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Paratrechina longicornis (Latreille, 1802)
"longhorned crazy ant or longlegged crazy ant"

Uploaded 2009; last updated 24 August 2016
Authors: Joe A. MacGown and Ryan J. Whitehouse

Paratrechina longicornis, full face view of a worker(MS, Hancock Co.) (photo by Joe A. MacGown)
Paratrechina longicornis, lateral view of a worker(MS, Hancock Co.) (photo by Joe A. MacGown)
Paratrechina longicornis, dorsal view of a worker(MS, Hancock Co.) (photo by Joe A. MacGown)
Paratrechina longicornis, full face view of a queen (FL, Seminole Co.) (photo by Joe A. MacGown)
Paratrechina longicornis, lateral view of a queen (FL, Seminole Co.) (photo by Joe A. MacGown)
Paratrechina longicornis, dorsal view of a queen (FL, Seminole Co.) (photo by Joe A. MacGown)
Paratrechina longicornis, lateral view of a worker(MS, Jackson Co.) (photo by Joe A. MacGown)

The Paratrechina genus is probably best known from the widely distributed species Paratrechina longicornis. Most Paratrechina species seem to be focused around tropical Africa and Madagascar and can now be found all around the world’s tropical and semitropical areas. These ants are opportunistic foragers and can often be found invading homes in search of sugary food. In nature Paratrechina species are often found tending honeydew producing Hemiptera or drinking from plant nectaries.

Paratrechina species can be identified by having a waist with one distinct segment; acidopore at the apex of the gaster with a circular fringe of setae; 12-segmented antennae; triangular mandibles with five teeth; six-segmented maxillary palps; head and body with dorsally erect, coarse setae; very long scape and legs; and weakly shinning with scarce pubescence.

Paratrechina longicornis is the most widespread Paratrechina species is most often found in disturbed habitats and has a pantropical distribution. This species can be a common house pest foraging inside for any scraps of food lying around and has been able to spread to less tropical environments because of its close association with humans and heated buildings.

Taxonomic History (Bolton 2016)
Formica longicornis Latreille, 1802: 113 (w.) SENEGAL. Afrotropic. Jerdon, 1851: 124 (q.); André, 1881: 60 (m.); Hung, Imai & Kubota, 1972: 1024 (k.); Wheeler & Wheeler, 1986: 336 (l.); Fox, et al. 2007: 3 (l.); LaPolla, Hawkes & Fisher, 2013: 75 (w.). Combination in Prenolepis: Roger, 1863: 10; in Paratrechina (Nylanderia): Emery, 1910: 129; in Paratrechina: Wheeler, 1921: 112. Senior synonym of Paratrechina currens: Emery, 1892: 166; of Paratrechinagracilescens: Roger, 1863: 10; of Paratrechina vagans: Dalla Torre, 1893}: 179. Senior synonym of Paratrechina hagemanni: LaPolla, Brady & Shattuck, 2010: 128. See also: Mayr, 1865: 50; Forel, 1891: 81; Forel, 1894: 406; Emery, 1910: 129; Trager, 1984: 153; LaPolla, Hawkes & Fisher, 2013.

Worker: HL 0.67-0.72, HW0.49-0.51, SL 1.16-1.19, EL 0.19-0.21, MeSL 0.95-1.06 (n=5) (MEM specimens). Color is brown to dark brown with the gaster being slightly darker in color than the alitrunk in some specimens. Legs lighter in color than the body especially the tarsi. Overall ant is weakly shining with occasional bluish sheen. Head with many coarse, erect, light colored setae and a few appressed, hair-like setae present, especially anterior to the eyes; eyes distinctly convex and about 1/3 of the length of the head and located medially on the head; ocelli lacking; mandibles more or less triangular is shape with five distinct teeth; maxillary palps long and six-segmented; antennae 12-segmented with greatly elongated scape. Mesosoma with conspicuous, coarse, erect setae and sparse, appressed hair-like setae; dorsum of alitrunk relatively flat with a distinct declivity where the abdomen and thorax meet; legs greatly elongate, much longer than alitrunk. Waist single segmented; petiolar node relatively short with a flat anterior face and an anteriorly sloped posterior face. Gaster with posteriorly directed, coarse setae; bulbous in shape; small acidopore present at apex.

Queen: HL 1.06, HW 1.03, SL 1.40, EL 0.39, MeSL 1.92 (n=1) (MEM specimen). Color brown to dark brown with lighter specimens often with a yellowish mesonotum. Coxae, trochanter and base of femur pale yellow. Head covered in short, appressed, hair-like setae; eyes about 1/3 the length of the head and positioned posterior to the midline of the head; three ocelli present; mandibles more or less triangular is shape with five distinct teeth; maxillary palps long and six-segmented; antennae 12-segmented with elongate scape; scape not as long in comparison to the head as in workers. Mesosoma covered with a light pubescence; enlarged with four wings or wing scars present. Waist single segmented; petiolar node short in comparison to the gaster and often obscured by the anterior edge of the gaster in the dorsal view. Gaster covered in dense pubescence; lacking sting; acidopore present at apex.

Male: ( no specimens in MEM; description based on pictures).
Color yellowish-tan with a brown gaster. Legs, especially joints, lighter colored than the body. Head weakly shining with pale, coarse, erect setae; sparse, short, hair-like setae present, especially anterior to eyes; eyes distinctly convex and about 1/3 the length of the head, situated at the midpoint of the head; three ocelli present; maxillary palps long and six-segmented; antennae 13-segmented with an elongate scape. Mesosoma mostly glabrous and shining with some coarse, erect setae; enlarged with four wings present. Waist single segmented; petiolar node triangular from lateral view. Gaster shining and glabrous with long, erect setae present; genitalia present at apex.

Biology and Economic Importance
Paratrechina longicornis is found in tropical and semi tropical habitats worldwide and is closely associated with human habitation. Its ability to inhabit disturbed environments and live along side humans is what has led to its widespread range. P. longicornis has also been able push its range into slightly less tropical environments by inhabiting heated buildings. When not nesting in houses, their nests can be found in mulch, rotten wood, tree cavities, or under other objects found on the ground. These ants are general scavengers and will readily be attracted to sugary foods and baits. P. longicornis can also be found tending honeydew producing Hemipterans. In the Southeastern United States P. longicornis has been collected from September to April and is one of the most commonly found ants in the winter months.

Paratrechina longicornis is considered to be a nuisance pest species due to its tendency to forage and nest in homes and buildings and the ease of which humans move it around. Colonies tend to be found in buildings, or nearby to building, more frequently than in natural undisturbed areas in the Southeastern United States. It is believed to have first entered the United States through Florida and has now spread across the Gulf Coast and Southern East Coast states. P. longicornis has a great sense of smell and will quickly find any food in the area and will readily feed on common household foods including meat, sweats, vegetables and fountain soda syrups.

Native Range: Asian origin argued by Wetterer (2008) and LaPolla et al. (2013). Looking at sister taxons suggests a possible African woodland origin (

Australian: Australia, Barrow Island, Cook Islands, Fiji, French Polynesia, Guam, Hawaii, Indonesia, Kiribati, Marshall Islands, Micronesia, New Caledonia, New Guinea, New Zealand, Niue, Norfolk Island, Northern Mariana Islands, Palau, Samoa, Solomon Islands, Timor-Leste, Tokelau, Tonga, Tuvalu, Vanuatu (
Ethiopian: Chad, Comoros, Democratic Republic of Congo, Eritrea, Europa Island, Guinea, Kenya, Madagascar, Malawi, Mali, Mauritania, Mauritius, Mayotte, Mozambique, Nigeria, Reunion, Saint Helena, Senegal, Seychelles, South Africa, Sudan, Tanzania, Uganda, United Arab Emirates, Yemen (
Nearctic: Baja California, United States ( and MEM).
Neotropical:  Anguilla, Aruba, Bahamas, Barbados, Belize, Bermuda, Brazil, British Virgin Islands, Cayman Islands, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, French Guiana, Galapagos Islands, Guatemala, Guyana, Haiti, Honduras, Jamaica, Martinique, Mexico, Nicaragua, Panama, Paraguay, Peru, Puerto Rico, Saint Kitts and Nevis, Saint Lucia, Trinidad and Tobago, Turks and Caicos Islands, Venezuela (
Oriental: Bangladesh, Borneo, Cambodia, Christmas Island, India, Krakatau Islands,
Malaysia, Nepal, Nicobar Island, Pakistan, Philippines, Singapore, Sri Lanka, Taiwan, Thailand, Vietnam (
Palearctic: Bahrain, Balearic Islands, Belgium, China, Estonia, France, Iran, Israel, Japan, Libya, Macaronesia, Malta, Saudi Arabia, Spain, United Kingdom of Great Britain and Northern Ireland (

U.S. Distribution: AL, AZ, CA, FL, GA, HI, LA, MS, NC, SC, TX ( and MEM).
Southeastern U.S. Distribution: AL, FL, GA, LA, MS, NC, SC ( and MEM).

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 (2001-2014) and USDA-ARS Areawide Management Invasive Ants 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
André, Ern. 1881. Catalogue raisonné des Formicides provenant du voyage en Orient de M. Abeille de Perrin et description des espèces nouvelles. Annales de la Société Entomologique de France (6)1:53-78.

Bolton, B. 2016.  Bolton World Catalog Ants. Available online: Accessed 9 March 2016.

Dalla Torre, K. W. 1893. Catalogus Hymenopterorum hucusque descriptorum systematicus et synonymicus. Vol. 7. Formicidae (Heterogyna).

Emery, C. 1892 ("1891"). Note sinonimiche sulle formiche. Bullettino della Società Entomologica Italiana 23:159-167.

Emery, C. 1910. Beiträge zur Monographie der Formiciden des paläarktischen Faunengebietes. (Hym.) Teil X. Deutsche Entomologische Zeitschrift 1910:127-132.

Forel, A. 1891. Les Formicides. [part]. In: Grandidier, A. 1891. Histoire physique, naturelle, et politique de Madagascar. Volume XX. Histoire naturelle des Hyménoptères. Deuxième partie (28e fascicule). Paris: Hachette et Cie, v + 237 pp.

Forel, A. 1894. Les Formicides de l'Empire des Indes et de Ceylan. Part IV. Journal of the Bombay Natural History Society 8:396-420.

Fox, E.G.P.; Solis, D.R.; Jesus, C.M.; Bueno, O.C.; Yabuki, A.T.; Rossi, M.L. 2007. On the immature stages of the crazy ant Paratrechina longicornis (Latreille 1802) (Hymenoptera: Formicidae). Zootaxa 1503: 1-11.

Hung, A. C. F.; Imai, H. T.; Kubota, M. 1972. The chromosomes of nine ant species (Hymenoptera: Formicidae) from Taiwan, Republic of China. Annals of the Entomological Society of America 65:1023-1025.

Jerdon, T. C. 1851. A catalogue of the species of ants found in Southern India. Madras Journal of Literature and Science 17:103-127.

LaPolla, J. S.; Brady, S. G.; Shattuck, S. O. 2010. Phylogeny and taxonomy of the Prenolepis genus-group of ants (Hymenoptera: Formicidae). Systematic Entomology 35:118-131.

LaPolla, J. S.; Hawkes, P. G.; Fisher, J. N. 2013. Taxonomic review of the ant genus Paratrechina, with a description of a new species from Africa. Journal of Hymenoptera Research 35:71-82.

Latreille, P. A. 1802. Histoire naturelle des fourmis, et recueil de mémoires et d'observations sur les abeilles, les araignées, les faucheurs, et autres insectes. Paris: Impr. Crapelet (chez T. Barrois), xvi + 445 pp.

Mayr, G. 1865. Formicidae. In: Novara Expedition 1865. Reise der Österreichischen Fregatte "Novara" um die Erde in den Jahren 1857, 1858, 1859. Zoologischer Theil. Bd. II. Abt. 1. Wien: K. Gerold's Sohn, 119 pp.

Roger, J. 1863. Verzeichniss der Formiciden-Gattungen und Arten. Berliner Entomologische Zeitschrift 7(Beilage):1-65.

Smith, M. R. 1965. House-infesting ants of the Eastern United States, their recognition, biology, and economic importance. United States Department of Agriculture, Technical Bulletin No. 1326: i-105.

Trager, J. C. 1984. A revision of the genus Paratrechina (Hymenoptera: Formicidae) of the continental United States. Sociobiology 9:49-162.
Wetterer, J.K. 2008. Worldwide spread of the longhorn crazy ant, Paratrechina longicornis (Hymenoptera: Formicidae). Myrmecoloigcal News 11, 137-149.

Wheeler, W. M. 1921. Chinese ants collected by Prof. C. W. Howard. Psyche (Cambridge) 28:110-115.

Wheeler, G. C.; Wheeler, J. 1986. Supplementary studies on ant larvae: Formicinae (Hymenoptera: Formicidae). Journal of the New York Entomological Society 94:331-341.