Uncommon and classed as vulnerable at Cape Jervis, this eucalypt rarely tops a couple of metres in height here, though it will grow to about 10 m on Kangaroo Island. At Cape Jervis, they are stunted, multi-stemmed, sprawling mallee trees while on KI they can be more upright with a single stem. ‘rugosa’ is derived from the Latin ‘rugosos’ for ‘wrinkled’, so think of rough … but for the fruits and buds, not the bark! The bark is smooth and creamy-pink. White flowers appear in clusters from spring to autumn but these are not particularly showy. The buds are interesting though, as are the fruits. The buds form a group on a flattened stem, each bud on a small stalk or no stalk at all. Their caps have ridges on them, giving the roughness. These caps are also slightly flattened, and shorter than the base. The fruit are also slightly ribbed.