Dimitri Ramos Alves

Community ecology of the metazoan parasites of pink cusk-eel, Genypterus brasiliensis (Osteichthyes: Ophidiidae), from the coastal zone of the State of Rio de Janeiro, Brazil

Fifty-five specimens of pink cusk-eel, Genypterus brasiliensis Regan, 1903 (Osteichthyes: Ophidiidae) collected from the coastal zone of the State of Rio de Janeiro, Brazil (approx. 21-23 degrees S, 41-45 degrees W), from September 2000 to January 2001, were necropsied to study their parasites. All fish were parasitized by one or more metazoan. Fourteen species of parasites were collected. G. brasiliensis is a new host record for nine parasite species. The larval stages of cestodes and the nematodes were the majority of the parasite specimens collected, with 38.4% and 36.5%, respectively. Cucullanus genypteri was the dominant species with highest prevalence and/or abundance. The parasites of G. brasiliensis showed the typical overdispersed pattern of distribution. Six parasite species showed correlation between the hosts total body length and prevalence and abundance. Host sex did not influence prevalence and parasite abundance of any parasite species. The mean diversity in the infracommunities of G. brasiliensis was H= 0.364 +/- 0.103, with correlation with the hosts total length and without differences in relation to sex of the host. One pair of adult endoparasites (C. genypteri and A. brasiliensis) showed positive covariations between their abundances. Negative association or covariation was not found. Differences between the qualitative and quantitative aspects of the parasite community of G. brasiliensis from Rio de Janeiro and Argentina suggest the existence of two population stocks of pink cusk-eel in the South America Atlantic Ocean.

Ecologia das comunidades de metazoários parasitos, do xaréu, Caranx hippos (Linnaeus) e do xerelete, Caranx latus Agassiz (Osteichthyes, Carangidae) do litoral do estado do Rio de Janeiro, Brasil

Sixty specimens of Caranx hippos (Linnaeus, 1766) and fifty-five specimens of Caranx latus Agassiz, 1831 collected from the coastal zone of the State of Rio de Janeiro (21-23oS, 41-45oW), Brazil, from October 1998 to October 1999, were necropsied to study their metazoan parasites. All specimens of C. hippos were parasitized, and the majority of specimens of C latus (96.4%) were parasitized by one or more metazoan species. Nineteen species of parasites were collected in C. hippos: 5 digeneans, 5 monogeneans, 2 cestodes, 5 nematodes, and 2 copepods. Seventeen species of parasites were collected in C. latus: 6 digeneans, 2 monogeneans, 3 cestodes, 4 nematodes, and 2 copepods. The endoparasites (digeneans, cestodes, and nematodes) were the majoriry, 76.4% and 63.3%, of the total number of parasite specimens collected in C. hippos and C. latus, respectively. The monogeneans Allopyragraphorus hippos (Hargis, 1956) and Cemocotyle carangis (MacCallum, 1913) were the most dominant species with the highest parasitic prevalence in the parasite community of C. hippos and C. latus, respectively. The metazoan parasites of the two host species showed the typical overdispersed pattern of distribution. Bucephalus varicus Manter, 1940. A. hippos, Protomicrocotyle mirabilis (MacCallum, 1918), Cucullanus pulcherrimus Barreto, 1918, and Lemanthropus giganteus KrΦyer, 1863 had a positive correlation only between the hosts total length and abundance andlor prevalence in C. hippos. Bucephalus varicus, Tergestia pectinata (Linton, 1905), C. carangis, and Pseudoterranovo sp. had a positive correlation between the hosts total length and abundance and/or prevalence in C. latus. In C. hippos, the copepod Caligus robustus Bassett-Smith, 1898 had the highest values of prevalence and abundance in the female hosts. No parasite species showed influence of the hosts sex on their prevalence and abundance in C. latus. The mean diversity and the parasite species richness of the parasite infracommunities of C. hippos and C. latus were not significantly different. Only the parasite species diversity of C. hippos was correlated with the hosts total length; in both host species the parasite diversity did not showed differences in relation to the sex of the host. Only one pair of ectoparasite species, A. hippos - P. mirabilis, showed significant positive co-occurrence and covariation in the parasite infracommunities of C. hippos. Two endoparasite species, B. varicus - Parahemiurus merus (Linton, 1910), showed negative co-occurrence and positive covariation; and the pair B. varicus - Pseudoterranova sp. had positive co-occurrence and covariation in the infracommunities of C. latus. The values of qualitative and quantitative simila rity coefficients between the parasite communities of C. hippos and C. latus were 55.5 and 30.4, respectively. The parasite communities of C. hippos and C. latus were defined as closest to isolationist type because there are few evidences of interspecific associations or covariations. Additional parasitological studies on other species of carangid fishes from the South American Atlantic Ocean are needed to evaluate the structure of carangid parasite communities in the Neotropical region.

Aspectos quantitativos das infrapopulações de metazoários parasitos de Micropogonias furnieri (Osteichthyes: Sciaenidae) do litoral do estado do Rio de Janeiro, Brasil

Between September of 1997 and August of 1998, 40 specimens of Micropogonias furnieri were captured of the coastal zone of the State of Rio de Janeiro, Brazil (aprox. 21-23° S, 41-45° W), and examined to study quantitative aspects of their infrapopulations of metazoan parasites. All fishes were parasitized with at least one species of metazoan. A total of 760 parasites were collected, with average of 19/fish. Seventeen species of metazoan parasites were found. The nematode Dichelyne elongatus was the most prevalent and abundant parasite of M. furnieri. All parasite species of M. furnieri showed a typical pattern of distribution. Clavellotis dilatata had a positive correlation between the total length and parasite prevalence, and Pachycreadium gastrocotylum showed negative correlation. Pterinotrema-toides mexicanum, Macrovalvitrema sinaloense, Dichelyne elongatus and C. dilatata showed positive correlation between the total length and the parasite abundance while P. gastrocotylum showed negative correlation. The sex of the host not influenced the prevalence and abundance of the metazoan parasites

Metazoarios parásitos de micropogonias furnieri, osteichthyes sciaenidae, do litoral do Estado do Rio de Janeiro Brasil

Between September of 1997 and August of 1998, 40 specimens of Micropogonias furnieri were captured of the coastal of the State of Rio de Janeiro, Brazil (aprox. 21-23° S, 41-45° W), and necropsied to study of their metazoan parasites. Seventeen species of metazoan parasites were identified, 1 aspidobothrid, 3 digeneans, 3 monogeneans, 1 cestode, 2 acantocephalans, 2 nematodes, 1 hirudinean, 3 copepods and 1 isopod. Micropogonias furnieri is a new host record for Brachadena pyriformis Linton, 1910; Caligus haemulonis Kroyer, 1863; and Clavellotis dilatata (Kroyer, 1863). Neobrachiella chevreuxii (van Beneden, 1891) and Dichelyne elongatus (Tornquist, 1931) were recorded by the first time from Brazil.

Metazoários parasitos do peixe espada, Trichiurus lepturus (Osteichthyes: Trichiuridae) do litoral do estado do Rio de Janeiro, Brasil

Between January and November of 1999, 55 specimens of Atlantic cutlassfish, Trichiurus lepturus Linnaeus, 1758 were captured of the coastal of the State of Rio de Janeiro, Brazil (21-23° S, 41-45° W), and necropsied to study of their metazoan parasites. Eleven species of metazoan parasites were collected in T. lepturus: 1 digenean, 1 monogenean, 2 cestodes, 1 acantocephalan, 5 nematodes, and 1 copepod. Trichiurus lepturus is a new host record for Callitetrarhynchus gracilis, Hysterothylacium sp., and Raphidascaris sp., Octoplectanocotyla trichiuri and Polymorphus sp. were recorded for the first time in Brazil.

Pseudolernentoma brasiliensis n. g., n. sp. (Copepoda: Poecilostomatoida: Chondracanthidae) parasitic on Genypterus brasiliensis (Osteichthyes: Ophidiidae) from off the State of Rio de Janeiro, Brazil

Pseudolernentoma, a new chondracanthid genus was proposed to accommodate Pseudolernentoma brasiliensis n. g., n. sp., parasitic on the pink cusk-eel Genypterus brasiliensis Regan, from off the coast of Rio de Janeiro, Brazil. The new genus can be differentiated from the other genera of the Chondracanthidae by the presence of an inflated head with lateral expansions and anteroventral bifurcate processes on the trunk.

A new species of Anoplodiscus (Monogenea: Anoplodiscidae) parasitic on Pagrus pagrus (Osteichthyes: Sparidae) from the coastal zone of the State of Rio de Janeiro, Brazil

A new species of Anoplodiscus (Monogenea, Anoplodiscidae), parasitic on gills of the red porgy, Pagrus pagrus, from the coastal zone of the State of Rio de Janeiro, Brazil, is described and illustrated. The new species can be differentiated from the other species of this genus by the shape of the accessory piece of the copulatory complex, and the length of the vagina. This is the first record of a species of Anoplodiscus in the Neotropical region.

Metazoan parasites of Mandi-amarelo Pimelodus maculatus and of Jundiá Rhamdia quelen (Osteichthyes: Siluriformes) of Paraíba do Sul River, Volta Redonda, Rio de Janeiro

Forty-one specimens of mandi-amarelo Pimelodus maculatus Lacépède, 1803 (Siluriformes: Pimelodidae) and 54 specimens of jundiá Rhamdia quelen (Quoy & Gaimard, 1824) (Siluriformes: Heptapteridae) were collected from the Paraíba do Sul River, Volta Redonda, State of Rio de Janeiro, Brazil between November 2007 and October 2008. These fish underwent necropsy so their infracommunities of metazoan parasites could be studied. The same three species of parasites were collected in the two fish species studied. These were one monogenean, one nematode, and one hirudinean. Cucullanus pinnai (Travassos, Artiga, and Pereira, 1928) (Nematoda: Cucullanidae) and Aphanoblastella sp. (Monogenea: Dactylogyridae) were the dominant species with the highest prevalence in P. maculatus and R. quelen. The parasite species of P. maculatus and R. quelen showed an atypical over-dispersed pattern of distribution. No parasite species showed significant correlation between the body total length of the siluriform hosts and their prevalence and abundance. The parasite species richness showed a mean value of 0.87 ± 0.67 (0-2) and 0.57 ± 0.56 (0-2) in P. maculatus and R. quelen, respectively, and no correlation with the body total length.

Metacercárias de Clinostomum marginatum (Digenea: Clinostomidae) em acará-bandeira Pterophyllum scalare (Osteichthyes: Cichlidae) no estado do Rio de Janeiro, Brasil

The present study recorded by the first time metacercariae of the digenetic Clinostomum marginatum (Clinostomidae) infecting specimens of the ornamental fish Pterophyllum scalare, from the State of Rio de Janeiro, Brazil. Parasites were found encysted on the fins of the fish, forming small, white-yellowish, nodules

Aspectos ecológicos de las infrapoblaciones de Cucullanus genypteri (Nematoda: Cucullanidae) parásito del congrio rosado, Genypterus brasiliensis (Osteichthyes: Ophidiidae) del litoral del estado de Rio de Janeiro, Brasil

Entre septiembre de 2000 y enero de 2001 fueron necropsiados 55 especimenes de congrio rosado, G. brasiliensis procedentes de la costa del estado del Rio de Janeiro (21-23° S, 41-45° W), Brasil. Todos los congrios examinados estaban parasitados por C. genypteri, colectandose un total de 1.312 especimenes; con abundancia media de 23,8 ± 26,7. Cucullanus genypteri presento un tipico patron de distribucion sobredispersa o contagiosa. La abundancia de C. genypteri presento correlacion positiva con el tamano corporal del hospedador. El sexo de los peces no influencio en la abundancia del parasito.