This is Paropsisterna lineata, a mostly black and highly nitid (glossy) beetle with a few consistent yellow lines along the striae. This is a nocturnal species and found in the daytime hiding in the gaps in stringy-bark bark. I have not found it on other species of eucalyptus. I have not found it except under bark. Also seen in Croydon, Ferntree Gully, the Basin and Tasmania.
This beetle is Paropsis erudita. It is a highly nitid (glossy) species found under bark of smooth barked eucalyptus spp. such as manna gum. This is the more scarce of the nocturnal leaf beetles in my experience and found only twice. Also seen at Wonga Park (Mt Lofty) and Healesville. It lacks striae grooves and puncturation is very fine. There are two very smart looking red diagonal lines on the combined elytra in the form of a chevron.