The Iguaçu River basin is a tributary to the upper Paraná River in southern Brazil, and is considered an important aquatic ecoregion that, although having few species of fish, 51-71% of these are apparently endemic. Ancistrus abilhoai is one of three recently described species for this basin and is currently considered endemic to the basin.
Hylidae is one of the most species-rich families of anurans, and 40% of representatives in this group occur in Brazil. In spite of such remarkable diversity, little is known about this family and its taxonomical and systematic features. Most hylids have 2n = 24, even though most of the cytogenetic data are mainly obtained based on the conventional chromosomal staining and are available for only 16% of Hypsiboas species, a genus accounting for about 10% of the hylid diversity.
In the present study, the karyotype and chromosomal characteristics of 9 species of the Bagridae fish family were investigated using conventional Giemsa staining as well as dual-color fluorescence in situ hybridization to detect the 18S and 5S rDNA sites. In addition to describing the karyotype of several Bagridae catfishes, we established molecular cytogenetic techniques to study this group.
In Carangidae, Caranx is taxonomically controversial because of slight morphological differences among species, as well as because of its relationship with the genus Carangoides. Cytogenetic data has contributed to taxonomic and phylogenetic classification for some groups of fish.
Hypochaeris is an excellent system for studying different modes of chromosome evolution in plants. We carried out a cytogenetic analysis on populations of 2 Hypochaeris species, comprising 10 populations of H. catharinensis and 5 of H. lutea, to assess possible changes on chromosome organization in this interesting genus.