Time to knock the cobwebs off this blog with some new posts. Let’s start by taking a look at ants tending the aster hopper, Publilia concava.
This species of treehopper is relatively easy to find because the nymphs feed in aggregations on the underside of goldenrod leaves (Solidago altissima).
The relationship between ants and aster hoppers is a mutualism. The ants guard the treehoppers and drive away predators. In this case the ants were Formica sp.
In return, the nymphs supply food for the ants in the form of liquid honeydew. In the center of the photograph the nymph has curled its tubular abdomen to present food to the ant.
The adult female treehoppers lay their eggs in clusters and guard them until they hatch. Then the worker ants take over. In a recent study, Morales and Zink found adult female treehoppers with ants tending them were more likely to lay eggs than untended ones. At one site the researchers discovered egg laying per treehopper actually increases with the number of worker ants nearby.
If you’ve never watched ants tending aster hoppers, here’s a short video. (Unfortunately, the lighting conditions weren’t ideal and there was a breeze.).
You might think that the treehopper nymphs, as phloem feeders, would be rather sessile, but the nymphs move around more than you might expect. Morales and Zink suggest that treehoppers may respond to density of conspecifics as well as ants.
In any case, the relationship between aster hoppers and ants is an interesting one.
Have you ever seen aster hoppers tended by ants?
Morales MA, Zink AG (2017) Mechanisms of aggregation in an ant-tended treehopper: Attraction to mutualists is balanced by conspecific competition
PLOS ONE 12(7): e0181429. https://doi.org/10.1371/journal.pone.0181429
Morales, 2002. Ant-dependent oviposition in the membracid Publilia concava. Ecological Entomology. 27: 247-250. (download .pdf)
Previous post about the treehopper on thistle, Entylia carinata