Dataset for: Rio de Janeiro and other paleodrainages evidenced by the genetic structure of an Atlantic Forest catfish

Aim: The disjunct distributions of freshwater organisms along coastal drainages are usually explained by paleodrainages formed during sea-level retreats that connected currently isolated basins, or by river capture from tectonic adjustments between adjoining watersheds. We evaluate the relative importance of these events on the genetic variation of freshwater fishes inhabiting the Serra do Mar in eastern Brazil, a region with steep mountains and pronounced bays.
Location: Coastal river drainages in southeastern Brazil.

Taxon: Catfishes of the Trichomycterus alternatus group.

Methods: We tested the effects of paleolandscape connections (GIS-reconstructed paleodrainages and putative river captures) on the genetic structure (mitochondrial and nuclear markers) of T. alternatus from 15 drainages using phylogenetic reconstructions, lineage delimitation methods and analyses of molecular variance.
Results: Trichomycterus alternatus is monophyletic and comprised of three main lineage...