What species of ant is this? It's a large species of ant that ive only seen a handful of times where i live in southern california. Theres a berry from a juniper next to the ant which makes it a little easier to understand how big it is.

Dear Anthony,

Thank you for contacting AntBlog. Since you live in California, we asked Dr. Phil Ward, who is the curator for the AntWeb California Ants page to identify your ant. Here is what he had to say:

"This is an ant in the genus Camponotus, possibly Camponotus sansabeanus or C. semitestaceus (both common species in the drier parts of southern California). This individual is a dealate (or de-winged) queen. It is likely that she recently engaged in a mating flight, after which she dispersed some distance, landed on the ground, and discarded her wings. Unencumbered by wings she would now be searching for a nest site--under a stone or log, or directly in the soil--to start a new colony.

This method of independent colony foundation by a single queen is common in ants (you can read more about this here). In the case of Camponotus the queen sequesters herself in a cavity and begins to lay eggs. When these eggs hatch the queen feeds the larvae with regurgitated liquid food derived from the breakdown of her flight muscles. The larvae develop on this rather meager diet, eventually pupating and finally emerging as tiny adult workers, who open up the nest and begin to forage for food externally. Now the colony starts to acquire food resources from outside the nest cavity and it has the potential to grow rapidly. If it is successful (many incipient colonies fail) then in several years the colony will reach sufficient size to produce new sexual forms (queens and males) and the cycle continues."

You can also read several related posts here, here, and here.

Phil Ward (guest expert), Corrie Moreau, & the AntAsk Team

Dear AntAsk,

I am growing Rubiaceous ant-plants (Myrmecodias and Hydnophytums) in a greenhouse in Michigan. The ants in the 3 photos attached here have moved into some of the Myremcodia plants.

The ants are 2 mm long. The are a reddish-tan color except for a black abdomen, black eyes and black clubs on the end of the antenna.

The photos are not too good. The lines in the photos are mm lines on a ruler

Thanks for your help.

Frank

Dear Frank,

Thanks for the question! Luckily, this genus of ants, Cardiocondyla, have some very distinctive characteristics, especially when top and side views are available. The post-petiole (the second segment of the "waist" of an ant) is always much wider and at least a little shorter and more shallow than the petiole (first segment of the "waist"). This character alone is usually enough to identify them. Another feature every member of this genus that I am aware of shares is the matte texture of the head and much of the thorax (for myrmecologists using a microscope: the dorsal surface of the head, petiole, post-petiole, and often much of the dorsal and lateral alitrunk is pocked with evenly spaced, shallow fovea, yielding what appears to be a fine punctate sculpturing under low magnification). As a general rule, one should not use texture as a character to identify ant genera, but I know of no Cardiocondyla that are smooth-headed, or have groves or wavy lines like some ants (compare an average Cardiocondyla with a Tetramorium or Diacamma).

With regards to the species, one of the most common and widespread species is Cardiocondyla emeryi. This species has been reported from many latitudes on every continent and many tropical islands around the world. A very nice representation of some of these localities is given on its species page on AntWeb (linked above). Another common, widespread species is Cardiocondyla obscurior.

More information on Cardiocondyla and its species can be found in Seifert's very thorough revision from 2003 ( linked here). As Seifert notes, the genus has many species that cannot be easily distinguished with a microscope, and C. emeryi itself has such a wide range and is so variable that many would not be surprised if it turned out to actually be multiple species. Because there seems to be almost as much variation within some of these species as there is between them (I think no one could have done a better job with this group than Seifert, but it does make me a little bit suspicious that he had to use mathematical formulae to make sense of his morphological measurements...), the last word may not have been written about the species limits even of the most familiar members of this genus. I encourage you to read more about the fascinating behavior and reproductive strategies of these ants (an excellent overview in the introduction of the Seifert 2003 article linked above). Perhaps we'll have to do another blog post some day on the fascinating biology of Cardiocondyla!

I hope this helps!
Best,
Jesse Czekanski-Moir & the AntAsk Team

Hi there,

I'm doing a project for my comparative psychology class on ants. I'd like to see if ants are more attracted to more natural foods, such as other insects and fruits, or artificially flavored snacks, like we all have in our pantry. My instructor thought it would be a good idea to find out if ants are attracted to more natural or artificial odors. What do you think?

Whitney

Hi Whitney!

Testing the food preferences of ants sounds like a great idea! And it is definitely interesting to see whether ants prefer natural or artificially flavored foods. We have written two previous post (here and here) that might give you some ideas on how to design your experiment.

One thing you should keep in mind: When you test some natural food (e.g. a piece of banana) against some artificially flavored food (e.g. Cheetos), you will just be able to make the conclusion "Ants prefer the bananas over the Cheetos" (or vice versa), but you have no proof that it is due to the artificial flavor. It could be due to something else. You can still summarize your findings - ants might have preferred different artificial food items 10 times and the different natural food items only 2 times - and suggest that this might be due to the artificial flavor. But you would have no definite causal explanation as you don't have a real good control (this would be, for example, an artificial banana vs. a natural banana).

Basically, there are two set-ups for offering different foods to ants: binary choice experiments (where you offer 2 different food items simultaneously) or cafeteria style experiments (multiple choice experiments, where you offer several different food items simultaneously). You can either test several ants at the same time or test each ant individually. You should always test the ants' preferences at the same time (e.g. 5 min after you first offered the food) and testing at around the same time of day would be a good idea. To avoid position effects, you should alter the order of the food items offered after each round of experiments.

I hope this helps and please let us know if you have any additional questions!

Steffi Kautz & the AntAsk Team

What is the geographic range of leaf cutter ants (Atta spp) in the United States? Are there any known colonies of these (or other) fungus growing ants north of the Gulf States (in the Eastern US)?

Dear Don,

You may be surprised to know that leaf-cutter ants can be found in the United States! Although mostly a Neotropical group, both true leaf-cutters and the other fungus-growing attine ants can be found from South American through North America. There are ~230 described species of attine (fungus-growing) ants. In fact, attine ants are the world's first farmers and have been growing their fungal food crops for around 50 million years.

Here are the geographic distributions of the two true leaf-cutter ant genera (Atta and Acromyrmex) from the Ant Genera of the World website:

Recent work by Ted Schultz and Sean Brady has greatly contributed to our understanding the evolutionary history and timing of fungus-growing and leaf-cutting in the Attini ants [Ted R. Schultz & Sean G. Brady (2008) "Major evolutionary transitions in ant agriculture" PNAS 105 (14): 5435-5440.] You can read a nice review of the findings of this study on Myrmecos Blog here.

If you are interested in the geographic distributions of ants, I highly recommend checking out the Ant Genera of the World website.

Best regards,
Corrie Moreau & the AntAsk Team

Recently, I was bitten by this particular ant on one of my toes and I found the pain was extremely excruciating. The pain was not the typical type of ant bite and my toe did bleed because of the bite. The characteristic was when I brushed off the ant from my feet, the head of the ant was still sticking to my toe while it has been separated from the body. I would like to know what is the exact scientific name for this ant. This ant is found in West Malaysia when i was in region of Seremban. Hopefully you would be able to shed some light on this ant. Thank you

Regards, Azman

Dear Azman,

Thank you very much for contacting us at AntAsk and for providing this great picture! From the picture, it becomes clear that you actually got bitten by a termite, not an ant. Many different types of organisms mimic ants and we have a post on ant mimics here. A particular post that helps to tell apart ants from termites (termites are sometimes confused with ants) is found here.

To tell which species of termite bit you, we contacted a termite expert, Brian Forschler. Here is what he had to say:

"That 'ant' is most likely the termite Macrotermes carbonarius. The big-headed ones are the soldiers that would have been responsible for the bite. They are a species that builds mounds for their nest site and they can, not too often, forage above ground (they usually tunnel through the soil in search of food). The above ground foraging is a bit of an odd phenomenon that is part of a study being conducted at Universiti Sains Malaysia under Dr. Chow-Yang Lee. You might ask Azam to contact him for more details."

Brian Forschler (Guest Expert), Steffi Kautz & the AntAsk Team

I live in Ipswich, Queensland, Australia and have black with white stripe ants all over my verandah. I have never ever seen one of this type until about 6 months ago at my home. Visitors to my home are always suprised as they have never seen that type before either. They are larger then a green ant, but not as big as a bull ant. They walk side by side with the common black ant and are not agressive to my family or to other ants. I do not know what their nest looks like as I have never found it. I have looked at many other web sites in my quest to identify them, but with no success. I am hoping you can help me identify them please. Thanking you.

Dear Pamula,

Unfortunately without a image of the mystery ants it is very difficult to identify them. I am glad to hear that they are not aggressive to you or your family. Here are a couple of websites that may help with identification:

Ants Down Under
Ants of Brisbane

If you are not able to figure out what they are from the websites, you may want to contact an entomologist at a nearby natural history museum.

Best of luck,
Corrie Moreau & the AntAsk Team

Dear AntAsk,

I am in my final year of Dutch Preparotory University Edication and I am writing a script about the senses of the Lasius niger. I am not able to find the answer to the following question: What kind of chemical receptors does the Lasius niger have in his antennae? What kind of chemical substances can they smell?

Appreciatively,
Laura Carrière

Dear Laura,
Very little is known about the chemical receptors of Lasius in particular, but more is known about ants in general (most of the research has been done in carpenter ants (Camponotus) and wood ants (Formica), more recently also in leafcutting ants (Atta). It is likely that Lasius species are similar to Camponotus or Formica species regarding their chemosensory receptors. I would assume that they differ more in the number of sensilla than in the actual chemical compounds that they can perceive.

Ants have many receptors for different odorants (scents) in their antennae, but they also have receptors for sugar and other substances that you would call tastants in humans (substances that elicit a taste feeling, like sweet, sour, bitter or salty). In addition, ants can perceive carbon dioxide, humidity, temperature as well as touch with their antennae.

The majority of receptors on an ant antenna are odor receptors, ant ants have very high numbers of different odor receptors, so they can discriminate many different odors, perhaps more than any other insect that has been studied in this respect. So you could say that ants are the smell experts among the insects.

The biological reason for this is that ant workers mainly live on the ground and rely heavily on their sense of smell, whereas most other insects can fly and depend more on vision. You might say that ants sniff their way around and their 'view' of the world is probably mainly based on smells (unlike humans - we are mostly visual).

Another reason is that ants use many different kinds of pheromones - many more than other insects (you may consider reading more about pheromones). These pheromones are also perceived by odor receptors on the ants' antennae, just like 'ordinary' odors. Other pheromones sit directly on the cuticle of ants and they "taste" them when they touch each other with their antennae. While you know other people mainly by the way they look, ants know how their nest-mates 'taste' or smell. Ant brains are well equipped to process all this chemosensory information, but they do not process much visual information (except in some species with particularly large eyes).

Good luck with your essay on Lasius niger!

Wulfila Gronenberg (Guest Expert) & the AntAsk Team

Dear AntAsk
It seems like ants would be a great model organism for the study of the genetics of social behavior. Are there any efforts in this field, and if so what species of the ones currently being sequenced are regarded as the most likely to be used for these purposes?
Thanks
mikel

Dear Mikel,

You are correct that ants are certainly a good group to study questions regarding the genetics of social behavior (among many other questions). There is an effort to sequence ant genomes and as of today (February 2011) there are six ant genomes available (with several others in the pipeline). The six ant genomes that have been sequenced to date are:

- Atta cephalotes
- Camponotus floridanus
- Harpegnathos saltator
- Linepithema humile
- Pogonomyrmex barbatus
- Solenopsis invitca

For more information and links to the genomic sequences, please visit www.antgenomics.org.

Best,
Corrie Moreau & the AntAsk Team

Dear AntAsk:

My sister lives in St. Thomas, USVI. She writes the following:
"I have ants sometimes walking across my sofa. Have you ever heard of two different sizes of ants working together? Mostly they are tiny, but there are quite a number, maybe 1 in 10, which are about 3 times as large. They don't act like they're on different teams, and they seem to lug crumbs along the floor together. Never seen such a thing."
Neither have I. Any thoughts?
Thanks.
Owen

Dear Owen (and Owen's sister),

Thanks for your question. What you're seeing is most likely an ant in the genus Pheidole. Pheidole megacephala is probably the most common ant seen in people's houses that has two distinct sizes (such ants are referred to as dimorphic). The larger workers, sometimes called "majors" or "soldiers" have huge heads, and usually stay in the nest, but will come out to help the smaller workers when a particularly delicious (high in protein and/or fat) source of food is discovered.

There are several groups of ants whose workers come in more than one size, or caste. Ants have workers that are continuously variable in size (like carpenter ants, genus Camponotus, and Solenopsis invicta, the Red Imported Fire Ant) , or have more than two castes (like many leaf-cutter ants, especially in the genera Atta and Acromyrmex ). Such ants are referred to as polymorphic.

I hope this helps!
Jesse Czekanski-Moir & the AntAsk Team

Hi there,
I am in the planning stages of a new ant farm. I will attempt a 2' x 6' x 1" gelatin substrate farm. Similar to the Uncle Milton farm, including the fancy led lights, only larger and wall mounted.
I will also include at least 1 divider in order to sustain 2 colonies simultaneously. My question is; based on the dimensions, I will have a total of 1 cubic foot of substrate. How many ants can a farm of this size sustain?
If I include the divider and thus provide 0.5 cubic feet per colony, how large can these colonies get? Will they be cramped over a short time? Or will I end up with a lot of unused area?

Any insight would be appreciated. Of course any other tips would be great also.

Thank you,
Travis

Travis,

It is always good to hear that people are interested in keeping ants! And you seem to be planning to do it on a very large scale. We have addressed other questions regarding building very large ant farms here and on keeping ants here, here, and here.

As for how many ants your ant farm will hold, that will depend on which ant species you decide to populate your farm with. I did speak with a colleague who has quite a bit of experience with this (thanks Michael!) and he suggested that if you put the standard harvester ants that come with most ant farms "it would seem 600 ants over all would do well or 300 per section".

Good luck with your ant farm!
Corrie Moreau & the AntAsk Team