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Subfamily FORMICINAE
Tribe CAMPONOTINI

Camponotus (Tanaemyrmex) conspicuus inaequalis Roger, 1863
(status unclear: possibly
Camponotus (Tanaemyrmex) tortuganus Emery, 1865)

Author: Joe A. MacGown
Uploaded, 2009; last updated 7 April 2016

Introduction
Ants in the genus Camponotus are collectively known as carpenter ants because some species nest in wood, including man-made structure. This genus includes some of the largest and most common ants in the world, and they are found in all biogeographical regions (Bolton, 1995).  More than 900 species of Camponotus are known worldwide, with 50 species reported from the United States (Hanson and Klotz, 2005), and 20 species found east of the Mississippi River (Deyrup, 2003; Smith, 1979). 

Species in this genus are variable in size with workers ranging in size from 3.0 to 15 mm or more in length and queens (also referred to as females) of some species attaining a length of 19 mm or more. Many species are polymorphic. Workers have a 12-segmented antenna that lacks an apical club. Antennal fossae do not touch the posterior border of the clypeus. Ocelli are not present on the heads of workers. The workers of most species have an indistinct metanotal suture between the promesonotum and the propodeum, although this suture is present in C. sexguttatus and some members of the subgenus Colobopsis.  Those species that lack the obvious and deep metanotal suture have the shape of the alitrunk in a smoothly curved arc (as seen in profile). 

Camponotus conspicuus inaequalis is in the subgenus Tanaemyrmex, which differs from the other carpenter ant subgenera by having a median carina present on the clypeus. The status of this species is unclear. Historically, specimens of this species from the US have been identified as C. tortuganus, but after closer examination by Mark Deyrup (per. com. Mark Deyrup, Archbold Biological Station), noted that C. c. inaequalis. was also present in southern Florida.

Taxonomic History (Bolton 2016)
Camponotus inaequalis Roger, 1863: 147 (w.q.) CUBA. Neotropic.  Combination in Camponotus (Myrmoturba): Forel, 1914: 267; in Camponotus (Tanaemyrmex): Emery, 1925: 80. Material of the unavailable name Camponotus eburneus referred here by Wheeler, 1913: 503 (in text). Currently subspecies of Camponotus conspicuus: Forel, 1914: 267

The status of this species is unclear. In 1863, Roger described C. inaequalis from Cuba. Later, in 1895, Emery described C. maculatus tortuganus from a specimen collected by Pergande in the Dry Tortugas. Forel (1914) sunk C. inaequalis to a subspecies of C. conspicuuus. Wheeler (1923) raised C. tortuganus to species. From that point onward until 1988 (Deyrup et al. 1988), specimens collected in Florida were called C. tortuganus. However, Deyrup et al. (1988) discovered specimens in the Florida Keys whose striped coloration matched C. c. inaequalis. Specimens resembling typical C. tortuganus were also collected in the Keys. According to Deyrup (Pers. Comm.), numerous specimens with C. c. inaequalis and C. tortuganus-inaequalis coloration have been collected in Florida since approximately 1965. Wetterer and O'Hara (2002) stated that the holotype collected by Pergande was actually labeled as being from the Bahamas, rather than from the Dry Tortugas. Further, in the Wetterer and O'Hara (2002) publication, they stated that specimens identified from Florida as C. tortuganus were actually C. conspicuus zonatus Emery, 1894. This seems unlikely, as C. c. zonatus has a Central American distribution. Future genetic work could be useful in more definitive identifications of this group in the USA. Based on Deyrup's collections (Pers. Comm.), its seems likely that both C. tortuganus and C. c. inaequalis may be present in Florida and that these two species may be interbreeding forming a hybrid. Alternatively, C. tortuganus and C. c. inaequalis could actually represent variations of the same species, in which case the name C. c. inaequalis would have priority. Currently, we recognize both species as being present in Floridae.

It seems much more likely that specimens from Florida include both C. c. inaequalis and C. tortuganus and these two species sometimes hybridize, which would account the variable color forms or C. inaequalis and C. tortuganus represent one variable species, in which case the name C. c. inaequalis would have priority.

Identification

Workers of this species are similar to those of C. tortuganus but with stripes or notable spots on gaster; similar to C. socius Roger, but are much shinier in overall appearance.

Biology and Economic Importance
It is unclear whether or not C. c. inaequalis is a native or exotic species. In the US it has been reported from the southern half of Florida,. .

Distribution

Neotropical Region: Cuba (AntWeb data)

U.S. Distribution: Florida (Mark Deyrup, pers. comm.)

Acknowledgments
Thanks to Mark Deyrup (Archbold Biological Station) for his valuable input about this species. Funding for the ant work being done by the MEM in Alabama and Mississippi is from several sources including the National Institute of Food and Agriculture, United States Department of Agriculture, under Project No. MIS-012040, the Mississippi Agricultural and Forestry Experiment Station at Mississippi State University, with support from State Project MIS-311080, NSF Grants BSR-9024810 and DFB-9200856, the Tombigbee National Forest (U.S. Forest Service), the Noxubee Wildlife Refuge, Mississippi Natural Heritage Program Research Grant, USDA Forest Service Agreement No. 08-99-07-CCS-010, the William H. Cross Expedition Fund, and primarily by the USDA-ARS Areawide Management of Imported Fire Ant Project. Additionally, special cooperation has been provided by State Parks, National Forests, National Wildlife Refuges, the Natchez Trace Parkway, and from various private landowners in both Alabama and Mississippi.

Literature Cited
Bolton, B. 1995. A new general catalogue of the ants of the world. Harvard University Press: Cambridge, Massachusetts, USA.

Bolton, B. 2016.  Bolton World Catalog Ants. Available online: http://www.antweb.org/world.jsp. Accessed 9 March 2016.

Deyrup, M.  2003. An updated list of Florida ants (Hymenoptera: Formicidae). Florida Entomologist 86: 43-48. 

Deyrup, M., N. Carlin, J. Trager, and G. Umphrey. 1988. A review of the ants of the Florida Keys. Florida Entomologist 71: 163-176.

Deyrup, M., L. Davis, and S. Cover. 2000. Exotic ants in Florida. Transactions of the American Entomological Society 126: 293-325.

Emery, C. 1895. Beiträge zur Kenntniss der nordamerikanischen Ameisenfauna. (Schluss). Zoologische Jahrbücher. Abteilung für Systematik, Geographie und Biologie der Tiere 8:257-360.

Emery, C. 1925. Hymenoptera. Fam. Formicidae. Subfam. Formicinae. Genera Insectorum 183:1-302. 

Forel, A. 1914. Le genre Camponotus Mayr et les genres voisins. Revue Suisse de Zoologie 22:257-276.

Hansen, L. D., and J. H. Klotz. 2005.  Carpenter ants of the United States and Canada.  Cornell University Press.  Ithaca, N. Y.  i-xii+204 pp. 

Roger, J. 1863. Die neu aufgeführten Gattungen und Arten meines Formiciden-Verzeichnisses nebst Ergänzung einiger früher gegebenen Beschreibungen. Berliner Entomologische Zeitschrift 7:131-214.

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

Wetterer J. K. and O’Hara B. C. 2002. Ants (Hymenoptera: Formicidae) of the Dry Tortugas, the outermost Florida keys. Fla. Entomol. 85: 303–307.

Wheeler, W. M. 1910g. The North American ants of the genus Camponotus Mayr. Ann. N. Y. Acad. Sci. 20: 295-354.

Wheeler, W. M. 1913. The ants of Cuba. Bulletin of the Museum of Comparative Zoology 54:477-505. 

Links

AntCat
AntWeb