Nylanderia terricola

School of Ants collection
Literature record

Nylanderia terricola

From Dr. Eleanor's Book of Common Ants

Species name: Nylanderia flavipes, N. terricola, N. fulva

A.K.A.: Crazy ants

Size: 0.07-0.1 inch

Where it lives: Nylanderia aren’t choosy about where to nest and can nest under trees or in your potted plants.

What it eats: Nuts for sugar, Nylanderia prefer sweet syrups produced by aphids, but will snack on human garbage or scavenge for insects if they get the chance.

What’s the big deal?

Crazy relatives. There’s one in every family. I have several in mine. Take Aunt Nee Nee, who brings my grandfather along to all our family events. My grandfather died 15 years ago. His ashes reside in a wooden box the size of two dictionaries stacked on top of each other. At my wedding, she propped him in the choir loft, “so he can see,” and had the photographer do a photo session with him. Or Uncle George, who went missing for two weeks, and just when everybody thought he was dead he came rolling into town in a pink Cadillac with a live monkey strapped in the passenger seat. Or Aunt Ann, who ... well, you get the picture.

Ants have a lot of crazy relatives, too. Most members of the genus Nylanderia even get the common name “crazy ant.” Some of them deserve it.

They even have crazy little hair-dos. If you’re like me and you have a special place in your heart for all things fuzzy, crazy ants are the ants for you. Ranging in color from pale yellow to black and about the size of a sesame seed, crazy ants have spiky hairs covering their entire bodies that make them look like baby birds or old men’s heads. Either way: a-dorable. They’ll nest in any nook or cranny they can find, squeezing into potting soil or snuggling up to trees in medians. They eat pretty much anything, too. From honeydew to small insects to our trash, crazy ants aren’t picky. Three species make the most common list: Nylanderia flavipes (the yellow-footed ant), Nylanderia terricola, and the ant equivalent of Aunt Annie Kate (the craziest): Nylanderia fulva (the Raspberry crazy ant).

Crazy ants get their common name from the way they run around like a house afire while they’re foraging. While most ants seem to move about in orderly lines or careful steps, crazy ants have a wiggle-waggle way of running as they go to and from food. Between their sparse fur coats and their zany walk, you shouldn’t have a hard time telling these nutty ants from the others running around your city park.

Their easygoing ways and catholic diets make crazy ants excellent party crashers. Because they can nest anywhere and eat anything, crazy ants have no problem moving into new environments. When animals like crazy ants aren’t fussy about what they need, they can expand their empires into new locations more easily than their choosier chums. Unfortunately, this means these easy-to-please insects make good invasive pests.

Yellow-footed ants originally come from Asia but have made themselves right at home across the eastern and midwestern United States. Once they move in, they gobble up all the food and make lots of babies, eventually taking resources from other ant species and amassing huge worker populations. By now, we all know that our native ants do many good deeds for our environment, from engineering the soil to keeping tree canopies healthy to planting our wild herb seeds. Suppose a crazy ant like a yellow-footed ant moved in and took all of the homesteads from our native ants or ate all their food? What would happen to our homegrown heroes? And what about the jobs they do? Many times, invasive species like yellow-footed ants spell trouble for our natural world.

But yellow-footed ants are just the tip of the iceberg of crazy in Nylanderia world. Raspberry crazy ants, named for the exterminator who discovered them, Tom Raspberry, take outrageous ant behavior to a whole new level.

Raspberry crazy ants originally come from Brazil and Argentina but made a homestead in Houston, Texas, a few years ago. Just like yellow-footed ants, they began to scarf down all the ant food they could find, turning that ant food into ant babies. Lots and lots of ant babies. In some places, Raspberry crazy ants became so numerous they overran human structures.

They can reach such huge populations they become more than a nuisance for humans; they become real trouble. Raspberry crazy ants, like their crazy ant cousins, nest in all kinds of crannies, and electrical boxes make perfect crannies for them. If a worker gets zapped in an electrical box, she’ll release a “Danger!” odor, called an alarm pheromone, which alerts her sisters that she’s in need of assistance. Her sisters will pour in en masse and flood the box, shorting out electrical equipment. The more that get zapped, the bigger the danger odor and the more ants pour in. It’s not unusual for people in the southwestern United States to open electrical boxes and find them packed with tens of thousands of electrocuted ants.

Crazy ants also get a case of the hangries. When these ladies get low on sugar, they become super aggressive and start swinging punches at anybody within reach. Like all Nylanderia, these bizarre trespassers can’t sting, but they build up such tremendous populations that when they come to town, they can even wipe out the ornery red imported fire ants.

While we might not always appreciate our crazy relatives (Uncle George’s monkey was a biter), they certainly do make our lives more interesting. Sometimes, they might take over the party. Even so, they’re fun to watch, and you can always count on them to show up.

Find out more about this species at Antweb and see more photos at Alex Wild's photography site .


Gotzek, D., Brady, S. G., Kallal, R. J. & LaPolla, J. S. 2012. The Importance of Using Multiple Approaches for Identifying Emerging Invasive Species: The Case of the Rasberry Crazy Ant in the United States. Plos One, 7, e45314. doi: 10.1371/journal.pone.0045314.

Horn, K. C., Eubanks, M. D. & Siemann, E. 2013. The Effect of Diet and Opponent Size on Aggressive Interactions Involving Caribbean Crazy Ants (Nylanderia fulva). Plos One, 8, e66912. doi: 10.1371/journal.pone.0066912.

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Ivanov, K. & Milligan, J. 2008. Paratrechina flavipes (Smith) (Hymenoptera : Formicidae), a new exotic ant for Ohio. Proceedings of the Entomological Society of Washington, 110, 439-444. doi: 10.4289/07-046.1.

Kallal, R. J. & Lapolla, J. S. 2012a. Monograph of Nylanderia (Hymenoptera: Formicidae) of the World, Part II: Nylanderia in the Nearctic. Zootaxa.

Kallal, R. J. & Lapolla, J. S. 2012b. Monograph of Nylanderia (Hymenoptera: Formicidae) of the World, Part II: Nylanderia in the Nearctic. Zootaxa.

Pecarevic, M., Danoff-Burg, J. & Dunn, R. R. 2010. Biodiversity on Broadway - Enigmatic Diversity of the Societies of Ants (Formicidae) on the Streets of New York City. Plos One, 5, e13222. doi: 10.1371/journal.pone.0013222.

Sharma, S., Oi, D. H. & Buss, E. A. 2013. Honeydew-Producing Hemipterans in Florida Associated with Nylanderia Fulva (Hymenoptera: Formicidae), an Invasive Crazy Ant. Florida Entomologist, 96, 538-547.

Wetterer, J. K. 2011. Worldwide Spread of the Yellow-Footed Ant, Nylanderia Flavipes (Hymenoptera: Formicidae). Florida Entomologist, 94, 582-587.