Cotana castaneorufa is a moth in the Eupterotidae family. It was described by Rothschild in 1913. It is found in New Guinea. The wingspan is about 49 mm. The forewings are chocolate liver-brown with a tiny white dot at the base, an antemedian buff stigma followed by a buff transverse band which is distinct and broad at the costal half, growing narrower and indistinct on the inner half. There is a more or less indistinct postdiscal transverse greyish-olive outwardly curved chain of half moons. The hindwings are orange, the outer two-thirds almost completely suffused with liver-brown. There is a brown transverse line in the basal one-third and an orange one somewhat sinuate in the outer one-third.