The yellow-crowned brush-tailed rat, Isothrix bistriata, is a South American brush-tailed rat species from the family Echimyidae. It is found in Bolivia, Brazil, Colombia, Ecuador, Peru, and Venezuela.
They are nocturnal and arboreal animals found in lowland evergreen rainforest, probably restricted to igapó and várzea habitats. Sometimes they can be seen at the entrances of their dens, which are often in tree holes (especially hollow palms) on the borders of rivers.
