Lecithochirium monticellii digenetic trematode parasites of Trichiurus lepturus (Actinopterygii) from the state of Rio de Janeiro, Brazil, with notes on its taxonomy.

Trichiurus lepturus (Actinopterygii, Perciformes) is a commercially and economically important fish. A total of 60 specimens of this cutlassfish were collected of the coast the municipalities of Niterói and Cabo Frio, state of Rio de Janeiro, Brazil. The fish were measured, necropsied, filleted and had their organs investigated for digenetic trematodes. Taxonomic identification was based on morphological and morphometric characters. The specimens of T. lepturus were parasitized with adult specimens of Lecithochirium monticellii. Parasite indices of prevalence, intensity, mean intensity, abundance, mean abundance, range of infection, and site of infection of parasitic species were evaluated. Notes on the taxonomy of the parasite were also included. This is the first report of L. monticellii parasitizing T. lepturus in Brazil.

Pterobothrium crassicolle parasitizing Paralichthys orbignyanus (Osteichthyes, Paralichthyidae) in Brazil.

From September 2014 to November 2015, 30 Paralichthys orbignyanus specimens were obtained from Sepetiba Bay in the municipality of Rio de Janeiro, State of Rio de Janeiro, Brazil. The fishes were necropsied and cestode larvae were recovered from the abdominal cavity, mesentery, and serosas of the stomach, intestine, spleen, liver, kidney and gonads. Nineteen fish were parasitized by a total of 90 trypanorhynch plerocerci. Based on morphological characters, these were identified as Pterobothrium crassicolle. The parasitism indices for P. crassicolle on P. orbignyanus, were 63.3% for prevalence, 4.7 for mean intensity, 3 for mean abundance and 1 to 18 for range of infection. These parasites were studied due to their importance during fish sanitary inspection, if one considers the harm that the repulsive aspect of infected fish may cause to consumers. This is the first record of P. crassicolle plerocerci parasitizing P. orbignyanus.

Nematode larvae infecting Priacanthus arenatus Cuvier, 1829 (Pisces: Teleostei) in Brazil.

From July to December, 2013, thirty Priacanthus arenatus specimens commercialized in the cities of Niterói and Rio de Janeiro, State of Rio de Janeiro, were acquired. The fish were necropsied and filleted to investigate the presence of nematode larvae. Twenty fish (66.7%) out of the total were parasitized by nematode larvae. A total of 2024 larvae were collected; among them, 30 third-instar larvae of Anisakis sp. showed prevalence (P) = 20%, mean abundance (MA) = 1, and the mean intensity (MI) = 5, and infection sites (IS) = caecum, stomach, liver, and mesentery; and 1,994 third-instar larvae (1,757 encysted and 237 free) of Hysterothylacium deardorffoverstreetorum with P = 66.7%, MA = 66.5, and MI = 99.7, and IS = spleen, caecum, stomach, liver, mesentery, and abdominal muscle. This is the first study to report H. deardorffoverstreetorum and Anisakis sp. larvae parasitizing P. arenatus.

A new species of Heterosentis Van Cleave, 1931 (Acanthocephala: Arhythmacanthidae) parasitic in Pseudopercis numida Miranda Ribeiro, 1903 (Perciformes: Pinguipedidae) from southeastern Brazilian coastal zone.

Heterosentis brasiliensis n. sp. (Acanthocephala, Arhythmacanthidae), parasitic in namorado sandperch Pseudopercis numida Miranda-Ribeiro, 1903 (Perciformes, Pinguipedidae) from the littoral of Cabo Frio, State of Rio de Janeiro, Brazil, is described and illustrated herein. Heterosentis brasiliensis n. sp. differs from all congeneric species by having 10 longitudinal rows of hooks in the proboscis, 6 or 7 hooks in each row, 3 or 4 small basal hooks in each row, and spines in the anterior ventral surface of the body. The similar species, Heterosentis heteracanthus (Linstow, 1896) and Heterosentis caballeroi Gupta & Fatma, 1983, also have 10 longitudinal rows of hooks, but H. heteracanthus differs from the new species by possessing trunk spines in the ventral and dorsal body surface. Heterosentis caballeroi differs from H. brasiliensis by the presence of 1 apical and 1 subapical hook in each longitudinal row; the largest apical, subapical, and basal hooks; lemnisci that are smaller than the proboscis receptacles; and a pre-equatorial male reproductive system. This is the first record of a Heterosentis species in a pinguipedid fish and from Brazilian coastal zone.

[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.