Cycloramphus duseni is a species of frog in the family Cycloramphidae. It is endemic to southern Brazil and only known from its type series collected in 1911 from near Casa Ypiranga (or Ipiranga) along the Curitiba–Paranaguá railway, in the Serra do Mar, Paraná state. Prior to naming of Cycloramphus izecksohni in 1983, it was confused with this species. The specific name duseni honors Per Dusén, Swedish naturalist who collected the type series. Common name Ypiranga button frog has been coined for this species.

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