Phylogenetic relationships and historical biogeography of Oligosarcus (Teleostei: Characidae): Examining riverine landscape evolution in southeastern South America.

The pike-characin Oligosarcus is a group of Characidae composed of 22 species, which have mostly allopatric distributed species in southeastern South America and sympatric occurrence of few species. Oligosarcus shares a similar distribution pattern with other fish genera and therefore, can help us to understand biogeographic events that influenced freshwater fish distribution in the southeastern South America. Our paper presents the most extensive taxonomic coverage for molecular analysis of Oligosarcus and uses various methods to examine the evolutionary history of the genus.

Metazoan parasites of Geophagus brasiliensis (Perciformes: Cichlidae) in Patos Lagoon, extreme south of Brazil.

This study has evaluated the parasitic fauna of 79 pearl cichlids (Geophagus brasiliensis) from the estuary of Patos Lagoon (31° 57' S and 52° 06' W), Rio Grande do Sul, Brazil, during the months of May and June in 2011 and 2012. All the hosts analyzed were infected with at least one species of parasite. A total of eleven metazoa were identified in 459 specimens collected.

Presence of eggs of Toxocara spp. and hookworms in a student environment in Rio Grande do Sul, Brazil.

Environmental contamination by parasite forms was studied on a university campus in the municipality of Pelotas, Rio Grande do Sul. Soil samples were analyzed using the modified Caldwell & Caldwell technique to identify parasite forms. Nematode eggs were detected in 62% of the samples.