No roos but heaps of hoppers

It looks like a battle scene from Lord of the Rings, but what you are seeing is a very peaceful trophobiotic relationship (an association where food is provided) between adult Black Gumtree Hoppers (black wings with brown heads), their nymphs (black, red and yellow) and Sugar Ants (Camponotus consobrinus).

Eurymelessa moruyana?

Gumtree Hoppers (Eurymela spp.)  like cicadas are of the Order Hemiptera. This means they are characterised by having sucking mouthparts and feed by extracting the sap from young trees. The food trees are primarily eucalypts (in this case a Yellow Box, Eucalyptus melliodora) but also include acacias (wattles) and allocasuarinas (she-oaks).  They feed in large groups of adults and nymphs.

Treehoppers exude a sugar-rich liquid known as honeydew. This is what ants feed on. In

Ant tending treehopper

exchange for this nourishment the ants provide the gumtree hoppers with protection from other predators. In separate trees in the same stand of young Yellow Boxes, different species of treehoppers were tended by different species of ants (see photo right). A truly symbiotic relationship. Any excess honeydew remains on the eucalypt leaves and leads to the growth of sooty mould.

If the top photo was a battle scene, being Hemipterans the battle cry would be ‘Suck on this’.