Abandoned Hornet Nest over the Chattahoochee River in Fall

October 14th, 2012 - 10:04 PM | Filed under Featured Photos | No comments

October 13, 2012 | Roswell, GA, USA

In Fall, bald-faced hornets enter the autumn of their lives. Surviving adults, no longer responsible for providing masticated prey for the colony’s growing young, enter into a retirement of sorts. They abandon their nest and spend their last days, up until the first frost, feeding on nectar. Only mated queens survive to found new colonies the following year.

 

 

Yellow/Black Treehoppers with Ants

July 14th, 2012 - 9:06 PM | Filed under Featured Photos | No comments

~5mm | January 7, 2012 | Tupaciguara, Minas Gerais, Brazil

Here’s yet a different species of colorful treehopper. These too were found in association with ants.

A busy photo, but packed with natural history.

Ants Tending Treehoppers, Poorly Perhaps

July 9th, 2012 - 11:36 PM | Filed under Featured Photos | No comments

~3mm | January 7, 2012 | Tupaciguara, Minas Gerais, Brazil

I had planned to post just a single photo of this scene with ants tending treehoppers. Here we see at least two different colorful treehopper instars, with one actively molting. Ants like the one shown above tended to this small grouping of treehoppers. As I was choosing a photo to post, I noticed something strange about the treehoppers though. Do you see it too?

Look closely and you’ll see that a few nymphs have parasites. I wasn’t sure at first, so I started looking through my other photos. Sure enough, almost every one had one or more parasites. The parasites seem to prefer hiding under the wing pads and below the thorax.

Note the orange parasites hanging below the uppermost treehopper nymphs

See the parasites peeking out from beneath the wing pads of the lower nymph?

Most of the parasites were small, but there were at least a few plump ones.

Note large parasite on uppermost nymph

None of the photos provided a clear view of the parasites, but I suspect they are mites. In any case, apparently the services provided by the ants don’t include grooming.

Tapinoma Ant Observations

May 2nd, 2012 - 10:31 PM | Filed under Featured Photos | 1 Comment

April 13, 2012 | Twelvestones, Roswell, GA, USA

For several days I had noticed ants racing along the bricks at the base of one of my garage doors. I finally took a closer look to see what could be keeping them so busy for so long. They were streaming between a hole in my house and somewhere out in the front yard. I tried following, but these ants are tiny, only a few millimeters long. I quickly lost them in some pine straw.

Moving out

Turns out they were moving out of my house. The ones heading toward the yard were carrying eggs, larvae, and pupae. As I watched them though, I noticed something else leaving with them that didn’t look quite right.

That's not an ant

When I first saw one of the critters above, I knew it wasn’t an ant. My initial thought was it must have been a tiny roach. That first one was gone before I could react, but I headed inside to grab some containers in hopes of seeing more. Over the course of an hour and a half, I spotted three more and managed to grab a couple of them.

Watching one, it seemed unsure of its course. At times it would bump against some incoming ants and dart away. It would always rejoin the column, but sometimes moving in the wrong direction.

About to right itself

Eventually it would right itself, almost always after encountering an ant carrying a larva or pupa. I’d guess it can’t follow whatever chemical signals the ants are tracking and instead relies on following the cargo.

Follow the larvae

It got me wondering how the ants know which direction to go in. I know they follow a chemical trail, but what tells them which direction they should go? Actually, lots of questions came to mind as I watched them. How do they know it’s time to move? How do they decide on a new nest location?

Later, I gave the freeloaders the white paper treatment.

Dorsal view

I began to wonder if these weren’t crickets. I grabbed Arnett’s American Insects and started skimming the cricket families listed there. When I came to Myrmecophilidae (Ant-loving crickets), I figured that must be it. I briefly thought I might even be able to contribute something to BugGuide, but it turns out there were plenty of photos there already, confirming the identification.

Dorsolateral view

Both the specimens I captured have ovipositors and so must be female.

Frontal view

Rear view

Another shot

I found some good info on these in my Field Guide to Grasshoppers, Katydids, and Crickets of the United States. These crickets only live in ants nests. They apparently feed on oily secretions from the ants bodies, causing no ill effects. Only one species occurs in my area, the Eastern Ant Cricket, Myrmecophilus pergandei. This particular cricket species has been found living with eleven different species of ants.

Speaking of ant species, I decided to try and identify the host ants. Using the key in Ants of North America: A Guide to the Genera, I arrived at Tapinoma. Based on the remarks there, I believe these ants must be Tapinoma sessile. I sacrificed one to see how well the common name of Odorous House Ant applies. It was indeed odorous, and as I mentioned, they were leaving my house.

As I watched the ant column, one other thing caught my attention. Fairly often, I’d notice a much larger ant passing by, about twice as big as the others. I snatched one of those as well.

Queen

Remembering some of Alex Wild’s comments from his blog entry on how to identify queen ants, I recognized this as a queen. That only confused me though, since I had seen perhaps half of dozen of these in the brief time I observed the column. I naively thought that ant nests generally had a single queen. The wikipedia entry for this species says that its nests can actually have hundreds of queens!

I wasn’t familiar with either of these interesting insects when I started watching them. Had I encountered them a week later though, I’d probably have recognized them from a recent post from Alex Wild. He scooped me, but I couldn’t let the opportunity to blog about them pass.

What happened to the ants you might be wondering? Well, they can’t seem to make up their mind. As I write this there is still a column going strong, weeks later. They were steadily moving out for almost a week, but then at some point I noticed they had reversed course and were moving back in. I don’t want to imagine just how many thousands of ants there are somewhere in the walls of my home.

References:

American Insects:
A Handbook of the Insects of America North of Mexico

by Ross H. Arnett, Jr.
Field Guide to Grasshoppers, Katydids, and Crickets of the United States
by John L. Capinera, Ralph D. Scott, and Thomas J. Walker
Ants of North America:
A Guide to the Genera

by Brian L. Fisher and Stefan P. Cover

Dictyopharid Planthopper with Dryinid Wasp Parasite

April 18th, 2012 - 8:50 PM | Filed under Featured Photos | 1 Comment

~20mm | January 7, 2012 | Tupaciguara, Minas Gerais, Brazil

When I encountered the planthopper above, I had no idea what was going on. While not entirely sure, I assumed that might be a parasite on its abdomen. I had wanted to get a closeup of just the parasite, but when I went to grab the planthopper, it jumped and flew away with little difficulty. The parasite must not have been as much of a hindrance as it would appear.

Here’s a crop of the image above showing the parasite.

Closeup of parasite

It didn’t take much searching on the internet to determine that this must be the larva of a wasp in the family Dryinidae. There are plenty of images of larvae on BugGuide. According to Wikipedia, a larva initially feeds internally on the host. Only later in its development does it protrude the host as shown here.

I feel lucky to have seen this. As is usually the case, this just whets my appetite for more. Now I’ll be on the lookout for the odd looking adult.

More Ants and Scales

February 17th, 2012 - 5:45 PM | Filed under Featured Photos | 2 Comments

5mm long | July 8, 2011 | Victorio Siqueroli Park, Uberlandia, Minas Gerais, Brazil

Besides the turtle ants, there was one other type of ant crawling around in the same area. They were quite aggressive, often taking a threatening stance with their gaster turned down and under their body. The one above seems to be saying, “Back! This scale is mine”. The scale above, by the way, differs from the ones I posted about earlier.

Forager?

The ants above were fairly active. The one below, however, never moved from the spot I found it. While I assume it’s the same species, it has a slightly different body build. Note, for example, how much wider the head is. Maybe it’s a soldier?

Soldier?

Side view

Foraging Turtle Ants

February 15th, 2012 - 5:42 PM | Filed under Featured Photos | 1 Comment

4mm long | July 8, 2011 | Victorio Siqueroli Park, Uberlandia, Minas Gerais, Brazil

I spotted these turtle ants (Cephalotes sp.) crawling around on vegetation, occasionally stopping to solicit honeydew from scale insects. I’ve been somewhat enamored with these ants ever since seeing some of Alex Wild’s photos, particular the specialized nest guarding soldiers. Sadly, despite watching the workers, I’ve yet to successfully find a nest for an opportunity to photograph one.

I’ll have to satisfy myself with the foragers for now.

Dorsal view

Here’s another one taking honeydew from a scale insect.

Feeding from scale insect

Scale Insects

February 14th, 2012 - 5:55 PM | Filed under Featured Photos | 1 Comment

5mm long | July 8, 2011 | Victorio Siqueroli Park, Uberlandia, Minas Gerais, Brazil

I probably wouldn’t have noticed these scale insects were it not for the ants that would occasionally stop to feed from them.

Its difficult to see in the first photo, but each one has 20 or so waxy threads spiraling away from the body. It’s not clear to me where exactly they’re coming from. The threads are a bit easier to see in the next few photos.

Waxy corkscrew shaped filaments radiate out from the body

I wonder if the spirals don’t help the ants to locate the scale.

The scales excrete honeydew from a small orange tube (to the left above, right below).

Side view

Here’s what might be an immature form of these scale insects. The tube where honeydew is excreted is easier to spot here.

Immature scale? | ~2mm

And finally, here’s an ant soliciting honeydew from that same small scale.

Ant (~4mm) soliciting honeydew

I’ll separately post more photos of the ants.

Chalcid Wasp

January 25th, 2012 - 7:11 PM | Filed under Featured Photos | 1 Comment

5mm long | July 12, 2011 | Victorio Siqueroli Park, Uberlandia, Minas Gerais, Brazil

This is the first time I can recall encountering one of these wasps in the field. Chalcid wasps are easily recognized by their enlarged hind femora.

If you missed the one that emerged from a chrysalis I collected, check out this earlier post.

Parasitic Wasp Cocoon

January 24th, 2012 - 9:48 PM | Filed under Featured Photos | 3 Comments

6mm long | July 8, 2011 | Victorio Siqueroli Park, Uberlandia, Minas Gerais, Brazil

These attractively patterned little cocoons seem to be a common sight no matter where I travel. Each one holds the pupa of a parasitic wasp. I’ll often find what’s left of a caterpillar host nearby. The ones I notice are usually suspended by a thread, as here. That’s not always the case though.