Tetramorium caespitum

Geographic Range

Tetramorium caespitum are native to Europe and were introduced to North America in the 1700's. Pavement ants are now found in most of the eastern and southern United States. (Holldobler and Wilson, 1990; National Pest Management Association inc., 2001; Wheeler, 1910)

Habitat

Tetramorium caespitum tend to nest under sidewalks, stones, pavement, and in the crevices of housing structures (Day 1998).

Pavement ants prefer a temperature range of 10-40 degrees Celsius (Holldobler 1990). (Day, 1998; Holldobler and Wilson, 1990)

Physical Description

Tetramorium caespitum have dark brown bodies with pale legs. Both queen and male ants are larger than workers. Both queens and males have wings, which fall off shortly after mating. A typical worker (which is an unfertilized, sterile female) is about 3.25mm while the queen is about 8mm long. Pavement ants have 12-segmented antennae with a three -segmented club. On females, the thorax has a pair of small spines on the upper part while males do not have spines on their back. A stinger is present, and the pedicel has two segmented parts. Worker pavement ants have distinguishing characteristics. They have two clearly visible humps, and grooves or ridges running from anterior to the posterior part of their bodies (National Pest Management Assoc., 2001).

A colony can sustain about 10,000 workers who weigh about 6.5g in the aggregate (Wilson 1971). (National Pest Management Association inc., 2001; Wilson, 1971)

  • Range length
    2 to 4 mm
    0.08 to 0.16 in
  • Average length
    3.25 mm
    0.13 in

Development

Tetramorium caespitum hatch from the egg as grub-like larvae, and pass through three larval instars (growth stages) before they undergo complete metamorphosis into adult physiology. T. caespitum queens (there may be more than one) lay all of the eggs in the colony, which are cared for by workers throughout the development process. (Brian, 1965; Holldobler and Wilson, 1990; Werner and Olson, 1994)

Reproduction

Both queen and male ants have wings until shortly after mating. When environmental conditions are right, virgin queens and males fly into the air in order to copulate (called their nuptial flight). After mating takes place, they lose their wings and the young queens set out to start their nests while the males die. The queen stores all of the sperm from her nuptial flight in her spermatheca. There is enough sperm from that one flight that she can fertilize all of her eggs for the rest of her life. (Brian, 1965; Holldobler and Wilson, 1990; Werner and Olson, 1994)

Pavement ants have polygyne colonies (colonies that may have more than one queen). This means there colonies can grow very quickly and very large since there is more than one egg layer. Queens lay fertilized eggs that become workers or other queens, and unfertilized eggs that either develop into male ants or eaten by the colony. One queen will lay anywhere from five to forty eggs per day.

The queen stores all of the sperm from her nuptial flight in her spermatheca. There is enough sperm from that one flight that she can fertilize all of her eggs for the rest of her life. (Brian, 1965; Werner and Olson, 1994)

  • Breeding season
    June-July
  • Range gestation period
    28 to 30 days
  • Range age at sexual or reproductive maturity (female)
    30 to 45 days
  • Range age at sexual or reproductive maturity (male)
    30 to 45 days

Female workers care for all eggs, larvae, and pupae. The queen has no part in the care of her brood, her only job is to lay eggs.

Lifespan/Longevity

Individual workers live approximately 5 years, and queens may live much longer than that. Tetramorium caespitum are very adaptable to changes in their environment. (Holldobler and Wilson, 1990)

  • Average lifespan
    Status: wild
    5 years
  • Average lifespan
    Status: captivity
    5 years

Behavior

Tetramorium caespitum is known for its aggressive behavior toward nest intruders, as well as other ant species. T. caespitum can often be found battling other ant individuals or even entire colonies, and will fight until either death or injury occurs. (Holldobler and Wilson, 1990)

Communication and Perception

Pavement ants use chemical signals in order to communicate with one another. When foraging for food, Tetramorium caespitum workers will leave a chemical trail by wiping their gasters on the ground as they walk. In this way, workers may follow trails to food, and also find their way back to the nest without getting lost. T. caespitum have been observed to not travel more than 30 meters from their nest, and therefore generally stay closer to home than many ant species. In addition to chemical signals (called pheromones), pavement ants use polarized light to navigate and guide their paths. (Holldobler and Wilson, 1990)

Food Habits

Tetramorm caespitum are scavengers and will eat almost anything left within their territory. T. caespitum tend to be drawn toward sugary food. The pavement ant also stores seeds and grains in its nest for later use. T. caespitum has a mutualistic relationship with several species of lycaenid caterpillar. Pavement ants drink nectar produced by the caterpillars, and in return ants provide shelter and protect the caterpillers from predators. (Holldobler and Wilson, 1994; Wheeler, 1910)

  • Animal Foods
  • body fluids
  • carrion
  • insects
  • terrestrial non-insect arthropods
  • Plant Foods
  • seeds, grains, and nuts
  • fruit
  • nectar
  • pollen
  • flowers
  • sap or other plant fluids

Predation

T. caespitum has a foul taste when eaten due to a toxin produced by the species. Pavement ants also possess a stinger, and give off a smell of banana oil that aids in deterring potential predators. (Werner and Olson, 1994)

  • Known Predators
    • none known

Ecosystem Roles

Tetramorium caespitum is the host for many parasitic ant species. The most common is Teleutomyrmex schneideri. The T. schneideri queen lives with the T. caespitum queen, often sitting on the pavement ant queen's back in order remain within the nest. Other parasitic ants include Anergates atratlus and species of Strongylognathus.

Pavement ants may host the caterpillars of lycaenid butterflies, including Lycaeides melissa. The caterpillars secret sugary compounds that the ants consume, and the ants allow the caterpillars to spend the winter in their nest.

These ants also aerate soil as they dig their nests. (Wilson, 1971)

Mutualist Species
Commensal/Parasitic Species

Economic Importance for Humans: Positive

Pavement ants provide no direct economic benefit to humans.

Economic Importance for Humans: Negative

Pavement ants excavate large amounts of sand and soil from under roads, walkways and shallow building foundations. Over time this activity can cause these items to sink and settle causing structural damage. The most common complaint about pavement ants however, is of ants foraging for food in peoples houses. These ants can also sting. (Holldobler and Wilson, 1990)

  • Negative Impacts
  • injures humans
    • bites or stings
  • household pest

Conservation Status

There is no threat to this species.

Other Comments

Tetramorium caespitum workers are an intermediate host of the poultry tapeworms Raillietina tetragona and Raillietina chinobothrida. (National Pest Management Association inc., 2001)

Contributors

Sara Diamond (editor), Animal Diversity Web.

Nancy Shefferly (editor), Animal Diversity Web.

Lynn Tarkington (author), Southwestern University, Stephanie Fabritius (editor), Southwestern University.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carrion

flesh of dead animals.

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

coprophage

an animal that mainly eats the dung of other animals

delayed fertilization

a substantial delay (longer than the minimum time required for sperm to travel to the egg) takes place between copulation and fertilization, used to describe female sperm storage.

diurnal
  1. active during the day, 2. lasting for one day.
ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

eusocial

the condition in which individuals in a group display each of the following three traits: cooperative care of young; some individuals in the group give up reproduction and specialize in care of young; overlap of at least two generations of life stages capable of contributing to colony labor

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

internal fertilization

fertilization takes place within the female's body

introduced

referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

metamorphosis

A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.

migratory

makes seasonal movements between breeding and wintering grounds

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

omnivore

an animal that mainly eats all kinds of things, including plants and animals

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polarized light

light waves that are oriented in particular direction. For example, light reflected off of water has waves vibrating horizontally. Some animals, such as bees, can detect which way light is polarized and use that information. People cannot, unless they use special equipment.

polyandrous

Referring to a mating system in which a female mates with several males during one breeding season (compare polygynous).

polymorphic

"many forms." A species is polymorphic if its individuals can be divided into two or more easily recognized groups, based on structure, color, or other similar characteristics. The term only applies when the distinct groups can be found in the same area; graded or clinal variation throughout the range of a species (e.g. a north-to-south decrease in size) is not polymorphism. Polymorphic characteristics may be inherited because the differences have a genetic basis, or they may be the result of environmental influences. We do not consider sexual differences (i.e. sexual dimorphism), seasonal changes (e.g. change in fur color), or age-related changes to be polymorphic. Polymorphism in a local population can be an adaptation to prevent density-dependent predation, where predators preferentially prey on the most common morph.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

soil aeration

digs and breaks up soil so air and water can get in

sperm-storing

mature spermatozoa are stored by females following copulation. Male sperm storage also occurs, as sperm are retained in the male epididymes (in mammals) for a period that can, in some cases, extend over several weeks or more, but here we use the term to refer only to sperm storage by females.

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

urban

living in cities and large towns, landscapes dominated by human structures and activity.

venomous

an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

References

Brian, M. 1965. Social Insect Populations. Great Britain: W & J Mackay & Co..

Day, E. 1998. "Pavement Ant" (On-line). Accessed 23 Nov 2001 at http://www.ext.vt.edu/departments/entomology/factsheets/pavement.html.

Holldobler, B., E. Wilson. 1994. Journey to the Ants. Cambridge, Massachusetts: Belknap Press of Harvard University Press.

Holldobler, B., E. Wilson. 1990. The Ants. Cambridge, Massachusetts: Belknap Press.

Lothan Wildlife, 2002. "Pavement Ant" (On-line). Accessed 23 Nov 2001 at http://download.edinburgh.gov.uk/biodiversity/080%20An%20Ant.pdf.

National Pest Management Association inc., 2001. "Welcome to the Pest World" (On-line). Accessed 23 Nov 2001 at http://www.pestworld.com/homeowners/spotlight/pavement_ant.asp.

Werner, F., C. Olson. 1994. Insects of the Southwest. Tuscon, AZ: Fisher Books.

Wheeler, W. 1910. Ants: Their Structure, Development and Behavior. New York: Columbia University Press.

Wilson, E. 1971. The Insect Societies. Cambridge, Mass: Belknap Press.