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In the previous posts about the silverfish and the rove beetles, I mentioned that I found the insects in native fire ant nests. The native fire ant that is extremely common in Arizona is the southern fire ant, Solenopsis xyloni.

Like other fire ants, the southern fire ant has a clubbed antenna and two nodes in its petiole. As with many southwestern ants, it seems to be highly variable in color. Our local species are dark brown, although the major workers have some lighter red-brown, usually on the head.


Photo by Michael Branstetter / © AntWeb.orgCC-BY-SA-3.0

As you can see from this photograph, Solenopsis xyloni does have a sting.

Fire ant workers exhibit a range of sizes.


They make distinct and heavily followed trails to certain foods.


These are consuming old cat food.


I noticed the soldiers often vibrate their gasters up and down while feeding.

I'm sure you will see more about this common species in future posts.

You never know what you are going to find under a rock. A group of children and I were flipping rocks, when I spotted a lone queen ant. I picked it up, thinking I would show it to the children under the microscope. Under closer inspection, it turned out to be a bit of a surprise.


I knew it was a native fire ant queen, genus Solenopsis. The clubbed antennae are easy to see. Without really looking at it, I figured it was probably Solenopsis xyloni, a common species here.

A closer look, however, let me know this was a less common fire ant.


If the lighting was better, you could see it is a golden butterscotch color, more like the first photograph.

It is possible the queen is the golden fire ant, Solenopsis aurea, but I think it is Solenopsis amblychila.

In any case, it is a new discovery for me. I couldn't find out much about the species. Have you ever seen them?

Taking kids outdoors to explore nature often pays off in more ways than you'd expect.

While looking up information on the hairy wood ants, Formica lugubris, I found out about some tiny ants called guest ants that also live in the wood ants' towering mounds. The shining guest ant, Formicoxenus nitidulus, forms a small nest within the bigger nest. As you can see from the photo below, they are called shining because of their reflective, shiny exoskeleton.

The shining guest ant workers are thought to pick up or steal food from their hosts, which are remarkably tolerant of this behavior. When a worker wood ant does attack a shiny guest ant, it usually gives up quickly. Researchers Martin, Jenner and Drijfhout think this is because shiny guest ants smell/taste bad.

Imagine guests that steal your food, take advantage of your security system, and are covered with an unpleasant substance. At least they are cute.

Photo by April Nobile / © / downloaded from Wikimedia Commons

Seriously, ant mounds house a variety of creatures. With the existence of hairy wood ants threatened, the guests become endangered right along with their ant hosts.


Martin, S. J., E. A. Jenner and F.P. Drijfhout. 2007. Chemical deterrent enables a socially parasitic ant to invade multiple hosts. Proc. R. Soc. B 7  vol. 274 (1626): 2717-2722.

For additional photos including a size comparison, see
The Highland Biological Recording Group

Foresters are set to log the ancient Holystone Forest, in Northumberland, England. But first they need to locate and save a few homes located in the forest. Are these structures human dwellings? No, they are giant ant mounds.

The northern, or hairy wood ants  (Formica lugubris) build towering mounds out of pine needles, from three to seven feet tall. The nests act as solar collectors and heaters, allowing wood ants to live in places too cold for most other ants. In addition, the large black and red workers sometimes bask in the sun to warm up and then move underground to act as living heat radiators.

Smaller wood ant mound from Switzerland

The hairy wood ants that build the mounds are now endangered, and every effort is being to made to protect them. Naturalists located of 69 mounds, which they mapped and gave GPS coordinates. Hopefully, the maps will help the loggers avoid getting too close.

For photographs and more information, see: has a story: Giant ants' nests given special building protection

York Dales Country News story:  GPS used to protect ant 'skyscrapers'

For photos and more information, see BBC - Potter ponders giant anthill

Edit:  And for children, see The Ant's Nest book review at Simply Science.