Myrtartona mariannae is a species of moth in the Zygaenidae family. It is only known from Milmerran in south-eastern Queensland. The length of the forewings is 8.5 millimetres (0.33 in) for males. The wings are elongate. The forewing is slender and somewhat triangular, while the hindwing is almost rectangular but roundedApically. The forewing upperside and underside are greyish brown. The hindwing is dark grey with a brownish tinge, but slightly paler medially.