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Species Nylanderia fulva - Tawny Crazy Ant

Tawny Crazy Ant - Nylanderia fulva - female Tawny Crazy Ant - Nylanderia fulva - female Rasberry Crazy Ant - Nylanderia fulva long antennae ant - Nylanderia fulva - male lateral - Nylanderia fulva - male Nylanderia fulva queen - Nylanderia fulva - female Nylanderia fulva - male ant - Nylanderia fulva
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon (Aculeata - Ants, Bees and Stinging Wasps)
Superfamily Formicoidea (Ants)
Family Formicidae (Ants)
Subfamily Formicinae
Tribe Lasiini
Genus Nylanderia (Crazy Ants)
Species fulva (Tawny Crazy Ant)
Other Common Names
Tawny Crazy Ant (TCA) - is the official common name per ESA
Rasberry Crazy Ant (RCA) - (former) unofficial common name, at least in Texas. (Tom Rasberry first discovered the ant in the Houston area in 2002.)
The use of other common names such as Caribbean, hairy, brown, etc. should be discontinued for this sp...
Latin -- nee-lan-DEHR-ia (Anglicized -- nye-lan-DEER-ia)
Synonyms and other taxonomic changes
Current: Nylanderia fulva (Mayr). (Gotzek et al. 2012)
Orig. Comb: Prenolepis fulva Mayr 1862
Syn: Paratrechina fulva (Mayr)
Explanation of Names
fulva (L). 'tawny' (1)
Worker ants are all similar in size (they are monomorphic), with a body length of 1/8 inch.
Coloration: Adult colony members, including queens, males and workers, are reddish-brown (although lightness or darkness of their body color may vary)
Size: Worker ants are all similar in size (they are monomorphic), with a body length of 1/8 inch.
Worker ants have long legs and antennae, although not as long as the crazy ant, P. longicornis, and their bodies have numerous, long, coarse hairs. The antenna have 12-segments with no club.
There is a small circle of hairs (acidopore) present at tip of the abdomen (as opposed to the typical stinger found in most ants), a characteristic of formicine ants found within the Formicinae subfamily.
se US (Brownsville to Miami) - Range Map - Joe A. MacGown, 2015
The Tawny crazy ant was first found in Texas (near Pasadena, a southeast Houston suburb) in 2002.
Tawny crazy ant colonies can be found under or within almost any object or void, including stumps, soil, concrete, rocks, potted plants, etc.
Nests primarily occur outdoors, but worker ants will forage indoors, into homes and other structures.
Nesting occurs under almost any object that retains moisture.
These ants do not build centralized nests, beds, or mounds, and do not emerge to the surface from nests through central openings.
Few worker ants forage during cooler winter months.
In spring foraging activity begins and colonies grow, producing millions of workers that increase dramatically by mid-summer (July-August).
Ant numbers remain high through fall (October-November).
Tawny crazy ants eat almost anything; they are omnivorous.
Worker ants commonly "tend" sucking hemipterous insects such as aphids, scale insects, whiteflies, mealybugs, and others that excrete a sugary (carbohydrate) liquid called "honeydew" extracted from host plants when stimulated by the ants.
Workers are attracted to sweet parts of plants including nectaries, damaged and over-ripe fruit. See photo here:

Worker ants also consume other insects and other small vertebrates for protein.
Life Cycle
colonies contain numerous queens
Todd Staples, Texas Commissioner of Agriculture, suspects this to be a potentially serious agricultural pest. These ants show likelihood of being transported through movement of almost any infested container or material. Thus, movement of garbage, yard debris, bags or loads of compost, potted plants, bales of hay, can transport these ant colonies by truck, railroad, and airplane.
See Also
Nylanderia pubens (Caribbean Crazy Ant) - Featured Creatures - John Warner and Rudolph H. Scheffrahn, 2010 - University of Florida
Paratrechina longicornis may in some cases create massive, but localized numbers. These species look similar, but have marked differences. Paratrechina longicornis antennae, legs and thorax are all significantly longer than that of N. sp. nr. pubens. See photo:
- widely dist., non-native sp.
Although the use of color as an identification tool is not to be relied upon, the crazy ant is often jet black in color, especially when compared to the typically reddish-brown of N fulva.
Nylanderia fulva (Mayr) is a South American species and its relationship to N. pubens is uncertain. Nylanderia pubens was originally described as a subspecies of N. fulva, but was elevated to species rank by Trager (1984). Meyers (2008) addressed the question of whether the Texas populations referred to as N. nr. pubens were distinct from the Florida and Caribbean populations of N. pubens. Based on morphological and molecular data, he concluded that these are the same species. But, some questions linger, mainly with regard to relationships among N. pubens, N. fulva, and the various named subspecies of the latter. Until recently, no one had examined the type specimens, located in a museum in Geneva, Switzerland, to determine the morphological basis of the original names. Happily, the type comparisons and extensive systematic research necessary to unravel these problems are underway at John LaPolla’s lab at Towson State University. So, we should have the final answer to what the hairy crazy ant’s true identity is soon. - Carlton and Bayless (LSAM)
Also sometimes confused with cheese ants, Forelius sp.
Print References
LeBrun, E.G., J. Abbott, L.E. Gilbert. 2013. Imported crazy ant displaces imported fire ant, reduces and homogenizes grassland ant and arthropod assemblages. Biological Invasions (Abstract)
Gotzek, D., S.G. Brady, R.J. Kallal, J.S. LaPolla. 2012. The Importance of Using Multiple Approaches for Identifying Emerging Invasive Species: The Case of the Rasberry Crazy Ant in the United States. PLoS ONE 7(9): e45314. doi:10.1371/journal.pone.0045314 (Full Text)
LaPolla, J.S., S.G. Brady, S.O. Shattuck. 2010. Phylogeny and taxonomy of the Prenolepis genus-group of ants (Hymenoptera: Formicidae). Systematic entomology, 35: 118-131. (Abstract)
Meyers, Jason M. 2008. Identification, distribution and control of an invasive pest ant, Paratrechina sp. (Hymenoptera: Formicidae), in Texas. Unpublished Dissertation, Texas A&M University, College station. 177 pp. (Full PDF)
McDonald, D.L. 2012. Investigation of an invasive ant species: Nylanderia fulva colony extraction, management, diet preference, fecundity, and mechanical vector potential. Ph.D. Dissertation, Texas A&M University College Station, TX.
Trager, J.C. 1984. A revision of the genus Paratrechina (Hymenoptera: Formicidae) of the continental United States. Sociobiology 9: 51-162. (2)
Zenner-Polania, I. 1990. Biological aspects of the 'hormiga loca,' Paratrechina (Nylanderia) fulva (Mayr), in Colombia. Pp. 290-297 In: R.K. Vander Meer; K. Jaffe and A. Cedeno. (Editors) Applied myrmecology: a world perspective, Westview Press, Boulder, CO.
Internet References
Tawny crazy ant - Joe A. MacGown, 2013
Tawny (Rasberry) Crazy Ant, Nylanderia pubens - The Center for Urban and Structural Entomology at Texas A&M University
Featured Creatures - UFL info page
The Hairy Crazy Ant in Louisiana - Chris Carlton and Victoria Bayless, Louisiana State Arthropod Museum (LSAM)
'Crazy' ants wreaking havoc in Houston-area households By ALLAN TURNER, Houston Chronicle, May 14, 2008.
Tom Rasberry - Wikipedia, See Tom's blog here
Nylanderia fulva - Alex Wild Photography
Works Cited
1.Dictionary of Word Roots and Combining Forms
Donald J. Borror. 1960. Mayfield Publishing Company.
2.A revision of the genus Paratrechina (Hymenoptera: Formicidae) of the continental United States
Trager, J.C. 1984. 1984. Sociobiology.