black imported fire ant
Solenopsis richteri Forel


Solenopsis richteri is native to South America. The genus, Solenopsis, includes both the red and the black fire ant. Both are known for their aggressive nature and painful sting. The sting usually causes a pustule and can cause an anaphylactic reaction, even death, in some people. They are both a major pest both in agriculture and in urban settings, with damage costs running into millions of dollars.
Life Cycle
Solenopsis richteri undergo complete metamorphosis. A mature queen under good conditions can lay as many as 800 eggs each day. After hatching the larvae develop for about 6 to 10 days and then they pupate. After one to two weeks, pupation ends and they emerge as adults. Workers are wingless, sterile females and usually live for about a month to five weeks, sometimes more. A colony can contain from 100,000 to 500,000 workers. They defend the nest from attacks, feed the queen, and forage and care for the developing brood. The brood is made up of light colored eggs, larvae, and pupae. The winged reproductive ants live in the mound until their mating flight. Flights often occur in the spring and fall. Males die soon after mating. The fertilized queen has to find a suitable nest site, shed her wings, and begin digging a chamber in order to start a new colony. S. richteri queens can live for 7 years or more.
Solenopsis richteri has been introduced to North America and has become established in parts of the southeast. This species may be found in agricultural areas, range or grasslands, ruderal or disturbed, scrub or shrublands, and urban areas. S. richteri seems to have more cold tolerance than Solenopsis invicta and tends to be seen established further north. These two species can hybridize in regions where their populations intersect.
Control Efforts
Countries such as New Zealand have set up screening procedures for Solenopsis richteri to reduce the risk of accidental introduction of this pest into their country.


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