Determining Management Units in Southeastern Brazil: The Case of Astyanax bimaculatus (Linnaeus, 1758) (Teleostei: Ostariophysi: Characidae)

Abstract

Characterization, management and protection of biodiversity are the most prominent challenges in conservation biology. Analyses on molecular similarity (Random Amplified Polymorphic DNA-Polymerase Chain Reaction, RAPD-PCR) and morphologic patterns (morphometric and meristic characters) were performed to evaluate the existence of population structuring in the Doce river basin, in a widespread small-sized characin, Astyanax bimaculatus. Three hundred (300) individuals were collected from six locations isolated by waterfalls or dams, in the Doce river basin, Minas Gerais State, Brazil. Genetic differentiation among tributaries was significant (p<0.00001) and accounted for 21% of total variance (p<0.00001). Only the Grande waterfall of the Casca river was an effective factor for differentiation of populations (p<0.00001), and meristic characters were also consistent with molecular data. We concluded that genetic and morphologic variation of this species was not necessarily associated with waterfalls and that molecular and meristic data are effective predictors of population divergence in this basin. The consequences of these findings for the protection and management of aquatic biodiversity were discussed.

Cytogenetic and comparative morphology of two allopatric populations of Astyanax altiparanae Garutti & Britski, 2000 (Teleostei: Characidae) from upper rio Paraná basin

“…Based on the present report, we present another hypothesis; the occurrence of different stocks of A. altiparanae along the rio Iguaçu basin could be a consequence of the formation history of this basin, its ancient lakes and connections with adjacent basins such as the upper Tibagi, Ribeira de Iguape and Paraná rivers. This hypothesis seems to be in agreement with the data found by Paiva et al (2006) for Astyanax bimaculatus from the rio Doce basin. In this case, genetic and morphological variations do not reflect exclusively events of allopatric speciation but indicate divergence at the population level.…”

Cytogenetic and morphological diversity in populations of Astyanax fasciatus (Teleostei, Characidae) from Brazilian northeastern river basins

“…Similarly, RAPD-PCR, meristic, and morphometric analyses in five samples of Astyanax aff. bimaculatus separated by waterfalls and dams along Doce River basin have shown a concordance between molecular and morphological data (Paiva et al, 2006). Microsatellite, allozymes, mtDNA, and morphometric studies in sympatric populations of the catfish Clarias gariepinus and C. anguillaris have all confirmed the presence of distinct species (Agnèse et al, 1997).…”

Características de carcaça de galinha naturalizada Peloco comparada a linhagens de frango caipira

“…Quanto maior o valor da variação explicada pelo primeiro componente principal, maior é a eficiência desta análise (Paiva et al, 2006;Silva et al, 2009 (1) Médias seguidas de letras iguais, maiúsculas nas colunas e minúsculas nas linhas, não diferem entre si, pelo teste Tukey, a 5% de probabilidade. *Significativo a 5% de probabilidade, pelo teste F. ns Não significativo.…”