova sp. presented prevalences of 10,8%, 5,4%, 2,7%, 4,1%, 1,4% and 1,4%, respectively. The sites of infection were, the mesentery, stomach and intestinal seroses, intestine, ovary and musculature.

Nematodes of elasmobranch fishes from the southern coast of Brazil

New records for nematode species recovered from elasmobranch fishes in Brazil are established and new systematical arrangements proposed. Parascarophis sphyrnae Campana-Rouget, 1955 from the spiral valve of Sphyrna zygaena is referred for the first time in South America as a new host record. Procamallanus (S.) pereirai Annereaux, 1946, from the spiral valve of Raja castelnaui is reported parasitizing an elasmobranch host. Nematode larvae of the genera Anisakis, Contracaecum, Pseudoterranova and Raphidascaris are listed from the stomach and spiral valves of several hosts. Anisakidae larvae previously referred in Brazil in the genus Phocanema should be reallocated in Pseudoterranova. Nematodes of the genera Anisakis, Contracaecum, Pseudoterranova and Raphidascaris are reported for the first time parasitizing elasmobranchs in Brazil.

Digenea and Acanthocephala of Elasmobranch Fishes from the Southern Coast of Brazil

New records for helminth species recovered from elasmobranch fishes in Brazil are established. Digenean and acanthocephalan parasites of elasmobranch fishes are reported from the southern coast of Brazil: Otodistomum veliporum (Creplin, 1837) Stafford, 1904 (Digenea: Azygiidae) in the stomach and spiral valve of Dipturus trachydermus and in the spiral valve of Squatina sp. Cystacanths and juveniles of the acanthocephalans Corynosoma australe Johnston, 1937 and Corynosoma sp., in the spiral valve of Squatina sp., Galeorhinus galeus and Hexanchus griseus and in the stomach of Squalus megalops; a juvenile of Gorgorhynchus sp., in the spiral valve of Sphyrna zygaena. Dipturus trachydermus and Squatina sp. are new host records for O. veliporum. Digeneans and acanthocephalans are reported for the first time parasitizing elasmobranch fishes in Brazil.

Anisakidae nematodes and Trypanorhyncha cestodes of hygienic importance infecting the king mackerel Scomberomorus cavalla (Osteichthyes: Scombridae) in Brazil.

From February to October 2007, thirty specimens of the king mackerel, Scomberomorus cavalla (Cuvier, 1829) were purchased from markets in the municipalities of Niterói and Rio de Janeiro. The fishes were measured, filleted and further had their organs investigated for helminths. Ten out of the thirty fish specimens were parasitized with anisakid nematodes represented by Anisakis sp. and Contracaecum sp. with prevalence of 1% and 16%, mean intensity of 2 and 3.31 and mean abundance of 0.02 and 0.53, respectively. The infection range with Contracaecum sp. was 1-9. The sites of infection were the stomach serosa and mesentery. Seventeen fish specimens (53%) out of the 30 investigated were parasitized with Trypanorhyncha metacestodes, identified as Callitetrarhynchus gracilis, Pterobothrium crassicole, Callitetrarhynchus speciosus and Tentacularia coryphaenae in the mesentery, with prevalence of 26, 20, 6, 3%, intensity and mean intensity of 3.25, 3.5, 1, 2 and mean abundance of 0.86, 0.7, 0.06 and 0.06, respectively. The infection range due to C. gracilis and P. crassicole were of 1-5 and 1-20, respectively. Anisakis sp., C. speciosus and P. crassicole are reported in S. cavalla for the first time. Considerations on the zoonotic potential of the parasites and their rules in sanitary inspection are presented.

Larvae of Hysterothylacium sp. (Nematoda: Anisakidae) in the sole fish Paralichthys isosceles Jordan, 1890 (Pisces: Teleostei) from the littoral of the state of Rio de Janeiro, Brazil.

Sixty specimens of Paralichthys isosceles captured in the southeastern Brazilian coast were investigated for helminths from October 2006 to March 2008. One thousand eight hundred and twenty larvae (third and fourth stages) of Hysterothylacium sp. were recovered from the abdominal cavity, free or inserted in the mesentery, intestine, stomach, stomach wall, liver, spleen, ovaries, and serosas of heart, kidneys, ovaries and abdominal musculature. Gross lesions appeared as nodules in the stomach mucosa and intestinal serosa. Histological examination of these nodules revealed sections of Hysterothylacium sp. larvae inserted in the abdominal musculature, in the submucosa, muscular and serosa layers of the stomach and intestine. Associated granulomas consisted of fibrous connective tissue, macrophages and lymphocytes that surrounded, besides the larvae, necrotic material and tunnels with acidophilic lining, sometimes devoid of inflammatory reaction. The pathological alterations as well as the occurrence of Hysterothylacium sp. are reported for the first time in this host. The parasitic indexes refer to a prevalence of 100%, mean intensity of 30.3, mean abundance of 32 and range of intensity variation from 1 to 596.

Nematoides anisaquídeos e cestoides Trypanorhyncha de importância em saúde pública em Aluterus monoceros (Linnaeus, 1758) no Estado do Rio de Janeiro, Brasil

One hundred specimens of unicorn leatherjacket, Aluterus monoceros purchased from markets of municipalities of Niteroi and Rio de Janeiro from May to August 2006. The fishes were measured, necropsied, fileted and analysed their organs. Sixteen fishes were parasitized by nematode Anisakidae: Anisakis spp. and Contracaecum sp. with respectively, 1 and 16% of prevalence, 2 and 3.31 of mean intensity, and 0.02 and 0.53 of mean abundance. Two larvae of Anisakis sp. were found in mesentery of one fish and Contracaecum sp. was found in liver and mesentery with 1 to 9 specimens of range of infection. Fifty-one fishes were parasitized on the liver and mesentery by metacestodes of Trypanorhyncha. The collected species were Floriceps saccatus and Callitetrarhynchus speciosus with respectively, 45 and 6% of prevalence, 3.17 and 2.83 of mean intensity, and 1.43 and 0.06 of mean abundance, the range of infection by F. saccatus was 1 to 20 and by C. speciosus was 1 to 5. Anisakis sp. and these two species of Trypanothyncha were reported in A. monoceros for the first time.

Total mercury in sharks along the southern Brazilian Coast

Pesquisou-se a concentracao de mercurio total na porcao muscular de 39 exemplares de tubaroes de tres diferentes especies Prionace glauca, Isurus oxyrhynchus, Sphyrna zygaena, capturados na costa sul do Brasil, Santa Catarina. O teor de mercurio foi determinado por espectrofotometria de absorcao atomica por vapor frio. Observou-se ampla variacao na concentracao de mercurio total com valor individual maximo excedendo o limite estabelecido pela legislacao brasileira, de 1.0µg.g-1 em um exemplar femea de P. glauca. Nessa especie, a concentracao de Hg-total aumentou proporcionalmente ao comprimento total (r=0,62; P<0,0001). Nao foi evidenciada diferenca estatisticamente significativa entre exemplares femeas e machos.

Taxonomic reports of Otobothrioidea (Eucestoda, Trypanorhyncha) from elasmobranch fishes of the southern coast off Brazil

Specimens of elasmobranch fishes, captured in the states of Paraná and Santa Catarina, of the southern coast off Brazil, represented by three families, four genera, and four species, were parasitized with otobothrioid trypanorhynch cestodes: Heptranchias perlo (Bonnaterre, 1788), Squalus sp. and Carcharhinus signatus (Poey, 1868) were parasitized with Progrillotia dollfusi Carvajal & Rego,1987; Prionace glauca (Linnaeus, 1758) with Molicola horridus (Goodsir, 1841) Dollfus, 1942. Details of internal morphology and/or scolex and/or proglottids surface ultrastructure, that expanded the description of M. horridus, through observations with lightfield, and/or scanning eletronic microscopy, are provided. The known geographical distribution for the species M. horridus is enlarged. P. dollfusi is reported for the first time in elasmobranchs.

Prevalência e intensidade de infecção de cestóides Trypanorhyncha de elasmobrânquios nos estados do Paraná e Santa Catarina, Brasil

Twenty-nine specimes (32.2%) of elasmobranch fishes, out of 90 captured in the south coast of Brazil in the States of Parana and Santa Catarina, represented by six families, seven genera and nine species, were parasitized with cestodes of the order Trypanorhyncha: Heptranchias perlo and Squalus sp. parasitized with Progrillotia dollfusi; Isurus oxyrinchus with Nybelinia lingualis and Gymnorhynchus isuri; Prionace glauca with Tentacularia coryphaenae, Hepatoxylon trichiuri, Molicola horridus, Floriceps saccatus and Callitetrarhynchus gracilis; Carcharhinus signatus with Heteronybelinia yamagutii, H. nipponica and P. dollfusi; C. longimanus and C. obscurus with T. coryphaenae; Sphyrna zygaena with Heteronybelinia rougetcampanae and Callitetrarhynchus speciosus; Dipturus trachydermus with Mixonybelinia beveridgei. Prevalences and intensities of infection are presented as well as the analysis of the hosts sex-related parasitism, in single or concomitant infections. Data are discussed and compared with previous available reports on these hosts, mainly those referring to the species I. oxyrinchus, P. glauca and C. longimanus