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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?

Reference:

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

Sometimes we get so used to seeing ants visiting extrafloral nectaries, it seems unexpected to see them visiting regular floral nectaries.

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Take this shrubby dogwood flower (probably gray dogwood, Cornus racemosa). The nectaries are the creamy yellow bands at the base of the female part of the flower (the pistil or carpel) in the center.

 

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Formica workers seemed to be visiting the plants most frequently, although other ants were in the area.

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Ants weren't the only insects attracted to the nectaries of the dogwood flowers.

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Along with the usual wasps, flies and bees, there were also more unusual true bugs and beetles.

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A number of the smaller butterflies stopped by, including hairstreaks and blues.

It turns out azure butterflies in particular are attracted to these types of dogwoods and lay their eggs on them. What happens next? Of course, the ants tend the azure caterpillars! Nature Posts blog has an incredible series of photographs and videos of ants tending azure butterfly caterpillars.

Interested in planting a garden for ants or butterflies? You might want to consider planting some of the dogwoods (Cornus sp.)

Have you ever seen azure caterpillars on dogwoods? I am definitely going to be looking from now on.

 

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Have you discovered David Louis Quinn's Pogolumina website yet? If you are interested in ants, Pogonomyrmex and/or photography, it is a must see.

David's new video Domain of the Thatching Ant, Part I is mesmerizing.  Take a look:

You know where I'll be spending all my free time for the next few week, looking through all the pages. He's already answered some questions I had about Pogonomyrmex workers harvesting plants around their mounds.

Thanks, David!

I'd love to hear your comments.