|Fritz, Gary - EASTERN ILLINOIS UNIV|
|VANDER MEER, ROBERT|
Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 15, 2002
Publication Date: June 1, 2003
Citation: FRITZ, G.N., VANDER MEER, R.K. SYMPATRY OF POLYGYNE AND MONOGYNE COLONIES OF THE FIRE ANT, SOLENOPSIS INVICTA (HYMENOPTERA: FORMICIDAE). ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA. 2003. v. 96(1). p. 86-92. Interpretive Summary: Red imported fire ant colonies with multiple queens were thought to occur in discrete populations along with discrete populations of the single queen form of the ant. A better understanding of single and multiple queen populations and how they interact is important because the multiple queen form is thought to be more difficult to control and both population types have been shown to differentially susceptable to currently used biocontrol agents. A scientist at the Center for Medical, Agricultural, and Veterinary Entomology, Gainesville, FL and a colleague at Department of Biological Sciences, Eastern Illinois University have determined that a previously identified multiple queen population in north Florida is actually interspersed with the single queen form. This unexpected result better conforms to current genetic-based hypotheses that require close proximity of the two forms for successful maintainence of multiple queen populations.
Technical Abstract: The polygyne form of the red imported fire ant, Solenopsis invicta, is thought to occur primarily in discrete populations embedded within areas composed of monogyne colonies. This distribution implies that polygyne colonies compete with monogyne colonies and subsequently create a population homogenous in social form. Because polygyne colonies produce mostly sterile males, opportunities for insemination of female alates migh be minimal at the centers of large polygyne areas. To test for homogenity in social form, a large polygyne population described in northcentral Florida was examined for the presence of single queen colonies. Up to 51 colonies were sampled from each of six sites located along an East-West transect through the middle of the polygyne area in Marion County and a site at the northernmost limit of the polygyne area, Gainesville, Florida. Several hundred workers from each nest were collected along with nest material. The social form of each sample was determined by an aggression test of workers to the introduction of non-nestmates and by the dissection of males for sterility. Both social forms of S. invicta were present at all collection sites and 103 of 333 (30.93%) colonies sampled were determined to be monogyne colonies. Among the collection sites, the percentage of colonies that were monogyne ranged from 3.9% to 57.4%. The polygyne region in northcentral Florida is more accurately described as an area where relatively high frequencies of polygyne colonies are interdispersed with single queen colonies.