Okay, so it was only one fast-moving soldier.

You just can’t mistake the huge head of Pheidole soldiers. That’s why the common name is “big-headed ant.”

I tried to follow it, but never did find the nest. It was neat to spot it because I have seen them regularly at [...]]]> Yesterday I finally saw a Pheidole ant in Phoenix.

Okay, so it was only one fast-moving soldier.

You just can’t mistake the huge head of Pheidole soldiers. That’s why the common name is “big-headed ant.”

I tried to follow it, but never did find the nest. It was neat to spot it because I have seen them regularly at higher elevations, but not often here in the low desert.

Although it is easy to identify big-headed ants to genus if you find a soldier, figuring out the species is much more difficult. Antweb lists some 50 species of Pheidole in Arizona, some of which are not named.

With time and an unlimited budget, I might pick up E.O. Wilson’s Pheidole in the New World: A Dominant, Hyperdiverse Ant Genus to learn more.

Have you seen a copy of the book? What do you think of it?

First, I came across this harvester ant nest with dead ants, about half of which are light-colored callows. No live ants to be seen.

A nearby entrance hole had a lot more activity. The workers are actively grabbing each other.

By the way, the [...]]]> Although I confidently say they are raids in the title, let’s see the evidence:

First, I came across this harvester ant nest with dead ants, about half of which are light-colored callows. No live ants to be seen.

A nearby entrance hole had a lot more activity. The workers are actively grabbing each other.

By the way, the seed was going out, not in.

From out of the nest came workers carrying callows.

Here’s another one.

Up out of the nest…

… and off it goes.

This one is carrying a worker.

After a short while, the excitement died down a bit.

When Pogonomyrmex raid weaker colonies they are known to carry off larvae and pupae. I didn’t see any of that, but I couldn’t watch that long, either. We were at a park and kids were playing.

What do you think? Was it a raid?

In another note, James asked about the color of the silverfish.

It appears to be creamy-silvery in color. It didn’t stay outside for long though. It zipped out and zipped back in. The quality of the photograph leaves a tad bit to be desired.

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 [...]]]> 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.

The idea is to go outside, flip over a few rocks, and record what you see. The resulting posts will be published at Wanderin’ Weeta.

After looking under a couple of rocks, I posted about most of the creatures I discovered (including a very cool case-bearing [...]]]> Did you know that today is International Rock Flipping Day?

The idea is to go outside, flip over a few rocks, and record what you see. The resulting posts will be published at Wanderin’ Weeta.

After looking under a couple of rocks, I posted about most of the creatures I discovered (including a very cool case-bearing larvae) at Growing With Science. Of course flipping rocks is a fabulous way to find ants (and “experience” ants in other ways, too), so let’s take a look at what ants were hiding under rocks today.

The area I chose has mowed grass with a brick edging around it, as well as some rocks piled up in a drainage ditch. It isn’t uncommon to see Forelius running along the edging, so it was no surprise to find a few under the rocks as well.

Southern fire ants were in full force, too.

I was surprised how much more red these show that the ones in my yard a football field-length away.

I managed to get stung while taking this photograph. (Flipping rocks does has its hazards.)

Of course, Dolichoderinae don’t sting.

But they are more than willing to bite.

At least it was sitting still, so it is in focus

Did you participate in International Rock Flipping Day? What did you find?

Species 5 is Acromyrmex versicolor, and this worker was carrying a very large piece of caterpillar frass. As I noted in the comment, the frass is most likely from a Manduca rustica caterpillar, as there was a host tree nearby.

Júlio came up with the correct answer to the questions in the last post.

Species 5 is Acromyrmex versicolor, and this worker was carrying a very large piece of caterpillar frass. As I noted in the comment, the frass is most likely from a Manduca rustica caterpillar, as there was a host tree nearby.

(I apologize for the quality of the photograph. I was lying flat on my stomach on the sidewalk in a very public place while this ant was moving rapidly along.)

Júlio also wondered about an Acromyrmex versicolor worker carrying frass, which is something other leafcutters like Mycocepurus or Cyphomyrmex or even Trachymyrmex are more like to do.

I did locate the nest entrance. The workers were variable in size, showing different castes.

They appeared to have three pairs of spines on the mesosoma.

The workers were definitely collecting plant material. So, I think it is safe to say these ants were Acromyrmex versicolor.

And there’s a Dorymyrmex making an appearance.

As for the ant-finding challenge, I thought I did pretty well to find honeypot ants and leafcutters within two hours, but then again it is pretty easy to find cool ants in Tucson.

Summary:

I found a total of eight different ant species, less than the expert at the Tucson airport, but still a lot of fun.

Crematogaster opuntiae

Forelius, probably mccooki

Brachymyrmex patagonicus

Myrmecocystus placodops

Acrimyrmex versicolor

Solenopsis xyloni

Dorymyrmex sp.

plus one species I, gulp, could not identify and the photographs are not a help.

I know I could have found more if I could have flipped rocks or tore into trees, but this was a public place with prohibitions on that sort of thing. Surprisingly, there were no harvester ants in the list. I’m not sure why not, because I find them quite often in other places.

So, what do you think about Acromyrmex carrying caterpillar frass? Is that common behavior or not?

Species 5:  You tell me.

To make this a little more fun, why don’t you tell me what the fifth species is.

Bonus:  What is this ant carrying?

Species 4. Myrmecocystus placodops

In addition to the usual suspects, Tuscon has quite a few interesting species.

What are those peeking out of a hole?

Taking a closer look, I found worker ants with black bodies, red heads and long [...]]]> The challenge: to see how many species of ants I could find in Tucson, Arizona in two hours.

Species 4. Myrmecocystus placodops

In addition to the usual suspects, Tuscon has quite a few interesting species.

What are those peeking out of a hole?

Taking a closer look, I found worker ants with black bodies, red heads and long antennae.

The workers were milling about at the nest entrance, aware of my presence.

These are Myrmecocystus placodops, a type of honeypot ant.

Honeypot ants are the camels of the ant family. They live in dry areas throughout the world where food and water may be scarce for long periods of time. To cope, honeypot ants have unique storage tanks for holding liquids. These storage tanks are special large individual worker ants called repletes.

When times are good and food is abundant, the repletes store any extra liquid food that is available and swell up like balloons. Then they hang around, literally, from the ceiling of the nest, until times are tough. If the colony runs out of food, the other workers entice the repletes to spit up their reserves to share with the others.

Honeypot ants have deep nests. Mammal predators, such as badgers, are known to dig the nests open in search of the repletes.

Watching these, I had to wonder about the red heads. Remember the stories about the parasitic nematode that causes an ant’s gaster to swell up like a red berry to make it enticing to birds (see National Geographic’s version)? Looking at those photographs reminded me of a reverse of these ants, which have bright heads instead.

Have you ever encountered Myrmecocystus placodops?
What do you think of those red heads?

Species 2. Forelius

Most likely they are Forelius mcccooki, the species I have identified in Phoenix, but because this was a public place I didn’t take samples.

Chris Schmidt indicates that Forelius are probably the ants you are most [...]]]> The challenge: to see how many species of ants I could find in Tucson, Arizona in two hours.

Species 2. Forelius

Most likely they are Forelius mcccooki, the species I have identified in Phoenix, but because this was a public place I didn’t take samples.

Chris Schmidt indicates that Forelius are probably the ants you are most likely to stumble upon in Tucson (Backyard Ants of Tucson).

Forelius are always easy to spot because they are active even during the hottest parts of the day and they forage in long trails along sidewalks or up trees.

I had to laugh at what I found next.

Do you remember the person who fed colored water to ants to make them turn the colors of the rainbow? (Alex Wild shows a photograph by Maxim Piessen that uses the same technique.)

Now nature imitates art.

The color was provided by…

a prickly pear cactus fruit with help from this gal.

Do Forelius ants occur where you live? What color are they?

Last week I received the kit in the mail.

Each kit comes with four vials with blue caps, four vials with red caps and one large tube with an orange cap. The red and blue-capped vials come [...]]]> You might recall that School of Ants is a citizen science program based at North Carolina State University (earlier post).

Last week I received the kit in the mail.

Each kit comes with four vials with blue caps, four vials with red caps and one large tube with an orange cap. The red and blue-capped vials come baited with cookie crumbs and are to be placed in specific setting. The orange-capped tube is for anything else you would like to have identified.

The next day I placed the open vials outside as directed.

The southern fire ants were happy to cooperate and soon were carting away bait.

I thought this was a perfect opportunity to learn more about ant ecology.

Ecologists who study interference competition often use baits. They recognize three strategies used by ants in finding and taking baits:

• Opportunists- able to find baits quickly, but don’t defend it
• Extirpators- may take longer to find bait, but recruit higher numbers and defend the bait (often have soldier caste)
• Insinuators – ant species that are too small in size and number to be noticed by extirpators

In this case the southern fire ants found the baits quickly, and were also defending. They definitely fit the definition of extirpators.

What about the tiny rover ants that are also found in the yard? Are they small enough to be insinuators?

Notice the rover on the top of the vial? Those are fire ants on the rim.

Will the defender ignore the rover ant?

No, the defender fire ant charges the rover ant and chases it away.

Let’s take a look in another tube.

Once again the rover ant approaches from the top.

Along comes the fire ant…

and chases it away.

In the end, the southern fire ants were able to dominate the baits. Looks like rover ants are opportunists rather than insinuators, in spite of their small size and lower numbers.

The bottom line is that baited vials are definitely useful for learning more about the ants in your area.

I would recommend this project. You do need to provide an envelope and postage to send the vials back, but otherwise time is the main investment. If you decide to take part in School of Ants, I’d love to hear what you find out.

Reference:  Parr, C. L. and H. Gibb. Competition and the Role of Dominant Ants, Chapter 5. In: Lach, L. Parr, C.L. and K.L. Abbott., eds. 2010. Ant Ecology. Oxford University Press, Oxford.