Forelius Ant
Forelius pruinosus
Observed at the growing point of a Saguaro Cactus (Carnegiea gigantea) near Bumble Bee, Yavapai Co., Arizona, USA. June 2012.
Formicidae -- Ant Family
These are ubiquitous ants in the
Sonoran Desert, but are only to be seen when the weather is very warm to hot.
They generally do not emerge from their colonies to forage before temperatures
exceed 25°C. Small, less than 3mm, and very fast moving, they follow tight
columns from their colonies into trees and shrubs where they prey on small
insects and seek sugary substances.
Trees, shrubs and cactus in the Sonoran Desert form a vital alliance with these ants. Growing points of plants such as new growth, buds, flowers and fruit are tender and full of moisture and nutrients. They are thus vulnerable to plant-chewing animals of all sizes. By releasing small quantities of sugar and other substances, the plants draw in several kinds of ants, but especially F. pruinosus. The ants protect the offered sweets from all comers by use of noxious gas. Tap one of the ants under your fingers and smell! Whew. Very strong repellant indeed. In this way the plant's expensive new investments are protected through a small contribution of carbohydrate.
More Information:
- Bugguide.net Univ. of Iowa
- Ants of the Southwest
- Google Images
- Google Scholar Literature Search
- Book Reference: Venomous Animals of Arizona by Robert Smith (who was one of my profs at U.A.) available at Abe Books.