Subfamily MYRMICINAE
Tribe FORMICOXENINI

Cardiocondyla minutior Forel 1899

Cardiocondyla minutior, full face view of a worker (click image to enlarge).
Photo courtesy of http://www.antweb.org/
Cardiocondyla minutior, full face view of a worker (click image to enlarge).
Photo courtesy of http://www.antweb.org/

 

Introduction
Cardiocondyla is an old world genus of omnivorous ants native to Africa and Asia.  This genus includes several common tramp species that have spread globally with human commerce.  Because of their small size, Cardiocondyla species are often overlooked.  Colonies of most species are small (<500 workers) and are typically located in soil, especially in disturbed, open habitats near rivers, roads, forest margins, or other similar areas (Seifert 2003).  However, some species also nest above ground in plant structures.  Members of this genus are not generally considered to be a pest species.

Identification
Cardiocondyla workers are small to medium in size (1.5 to 3.5 mm) and yellow to dark brown. The antenna is 11 or 12-segmented and terminates in a 3-segmented club. The clypeus is flattened with lateral portions projecting outward. The promesonotal suture is lacking. Propodeal spines may be distinct or absent. For their small size, workers have a relatively large sting. Pilosity is sparse to entirely absent on the dorsum of body.  In the southeastern United States, Temnothorax is the only genus that would be likely confused with Cardiocondyla.  Temnothorax species in this region differ by having distinct pilosity present on the dorsum of the body.  Cardiocondyla minutior can be differentiated from the other four species of Cardiocondyla reported from the southeastern United States by its dark brown coloration; metanotal groove not being impressed; antennal scapes not reaching occipital border by at least the width of the scape; elongate head; shiny petiole and postpetiole; and short, but spine-like propodeal spines.

According to Seifert (2003), specimens of this species from the US have been misidentified as C. nuda.

Original Description
Link to paper with original description by Forel: http://antbase.org/ants/publications/3966/3966.pdf

Biology and Economic Importance
Habitat/Nesting: Cardiocondyla minutior has been reported to nest in shallow soil in open, disturbed areas (Seifert, 2003).

Life Cycle: This species, similar to others in the genus, produces ergatoid males in addition to alate males. Ergatoid males are known to fight on another to the death for exclusive mating (Terayama, 1999).

Native Range: IndoMalaysia, Asia

Distribution
Worldwide: Islands of the Indian Ocean, India, Sri Lanka, Nepal, Japan, Polynesia, Indonesia, New Guinea, Caribbean (Seifert, 2003).

United States: Alabama? (MacKay, 1995; identified as C. nuda, but likely C. minutior), Georgia? (Smith, 1979; identified as C. nuda, but likely C. minutior), Louisiana (Dash, 2005; identified as C. nuda, but likely C. minutior), and Florida (Seifert, 2003).

Literature Cited

Dash, S. T. 2005. Species Diversity and biogeography of Ants (Hymenoptera: Formicidae) in Louisiana, with Notes on their Ecology. M.S. Thesis, Louisiana State University, 290 pp.

MacKay, W. P. 1995. New distributional records for the ant genus Cardiocondyla in the New World (Hymenoptera: Formicidae). Pan-Pacific Entomologist 71: 169-172.

Seifert, B. 2003. The ant genus Cardiocondyla (Insecta: Hymenoptera: Formicidae) - a taxonomic revision of the C. elegans, C. bulgarica, C. batesii, C. nuda, C. shuckardi, C. stambuloffii, C. wroughtonii, C. emeryi, and C. minutior species groups. Ann. Naturhist. Mus. Wien. B. Bot. Zool. 104(B): 203-338.

Smith, D. R. 1979.  In Catalog of Hymenoptera in America north of Mexico. Smithsonian Institution Press, Washington D. C.  Vol. 2, pp. 1323-1427. 

Terayama, M. 1999. Taxonomic studies of the Japanese Formicidae, Part 6. Genus Cardiocondyla Emery. Memoirs of the Myrmecological Society of Japan. 1: 99-107.

Links

AntWeb Images
Identification Guide to the Invasive Ants of the Pacific Islands: Cardiocondyla minutior