#1524 - Horn Lerps - Creiis sp.
The eucalypts out at the Dryandra Woodlands were absolutely INFESTED with Jumping Plant Lice, and most of them were in the genus Creiis as far as I can tell. Of all the insects I was collecting over the weekend, Psyllids outnumbered anything else about 100-to-1.
Psyllids nymphs build shelters from excreted sugar, called Lerps, and the shape of the lerp is specific to genus. The horn-shaped ones here are among the least elaborate, but are large for a psyllid.
The plague of lerps isn’t a new thing - I’ve found reports of other population explosions at Foxes Lair and other parts of Western Australia, and it’s most likely related to the stress the trees are under. Combined with drought, a psyllid infestation can be enough to kill a tree.
One species of Psyllid, Diaphorina citri, is a serious threat to citrus crops outside Asia, because it is a vector of Citrus Greening Disease.