The book of earth

"Red ant" redirects here. For the species Pogonomyrmex barbatus, see Red harvester ant.
Fire ant is the common name for several species of ants in the genus Solenopsis. They are, however, only a minority in the genus, which includes over 200 species of Solenopsis worldwide. Solenopsis are stinging ants and most of their common names reflect this, for example, ginger ants and tropical fire ants. Many species also are called red ants because of their light brown color, though species of ants in many other genera are similarly named for similar reasons. Examples include Myrmica rubra and Pogonomyrmex barbatus.

None of these names applies in all countries nor to all species of Solenopsis, nor only to Solenopsis species; for example the colloquial names for several species of weaver ants in the genus Oecophylla in Southeast Asia include "fire ants" because of their red color and painful sting; the two genera, however, are not closely related. Also, Wasmannia auropunctata is commonly called the "little fire ant".

Appearance


Fire ant mound

Detail of the head (Solenopsis geminata)
The bodies of mature fire ants, like the bodies of all typical mature insects, are divided into three sections: the head, the thorax, and the abdomen, with three pairs of legs and a pair of antennae. Fire ants of those species invasive in the United States can be distinguished from other ants locally present, by their copper brown head and body with a darker abdomen. The worker ants are blackish to reddish, and their size varies from 2 to 6 mm (0.079 to 0.236 in). In an established nest these different sizes of ants all are present at the same time.

Solenopsis spp. ants can be identified by three body features—a pedicel with two nodes, an unarmed propodeum, and antennae with 10 segments plus a two-segmented club. Many ants bite, and formicine ants can cause irritation by spraying formic acid; myrmecine ants like fire ants have a dedicated venom-injecting sting, which injects an alkaloid venom, as well as mandibles for biting.

Behavior


A fire ant worker, queen, and male (clockwise from bottom left)
A typical fire ant colony produces large mounds in open areas, and feeds mostly on young plants and seeds. Fire ants often attack small animals and can kill them. Unlike many other ants, which bite and then spray acid on the wound, fire ants bite only to get a grip and then sting (from the abdomen) and inject a toxic alkaloid venom called Solenopsin, a compound from the class of piperidines. For humans, this is a painful sting, a sensation similar to what one feels when burned by fire (hence the name) and the after effects of the sting can be deadly to sensitive people. Fire ants are more aggressive than most native species and so have pushed many species away from their local habitat. One such species that Solenopsis ants parasitically take advantage of are bees, such as Euglossa imperialis, a non-social orchid bee species, from which the ants would enter the cells from below the nest and rob the cell's contents. These ants are renowned for their ability to survive extreme conditions. They do not hibernate, but can survive cold conditions, although this is costly to fire ant populations as observed during several winters in Tennessee, where 80 to 90% of colonies died due to several consecutive days of extremely low temperatures.

Fire ants nest in the soil, often near moist areas, such as river banks, pond shores, watered lawns, and highway shoulders. Usually, the nest will not be visible, as it will be built under objects such as timber, logs, rocks, or bricks. If there is no cover for nesting, dome-shaped mounds will be constructed, but these are usually only found in open spaces, such as fields, parks and lawns. These mounds can reach heights of 40 cm (16 in), but can be even higher on heavier soils, standing at 1.0m in height and 1.5m in diameter. Colonies are founded by small groups of queens or single queens. Even if only one queen survives, within a month or so, the colony can expand to thousands of individuals. Some colonies may be polygynous (having multiple queens per nest).

Roles



Solenopsis winged reproductive females, queens and workers
Fire ant queens, the reproductive females in their colony, also are generally the largest. Their primary function is reproduction; fire ant queens may live up to 7 years and can produce up to 1,600 eggs per day, and colonies will have as many as 250,000 workers. The estimated potential life span is around 5.83 to 6.77 years. Young, virgin fire ant queens have wings (as do male fire ants), but they rip them off after mating.

Males mate with the queen. They die immediately after mating.

There are other types of roles in an ant colony like the workers and the soldier ants. The soldier ants are known for their larger and more powerful mandibles while the worker takes care of regular tasks (the main tasks in a colony are caring for the eggs/larvae/pupae, cleaning the nest, and foraging for food). However, Solenopsis daguerrei colonies contain no workers, as they are considered social parasites.

Invasive species

For more details on invasive species, see Red imported fire ant.

Sign for the Fire Ant Festival in Ashburn, Georgia
Although most fire ant species do not bother people and are not invasive, Solenopsis invicta, known in the United States as the red imported fire ant (or RIFA) is an invasive pest in many areas of the world, notably the United States, Australia, China and Taiwan. The RIFA was believed to have been accidentally introduced to these countries via shipping crates, particularly with Australia when they were first found in Brisbane in 2001. These ants have now since been spotted in Sydney for the first time. They were believed to be in the Philippines, but they are most likely to be misidentified for Solenopsis geminata ants.

In the US the FDA estimates that more than US$5 billion is spent annually on medical treatment, damage, and control in RIFA-infested areas. Furthermore, the ants cause approximately $750 million in damage annually to agricultural assets, including veterinarian bills and livestock loss, as well as crop loss. Over 40 million people live in RIFA-infested areas in the southeastern United States. about 60% of people living in fire ant-infested areas are stung each year. RIFA are currently found in humid southeastern USA states including parts of Texas, Louisiana, Mississippi, Alabama, Georgia and Florida.

Since September 2004 Taiwan has been seriously affected by the red fire ant. The US, Taiwan and Australia all have ongoing national programs to control or eradicate the species, but, except for Australia, none have been especially effective. In Australia, there is an intensive program costing A$175 million, although the fire ant had remained despite efforts. By July 2013 multiple sites west of Brisbane were confirmed, including the Lockyer Valley, Muirlea and Goodna. According to a study published in 2009, it only took seventy years for the lizards in parts of the United States to adapt to the ant's presence – they now have longer legs and new behaviors that aid them in escaping from the danger.

Symptoms and treatment


A human leg three days after brief contact with a fire ant colony
The venom of fire ants is composed of alkaloids derived from piperidine (see Solenopsis saevissima). Some people are allergic to the venom, and as with many allergies, may experience anaphylaxis, which requires emergency treatment. Management of an emergency visit due to anaphylaxis is recommended with the use of adrenaline. The sting swells into a bump, which can cause much pain and irritation, especially when several stings are in the same place. The bump often forms into a white pustule, which can become infected if scratched, but if left alone will usually flatten within a few days. The pustules are obtrusive and uncomfortable while active and, if they become infected, can cause scarring.

First aid for fire ant stings includes external treatments and oral medicines. There are also many home remedies of varying efficacy, including immediate application of urine or aloe vera gel, the latter of which is also often included in over-the-counter creams that also include medically tested and verified treatments. External, topical treatments include the anesthetic benzocaine, the antihistamine diphenhydramine, and the corticosteroid hydrocortisone. Antihistamines or topical corticosteroids may help reduce the itching and will generally benefit local sting reactions. Oral medicine include antihistamines. Severe allergic reactions to fire ant stings, including severe chest pain, nausea, severe sweating, loss of breath, serious swelling, and slurred speech, can be fatal if not treated.

Predators


Dionaea muscipula trap

A species of Drosera with its sticky leaves that trap many ants

Pseudacteon curvatus, phorid fly parasitoid of fire ants
Phorid flies, or Phoridae, are a large family of small, hump-backed flies somewhat smaller than vinegar flies; two species in this family (Pseudacteon tricuspis and Pseudacteon curvatus) are parasitoids of the red imported fire ant in its native range in South America. Some 110 species of the genus Pseudacteon, or ant-decapitating flies, have been described. Members of Pseudacteon reproduce by laying eggs in the thorax of the ant. The first instar larvae migrates to the head, then develops by feeding on the hemolymph, muscle tissue, and nervous tissue. After about two weeks, they cause the ant's head to fall off by releasing an enzyme that dissolves the membrane attaching the ant's head to its body. The fly pupates in the detached head capsule, emerging two weeks later.

Pseudacteon flies appear to be important ecological constraints on Solenopsis species and they have been introduced throughout the southern United States, starting with Travis, Brazos, and Dallas counties in Texas, as well as south central Alabama, where the ants first entered North America.

The Venus flytrap, a carnivorous plant, is native to North and South Carolina in the United States. About 33% of the prey of the Venus flytrap are ants of various species. They lure their prey with a sweet sap. Once the prey has entered the trap and within about 3 seconds has touched two or three "trigger hairs", bristles on the surface of the trap, the leaf closes around the prey, confining it behind the "teeth" on its perimeter, and digests it. The majority of ants that were captured included non-native RIFAs, and three other species of ants. Other carnivorous plants, such as sundews (Drosera) and various kinds of pitcher plants also trap many ants.

Species

Main article: List of Solenopsis species
The genus contains over 200 species. They include:

Solenopsis daguerrei (Santschi, 1930)
Solenopsis fugax (Latreille, 1798)
Solenopsis invicta Buren, 1972
Solenopsis molesta (Say, 1836)
Solenopsis richteri Forel, 1909
Solenopsis saevissima (Smith, 1855)
Solenopsis silvestrii Emery, 1906
Solenopsis solenopsidis (Kusnezov, 1953)
Solenopsis xyloni McCook, 1879

source - Wikipedia

This article is about the ant Myrmecia pilosula. For other jack jumper ants, see Jack jumper ant (disambiguation). For Jerdon's jumping ant, see Harpegnathos saltator.
The jack jumper ant (Myrmecia pilosula), commonly known as the hopper ant, jumper ant or jumping jack, is a species of venomous ant native to Australia. Most commonly found in Tasmania and southeast Australia, it is a member of the genus Myrmecia, subfamily Myrmeciinae, and was formally described and named by British entomologist Frederick Smith in 1858. This species is known for the ability to jump long distances. These ants are large; workers and males are approximately the same size: 12 to 14 millimetres (0.47 to 0.55 in) for workers, and 11 to 12 millimetres (0.43 to 0.47 in) for males. The queen measures approximately 14 to 16 millimetres (0.55 to 0.63 in) in length and is similar in appearance to workers, whereas males are identifiable by their perceptibly smaller mandibles.

Jack jumper ants are primarily active during the day and live in open habitats, nesting in bushland, woodland and dry open forests, surrounded by gravel and sandy soil, which can be found in rural areas and are less common in urban areas. They prey on small insects and use their barbless stinger to kill other insects by injecting venom. Other ants and predatory invertebrates prey on the jack jumper. The average worker has a life expectancy of over one year. Workers are gamergates, allowing them to reproduce with drones, whether or not a queen is present in the colony. The ant is a part of the Myrmecia pilosula species complex; this ant and other members of the complex are known to have a single pair of chromosomes.

Their sting generally only causes a mild local reaction in humans; however, it is one of the few ant species that can be dangerous to humans, along with other ants in the genus Myrmecia. The ant venom is particularly immunogenic for an insect venom; the venom causes about 90% of Australian ant allergies. In endemic areas, up to 3% of the human population has developed an allergy to the venom and about half of these allergic people can suffer from anaphylactic reactions (increased heart rate, falling blood pressure, and other symptoms), which can lead to death on rare occasions. Between 1980 and 2000, there were four deaths due to anaphylaxis from jack jumper stings, all of them in Tasmania. Individuals prone to severe allergic reactions caused by the ant's sting can be treated with allergen immunotherapy (desensitisation).

Taxonomy and common names

Original holotype specimen (abdomen missing) Ponera ruginoda
The specific name derives from the Latin word pilose, meaning 'covered with soft hair'. The ant was first identified in 1858 by British entomologist Frederick Smith in his Catalogue of hymenopterous insects in the collection of the British Museum part VI, under the binomial name Myrmecia pilosula from specimens he collected in Hobart in Tasmania. There, Smith described the specimens of a worker, queen and male. The type specimen is located in the British Museum in London. In 1922, American entomologist William Morton Wheeler established the subgenus Halmamyrmecia characterised by its jumping behaviour, of which the jack jumper ant was designated as the type species. However, John Clark later synonymised Halmamyrmecia under the subgenus Promyrmecia in 1927 and placed the ant in the subgenus in 1943. William Brown synonymised Promyrmecia due to the lack of morphological evidence that would make it distinct from Myrmecia and later placed the jack jumper ant in the genus in 1953.

One synonym for the species has been published – Ponera ruginoda (also titled Myrmecia ruginoda), described by Smith in the same work, and a male holotype specimen was originally described for this synonym. Ponera ruginoda was initially placed into the genera Ectatomma and Rhytidoponera, but it was later classified as a junior synonym of the jack jumper ant, after specimens of each were compared. The ant is a part of the Myrmecia pilosula species complex, a species group that was first defined by Italian entomologist Carlo Emery. The species complex is a monophyletic group, where the species are closely related to each other but their actual genetic relationship is distant. Members of this group include M. apicalis, M. chasei, M. chrysogaster, M. croslandi, M. cydista, M. dispar, M. elegans, M. harderi, M. ludlowi, M. michaelseni, M. occidentalis M. queenslandica, M. rugosa and M. varians. Additional species that were described in this group in 2015 include M. banksi, M. haskinsorum, M. imaii and M. impaternata.

Their characteristic jumping motion when agitated or foraging inspires the common name "jack jumper", a behaviour also shared with other Myrmecia ants, such as Myrmecia nigrocincta. This is the most common name for the ant, along with "black jumper," "hopper ant", "jumper ant", "jumping ant", "jumping jack" and "skipper ant". It is also named after the jumping-jack firecracker. The species is a member of the genus Myrmecia, a part of the subfamily Myrmeciinae.

Description

Closeup view of a specimen. These ants attack with both its mandibles and sting.
Like its relatives, the ant possesses a powerful sting and large mandibles. These ants can be black or blackish-red in colour, and may have yellow or orange legs. The ant is medium-sized in comparison to other Myrmecia species, where workers are typically 12 to 14 millimetres (0.47 to 0.55 in) long. Excluding mandibles, jack jumpers measure 10 millimetres (0.39 in) in length. The ant's antennae, tibiae, tarsi and mandibles are also yellow or orange. Pubescence (hair) on the ant is greyish, short and erect, and is longer and more abundant on their gaster, absent on their antennae, and short and suberect on their legs. The pubescence on the male is grey and long, and abundant throughout the ant's body, but it shortens on the legs. The mandibles are long and slender (measuring 4.2 millimetres (0.17 in)), and concaves around the outer border.

The queen has a similar appearance to the workers, but its middle body is more irregular and coarser. The queen is also the largest, measuring 14 to 16 millimetres (0.55 to 0.63 in) in length. Males are either smaller or around the same size as workers, measuring 11 to 12 millimetres (0.43 to 0.47 in). Males also have much smaller triangular mandibles than workers and queens. The mandibles on the male contain a large tooth at the centre, among the apex and the base of the inner border. Punctures (tiny dots) are noticeable on the head, which are large and shallow, and the thorax and node are also irregularly punctuated. The pubescence on the male's gaster is white and yellowish.

Distribution and habitat

Two workers stand guard in front of the entrance to their nest
Further information: Ant colony
Jack jumper ants are abundant in most of Australia, being among the most common bull ant to be encountered. The ants can be found in the south-western tip of Western Australia, where it has been seen in the sand hills around Albany, Mundaring, Denmark and Esperance. The ant is rarely sighted in the northern regions of Western Australia. In South Australia, it is commonly found in the south-east regions of the state, frequently encountered in Mount Lofty (particularly the Adelaide Hills), Normanville, Hallett Cove and Aldgate, but it is not found in north-western regions. There are dense populations on the western seaboard of Kangaroo Island. Jack jumpers are widespread throughout the whole of Victoria, but the species is uncommon in Melbourne. However, populations have been collected from the suburb of Elsternwick, and they are commonly found in the Great Otway Ranges, with many nests observed around Gellibrand. In New South Wales, nests are found throughout the entire state (with the exception of north-western New South Wales), but dense populations are mostly found in the Snowy Mountains, Blue Mountains and coastal regions. The ants are widespread in the Australian Capital Territory. In Queensland, the ants are only found along the south-eastern coastlines of the state, where populations are frequently encountered in the Bunya Mountains, Fletcher, Stanthorpe, Sunshine Coast, Tamborine Mountain and Millmerran, and have been found as far north as Rockhampton.[a] The ant also resides in all of Tasmania, and their presence in the Northern Territory has not been verified.

Jack jumper ants live in open habitats, such as damp areas, forests, pastures, gardens and lawns, preferring fine gravel and sandy soil. Colonies can also be spotted around light bushland. Their preferred natural habitats include woodlands, dry open forests, grasslands and rural areas, and less common in urban areas. Their nests are mounds built from finely granular gravel, soil and pebbles, measuring 20 to 60 centimetres (8 to 24 in) in diameter and can be as tall as half of a metre (20 in) in height. Two types of nests for this species have been described: one being a simple nest with a noticeable shaft inside, the other being a complex structure surrounded by a mound. These ants utilise the warmth by decorating their nests with dry materials that heat in a quick duration, providing the nest with solar energy traps. They decorate their nests with seeds, soil, charcoal, stones, sticks, and even small invertebrate corpses. They also camouflage their nests by covering leaf litter, debris and long grass over the nest. Nests can be found hidden under rocks, where queens will most likely form their colony, or around small piles of gravel instead. Their range in southern Australia, like other regional ant species, appears like that of a relict ant. Jack jumpers have been found in dry sclerophyll forests, at elevations ranging from 121 to 1,432 metres (397 to 4,698 ft), averaging 1,001 metres (3,284 ft). Rove beetles in the genus Heterothops generally thrive in jack jumper nests and raise their brood within their chambers, and skinks have been found in some nests.

Worker dragging a pebble

Populations are dense in the higher mountain regions of Tasmania. Widespread throughout the state, their presence is known on King Island, located north-west from Tasmania. The ant prefers rural areas, found in warm, dry, open eucalypt woodlands; the climate provides the ant with isolation and warmth. This environment also produces the ant's food, which includes nectar and invertebrate prey. In suburban areas, this ant is found in native vegetation, and use rockeries, cracks in concrete walls, dry dirt and grass to build nests. One study found suburbs with voluminous vegetation cover such as Mount Nelson, Fern Tree and West Hobart host jack jumper populations, while the heavily urbanised suburbs of North Hobart and Battery Point, do not.

Pest control of the jack jumper ant is successful in maintaining their populations around suburban habitats. Chemicals like bendiocarb, chlorpyrifos, diazinon and permethrin are effective against them. Spraying of Solfac into nests is an effective way of controlling nests if they are in a close range of areas with considerable amounts of congestion and human activity. Pouring carbon disulfide into nest holes and covering entrances up with soil is another method of removing colonies. The Australian National Botanic Gardens has an effective strategy of marking and maintaining jack jumper nests.

Behaviour and ecology

Worker foraging on top of a dry flower
Primarily diurnal, workers search for food during the day until dusk. They are active during warmer months, but are dormant during winter. Fights between these ants within the same colony is not uncommon. They are known for their aggression towards humans, attraction to movement and well developed vision, being able to observe and follow intruders from a metre (1.1 yd) away. This species is an accomplished jumper ants with leaps ranging from 2 to 3 inches (51 to 76 mm). William Morton Wheeler compared jack jumper ants to "Lilliputian cavalry galloping to battle" when disturbed, due to their jumping behaviour. He further wrote that they also made a ludicrous appearance as they emerge from their nests, in a series of short hops.

While no studies have established whether or not these ants contain alarm pheromones, its relative Myrmecia gulosa is capable of inducing territorial alarm using pheromones. If proven, this would explain their ability to attack en masse. Foraging workers are regularly observed on the inflorescences of Prasophyllum alpinum (mostly pollinated by wasps of the subfamily Ichneumonidae). Although pollinia are often seen in the ants' jaw, they have a habit of cleaning their mandibles on the leaves and stems of nectar-rich plants before moving on, preventing pollen exchange. It is unknown whether jack jumper ants contribute to pollination.

Worker foraging on a branch

Unlike many other ants that use scent to forage for food, jack jumpers use their sight to target their prey. Like other bull ants, they are solitary when they forage, but only workers perform this role. These ants are omnivores and scavengers, typically foraging in warmer temperatures. They deliver painful stings, which are effective in both killing prey and deterring predators. Jack jumpers have smooth stingers, and can thus sting indefinitely. Jack jumper ants are skilled hunters, partially due to their excellent vision; they can even kill and devour wasps and bees. They also kill and eat other ants, such as carpenter ants (Camponotus) and feed on sweet floral secretions and other sugar solutions. Jack jumpers often hunt for spiders, and will sometimes follow their prey for a short distance, usually with small insects and small arthropods. Jack jumper ants, alongside M. simillima, have been given frozen houseflies (Musca domestica) and blowflies (Calliphoridae) as food under testing conditions. The ant has been observed to run and leap energetically at flies when they land, particularly on Acacia shrubs, plants or trees. Jack jumpers and other Myrmecia ants prey on insects such as cockroaches and crickets.

Mature adult ants of this species mostly eat sweet substances, so dead insects are given to their larvae collected while foraging. However, larvae are only fed insects when they have reached a particular size. Workers will mostly collect small insects, sap-sucking insects along with the honeydew which is taken to their nest to feed their young. Observations have been made of fly predation by jack jumper ants; they would only attack the smaller fly species and ignore larger flies.

Blindsnakes of the family Typhlopidae are known to consume Myrmecia broods, although smaller blindsnakes avoid them since they are vulnerable to their stings. Predatory invertebrates such as assassin bugs and redback spiders prey on jack jumpers and other Myrmecia ants, and echidnas, particularly the short-beaked echidna (Tachyglossus aculeatus) hunt jack jumper ants, eating their larvae and eggs. Nymphs of the assassin bug species Ptilocnemus lemur lure these ants by trying to make the ant sting them. The jack jumper ant is a host to the parasite gregarines (Gregarinasina). Ants that host this parasite change colour from their typical black appearance to brown. This was discovered when brown jack jumpers were dissected and found to have gregarinasina spores, while black jack jumpers showed no spores. If it is present in large numbers, the parasite interferes with the normal darkening of the cuticles while the ant is in its pupal stage. The cuticle softens due to the gregarine parasite.

Like every ant, the life of a jack jumper ant starts from an egg. If the egg is fertilised, the ant will be a female (diploid); if not, it will become a male (haploid). They develop through complete metamorphosis, meaning that they pass through a larva and pupa stage before emerging as an adult. Cocoons that are isolated from the colony are able to shed their pupal skin before hatching, allowing themselves to advance to full pigmentation. Newborns can also eclose (emerge from their pupa stage) without assistance from other ants. Once born, jack jumper ants can identify distinct tasks, an obvious primitive trait Myrmecia ants are known for.

Based on observations of six worker ants, the average life expectancy of the jack jumper is around 1.3 years, but workers were shown to live as little as 1.12 years or as long as 1.6, with the queen living much longer than the workers at 10 years or more. This datum gives a life expectancy of 401–584 days, with an average of 474 days. Egg clumping is common, as observed in laboratory colonies. These clumps are often carried by worker ants, and these clumps would contain two to 30 eggs, without any larvae to hold them together. This confirms that eggs from jack jumper colonies do not always lie singly apart. George C. Wheeler and Jeanette Wheeler (1971) studied and described larvae collected from New South Wales and South Australia. They noted that very young larvae of the jack jumper were 2.4 millimetres (0.094 in) in length, with two types of body hair. They also described young larvae (matured from very young larvae) at 2.7 mm (0.11 in), but with similar body characteristics to mature larvae, at 12.5 mm (0.49 in).

Drones (males) emerging from their nest

Queens are polyandrous, meaning that queens will mate more than once; queens mate with one to nine males during a nuptial flight, and the effective number of mates per queen ranges from 1.0 to 11.4. Studies show that most queen ants will only mate with one or two males. If the number of available male mates increases, the number of effective matings per queen decreases. Colonies are polygynous, meaning that a colony may house multiple queens; there are on average one to four queens per colony, and in multiple-queen colonies, the egg-laying queens are unrelated to one another. Based on a study, 11 of the 14 colonies tested were polygynous (78.57%), showing that this is common in jack jumper colonies. When the queen establishes a nest after mating, she will hunt for food to feed her young, making her semi-claustral. Nests can hold as few as 500 ants or as many as 800 to 1,000. Excavated nests typically have populations ranging from 34 to 344 individuals. Jack jumper ant workers are gamergates, having the ability to reproduce in colonies with or without queens.

Colonies are mainly polygynous with polyandrous queens, however, polyandry in jack jumper colonies is low in comparison to other Myrmecia ants, but it is comparable to M. pyriformis ants. In 1979, Craig and Crozier investigated the genetic structure of jack jumper ant colonies, and although queens are unrelated to each other as mentioned previously, the occurrence of related queens in a single colony was possible. During colony foundation, there are suggestions of dependent colony foundation in jack jumper queens, although independent colony foundations can occur, as the queens do have fully developed wings and can fly. Isolation by distance (IBD) patterns have been recorded, specifically where nests that tend to be closer to each other were more genetically similar in comparison to other nests farther away.

As colonies closer to each other are more genetically similar, independent colony foundation is most likely associated with nuptial flight if they disperse far from genetically similar colonies they originate from. Inseminated queens could even seek adoption into alien colonies if a suitable nest site area for independent colony foundation is restricted or cannot be carried out, known as the nest-site limitation hypothesis. Some queens could even try to return to their nests that they came from after nuptial flight, but end in another nest, in association that nests nearby will be similar to the queens birth nest.

Genetics

The jack jumper ant genome is contained on a single pair of chromosomes (males have just one chromosome, as they are haploid). This is the lowest number known (indeed possible) for any animal, a number shared with the parasitic roundworm Parascaris equorum univalens. Jack jumper ants are taxonomically discussed as a single biological species in the Myrmecia pilosula species complex. The ant has nine polymorphic loci, which yielded 67 alleles.

Interaction with humans

The earliest known account of ant sting fatalities in Australia was first recorded in 1931; two adults and an infant girl from New South Wales died from ant stings, possibly from the jack jumper ant or Myrmecia pyriformis. 30 years later, another fatality was reported in 1963 in Tasmania. Historical and IgE results have suggested these two species or perhaps another species were responsible for all recorded deaths.

Between 1980 and 2000, there have been four recorded deaths, all in Tasmania and all due to anaphylactic shock.[a] All known patients who died from jack jumper stings were at least 40 years old and had cardiopulmonary comorbidities. Severe laryngeal oedema and coronary atherosclerosis was detected in most of the autopsies of those who died. Most of the victims died within 20 minutes after being stung. Prior to any desensitisation program being established, the fatality rate was one person every four years from the sting.

Before venom immunotherapy, whole body extract immunotherapy was widely used due to its apparent effectiveness, and it was the only immunotherapy used on ants. However, fatal failures were reported and this led to scientists researching for alternative methods of desensitisation. Whole body extract immunotherapy was later proven to be ineffective, and venom immunotherapy was found to be safe and effective to use. Paul Clarke first drew medical attention to the jack jumper ant in 1986, and before this, there had been no history of records of allergic reactions or study on their sting venom. The identification of venom allergens began in the early 1990s in preparation for therapeutic use. Whole body extracts were first used to desensitize patients, but it was found to be ineffective and later withdrawn. Venom immunotherapy was shown to reduce the risk of systemic reactions, demonstrating that immunotherapy can be provided for ant-sting allergies.

In 2003, Professor Simon Brown established the jack jumper desensitisation program, although the program is at risk of closure. Since the establishment of the program, no death has been recorded since 2003. However, the ant may be responsible for the death of a Bunbury man in 2011.

The extent of the jack jumper sting problem differs among areas. Allergy prevalence rates are significantly lower in highly urbanised areas and much higher in rural areas. These ants represent a hazard towards people in the southern states of Australia, due to a high proportion of the population having significant allergies to the ant's sting. The ant is a significant cause of major insect allergies, responsible for most anaphylaxis cases in Australia, and rates of anaphylaxis are twice those of honeybee stings. One in three million annually die of general anaphalaxis in Australia alone. Over 90% of Australian ant venom allergies have been caused by the jack jumper.

The ant is notorious in Tasmania, where most fatalities have been recorded. In 2005, over a quarter of all jack jumper sting incidents were sustained in Tasmania; excessive in comparison to its 2006 population of only 476,000 people. Jack jumper stings are the single most common cause of anaphylaxis in patients at the Royal Hobart Hospital. The ant has also been a major cause of anaphylaxis outside Tasmania, notably around Adelaide and the outskirts of Melbourne, while cases in New South Wales and Western Australia have been more distributed. One in 50 adults have been reported to suffer anaphylaxis due to the jack jumper or other Myrmecia ants.

 Ant venom

The jack jumper ant and its relatives in the genus Myrmecia are among the most dangerous ant genera and have fearsome reputations for their extreme aggression; Guinness World Records certifies the ant Myrmecia pyriformis as the world's most dangerous ant. The jack jumper have been compared to other highly aggressive ant species, such as Brachyponera chinensis, Brachyponera sennaarensis, and the red imported fire ant (Solenopsis invicta). The retractable sting is located in their abdomen, attached to a single venom gland connected by the venom sac, which is where the venom is accumulated. Exocrine glands are known in jack jumpers, which produce the venom compounds later used to inject into their victims. Their venom contains haemolytic and eicosanoid elements and histamines. It contains a range of active ingredients and enzymatic activity, which includes phospholipase A2 and B, hyaluronidase, acid and alkaline phosphatase. The venom of the ant also contains several peptides; one being pilosulin 1, which causes cytotoxic effects, pilosulin 2, which has antihypertensive properties and pilosulin 3, which is known to be a major allergen. Other pilosulins include pilosulin 4 and pilosulin 5. The peptides have known molecular weights. The LD50 (lethal dose) occurs at a lower concentration than for melittin, a peptide found in bee venom. Its LD50 value is 3.6 mg/kg (injected intravenously in mice).

Loss of cell viability in the jack jumper's venom was researched through cytometry, which measures the proportions of cells that glow in the presence of fluorescent dye and 7-Aminoactinomycin D. Examinations of the rapidly reproducing Epstein–Barr B-cells showed that the cells lost viability within minutes when exposed to pilosulin 1. Normal white blood cells were also found to alter easily when exposed to pilosulin 1. However, partial peptides of pilosulin 1 were less efficient at lowering cell viability; the residue 22 N-terminal plays a critical role in the cytotoxic activity of pilosulin 1.

20 percent of jack jumper ants have an empty venom sac, so failure to display a sting reaction should not be interpreted as a loss of sensitivity. Substantial amounts of ant venom have been analysed to characterise venom components, and the jack jumper has been a main subject in these studies. An East Carolina University study which summarised the knowledge about ant stings and their venom showed that only the fire ant and jack jumper had the allergenic components of their venom extensively investigated. These allergenic components include peptides found as heterodimers, homodimers and pilosulin 3. Only six Myrmecia ants, including the jack jumper, are capable of inducing IgE antibodies. Due to the vast differentiation of venom produced in each Myrmecia species, and other species sharing similar characteristics to the jack jumper ant, diagnosing which ant is responsible for an anaphylactic reaction is difficult. A review of a patients history with allergies while identifying a positive result of venom specific IgE levels helps to identify the species of ant that caused a reaction.

Reactions to the ants sting show similar symptoms to fire ant stings; namely local swelling which lasts for several days, and swelling of the lips, face and eyes may occur from a minor allergic reaction. Other common symptoms include watering of the eyes and nose, and hives or welts will begin to develop. Headaches, anxiety and flushing may also occur. Jack jumpers, bees and wasps are the most common causes of anaphylaxis from insect stings. People most commonly feel a sharp pain after these stings, similar to that from an electric shock. Some patients develop a systemic skin reaction after being stung. Localised envenomation occurs with every sting, but severe envenoming only occurs if someone has been stung many times (as many as 50 to 300 stings in adults). The heart rate increases, and blood pressure falls rapidly. Most people will only experience mild skin irritation after being stung. Those who suffer from a severe allergic reaction will show a wide variety of symptoms. This includes difficulty breathing and talking, the tongue and throat will swell up, and coughing, chest tightness, abdominal pain, nausea and vomiting may occur. Others may lose consciousness and collapse (sometimes people may not collapse), and confusion. Children who get stung will show symptoms such as floppiness and paleness if a severe allergic reaction occurs.

In individuals allergic to the venom (about 2–3% of the population), a sting sometimes causes anaphylactic shock. In comparison to other insects such as the western honeybee (Apis mellifera) and the European wasp (Vespula germanica), their rates are only 1.4% and 0.6%. The annual sting exposure rates for the jack jumper ant, Western honeybee and European wasp are 12%, 7% and 2%. The median time from sting to cardiac arrest is 15 minutes, but the maximum period is around three hours. The ant allergy does not disappear; people with jack jumper allergies will most likely suffer from another allergic reaction if re-stung. Approximately 70 percent of patients with a history of systemic reaction to the ant's sting have another reaction when stung again. In comparison, systemic reaction figures for Apis mellifera and Vespula germanica after being stung show a rate of 50% and 25%. About half of these reactions were life-threatening and occurred predominantly in people who had had previous incidents with the sting. Anaphylaxis in jack jumper ant stings are not rare; 2.9% of 600 residents from semi-rural Victoria had allergic reactions to the ant's sting, according to a questionnaire. The sensitivity to stings is persistent for many years.

In 2011, an Australian ant allergy venom study was conducted, with the goal of determining which native Australian ants were associated with ant sting anaphylaxis. It showed that the jack jumper ant was responsible for the majority of patients' reactions to Myrmecia ant stings. Of the 265 patients who reacted to a sting from an ant belonging to the Myrmecia genus, 176 were from the jack jumper. 15 from M. nigrocincta and three from M. ludlowi, while 56 patients had reacted to other Myrmecia ants. The study concluded that four native species of Australian ants caused anaphylaxis. Apart from Myrmecia species, the green-head ant (Rhytidoponera metallica) was also responsible for several systemic reactions.

Most people recover uneventfully following a mild local reaction and up to about 3% of individuals suffer a severe localised reaction. Most individuals who suffer from severe localised reactions will most likely encounter another reaction if stung again. Fatalities are rare, and venom immunotherapy can prevent fatalities.


The flowering plant Carpobrotus glaucescens is useful to ease the pain from a sting
If no signs of an allergic reaction are present, an ice pack or commercially available sprays are used to relieve the pain. Stingose is also recommended to treat a jack jumper sting. Other treatments include washing the stung area with soap and water, and if continuous pain remains for several days, antihistamine tablets are taken for one to three days.

Emergency treatment is needed in a case of a severe allergic reaction. Before calling for help, laying a person down and elevating the legs is suggested. Depending on a patients needs, they will be given an EpiPen or an Anapen to use in case they are stung. In a scenario of experiencing anaphylaxis, further doses of adrenaline and intravenous infusions may be required. Some with severe anaphylaxis may suffer cardiac arrest and will need resuscitation. Inhalers may additionally be used in case a victim has asthma and experiences a reaction from a sting. The use of ACE inhibitors is not recommended, as it is known to increase the risk of anaphylaxis. Medications like antihistamines, H2 blockers, corticosteroids and anti-leukotrienes have no effect on anaphylaxis.

There are several bush remedies used to treat jack jumper stings (and any other Myrmecia sting). The young tips of a bracken fern provide a useful bush remedy to treat jack jumper stings, discovered and currently used by indigenous Australians. The tips are rubbed on the stung area, and may relieve the local pain after getting stung. Another plant used as a bush remedy is Carpobrotus glaucescens (known as angular sea-fig or pigface).


The Royal Hobart Hospital in Hobart, Tasmania offers a desensitisation program for people who are prone to severe anaphylactic reactions to jack jumper ant stings
Main article: Allergen immunotherapy
Desensitisation (also called allergy immunotherapy) to the jack jumper sting venom has shown effectiveness in preventing anaphylaxis, but the standardisation of jack jumper venom is yet to be validated. Unlike bee and wasp sting immunotherapy, jack jumper immunotherapy lacks funding and no government rebate is available. Venom is available; however, no commercial venom extract is available that can be used for skin testing. Venom extract is only available through the Therapeutic Goods Administration Special Access Scheme.

The Royal Hobart Hospital offers a desensitisation program for patients who have had a severe allergic reaction to a jack jumper sting. However, the program may face closure due to budget cuts. Professor Simon Brown, who founded the program, commented, "Closing the program will leave 300 patients hanging in the lurch". There is a campaign to make the program available in Victoria. The Royal Adelaide Hospital runs a small-scale program that desensitises patients to the ants venom.

Patients are given an injection of venom under the skin in small amounts. During immunotherapy, the first dose is small, but will gradually increase per injection. This sort of immunotherapy is designed to change how the immune system reacts to increased doses of venom entering the body.

Follow-ups of untreated people over thirty with a history of severe allergic reactions would greatly benefit from venom immunotherapy. Both rapid and slow doses can be done safely during immunotherapy. The efficacy (capacity to induce a therapeutic effect) of ant venom immunotherapy is effective in reducing systemic reactions in comparison to placebo and whole body extract immunotherapy, where patients were more likely to suffer from a systemic reaction. Ultrarush initiation of insect immunotherapy may be used, but results show higher risks of allergic reactions. Despite immunotherapy being successful, only ten percent of patients do not have any response to desensitisation.

It is suggested that people should avoid jack jumpers, but this is difficult to do. Closed footwear (boots and shoes) along with socks reduce the chances of encountering a sting, but wearing thongs or sandals will put the person at risk. With this said, they are still capable of stinging through fabric, and can find their way through gaps in clothing. Most stings occur when people are gardening, so taking extra caution or avoiding gardening altogether is recommended. People can also avoid encountering jack jumpers by moving to locations where jack jumper populations are either low or absent, or eliminate nearby nests. Since Myrmecia ants have different venoms, people who are allergic to them are advised to stay away from all Myrmecia ants, especially to ones they have not encountered before.




source - Wikipedia

Paraponera clavata is a species of ant, commonly known as the bullet ant, named on account of its powerful and potent sting due to its venom. It inhabits humid lowland rainforests from Nicaragua and the extreme east of Honduras and south to Paraguay.

Taxonomy


Paraponera dieteri (pictured) is the only known species that is closely related to Paraponera clavata
Paraponera clavata was first described by Danish zoologist Johan Christian Fabricius, who named it Formica clavata in his 1775 publication Systema entomologiae, based on a worker he collected. Fabricius incorrectly listed its type locality as India, although these ants are only found in South America. French zoologist Pierre André Latreille would later transfer the species to the genus Ponera in 1804. In 1858, the genus Paraponera was established by British entomologist Frederick Smith, who designated Paraponera clavata as the type species by monotypy (the condition of a taxonomic group having only a single taxon described). In this publication, Smith would synonymise multiple taxons under Paraponera clavata, including Formica armata, Formica spininoda, Ponera tarsalis and Ponera clavata. Later publications would also synonymise more taxons, including Formica aculeata and Formica clavata. Until 1994, Paraponera clavata was the sole member of the genus Paraponera and the subfamily Paraponerinae, but the extinct Paraponera dieteri from the Miocene was described by Cesare Baroni Urbani.

P. clavata is commonly known as the bullet ant, the lesser giant hunting ant and conga ant.

A local name is hormiga veinticuatro (the "24 ant" or "24-hour ant"), referring to the full day of pain that follows being stung. The specific epithet clavata means "club-shaped".

Description

Worker ants are 18–30 millimetres (0.7–1.2 in) long and resemble stout, reddish-black, wingless wasps. Paraponera is predatory, and like all primitive poneromorphs, does not display polymorphism in the worker caste; the queen ant is not much larger than the workers.


Paraponera clavata – museum specimen

Photograph demonstrating the size of bullet ants, with a 2-cm scale bar
Distribution and habitat

Paraponera is distributed throughout Central America and South America, commonly found in the wet neotropic ecozone. These ants are found in Honduras, Nicaragua and Costa Rica from the north, and in Venezuela, Colombia, Ecuador, Peru and Brazil from the south. Colonies are found in lowland areas, at elevations ranging from sea level to 750 metres (2,460 ft). However, specimens have been collected at elevations of 1,500 metres (4,920 ft) in Parque La Amistad.

Colonies consist of several hundred individuals and are usually situated at the bases of trees. Workers forage arboreally in the area directly above the nest for small arthropods and nectar, often as far as the upper canopy; little foraging occurs on the forest floor. Nectar, carried between the mandibles, is the most common food taken back to the nest by foragers. Two studies in Costa Rica and on Barro Colorado Island (BCI) found about four bullet ant nests per hectare of forest. On BCI, the nests were found under 70 species of trees, six species of shrubs, two species of lianas and one species of palm. Nests were most common beneath the canopies of Faramea occidentalis and Trichilia tuberculata, but these trees are also the most abundant in the forest. Nests were present more frequently than would be expected based on the abundance of the trees under Alseis blackiana, Tabernaemontana arborea, Virola sebifera, Guaria guidonia and Oecocarpus mapoura. The large number of nest plants suggests little active selection of nest sites by bullet ants. Small shrubs, however, are underused, probably because they do not provide access to the forest canopy. The study on BCI concluded trees with buttresses and extrafloral nectaries may be selected for by bullet ants.

Parasites

The small (1.5– to 2.0-mm-long) phorid fly, Apocephalus paraponerae, is a parasite of injured workers of P. clavata, of which the supply is constant because frequent aggressive encounters occur between neighbouring colonies, resulting in maimed workers. The flies are able to parasitise healthy ants if the ants are artificially restrained, but healthy ants are agile and able to repel them. Both male and female flies are attracted by the scent of injured ants; the females lay eggs, as well as feed, and the males feed and possibly mate with the females. The flies are attracted to a crushed ant within two to three minutes and 10 or more flies may be attracted to each ant. Each ant can harbour 20 fly larvae. Carl Rettenmeyer observed P. clavata actively trying to attack A. paraponerae when they approached the entrance to their nest.

Relationship with humans

The pain caused by this insect's sting is reported to be greater than that of any other hymenoptera, and is ranked as the most painful according to the Schmidt sting pain index, given a "4+" rating, above the tarantula hawk wasp and, according to some victims, equal to being shot, hence the name of the insect. It is described as causing "waves of burning, throbbing, all-consuming pain that continues unabated for up to 24 hours". The sting is considered to be an effective defence against predators. Poneratoxin, a paralyzing neurotoxic peptide isolated from the venom, affects voltage-dependent sodium ion channels and blocks the synaptic transmission in the central nervous system. It is being investigated for possible medical applications.

The Sateré-Mawé people of Brazil use intentional bullet ant stings as part of their initiation rites to become a warrior. The ants are first rendered unconscious by submerging them in a natural sedative, and then hundreds of them are woven into gloves made of leaves (which resembles a large oven mitt), stingers facing inward. When the ants regain consciousness, a boy slips the gloves onto his hands. The goal of this initiation rite is to keep the glove on for a full 10 minutes. When finished, the boy's hand and part of his arm are temporarily paralyzed because of the ant venom, and he may shake uncontrollably for days. The only "protection" provided is a coating of charcoal on the hands, supposedly to confuse the ants and inhibit their stinging. To fully complete the initiation, however, the boys must go through the ordeal a total of 20 times over the course of several months or even years.


source - Wikipedia

The inchman (Myrmecia forficata) is a species of bull ant that is native to Australia. The ants are recorded in the south eastern part of the country, but are most often found in Tasmania.[citation needed]

The inchman is the most venomous of the bulldog ants, ranging from about 15 to 25 mm (0.6 to 1.0 in) long, but less aggressive than the Jack jumper ant. These ants are purplish-brown, with a black abdomen. Their large size gave them their name, although most are slightly smaller than the traditional inch (25.4 mm). Their nests may be inconspicuously hidden under a rock or in a small hole.[citation needed]

As with many species of bulldog ants, the inchman are usually solitary when they forage, though they live in colonies like most ants. Inchman are carnivores and scavengers. They sting their victims with venom analogous to stings of wasps, bees, and fire ants. Their venom is some of the most powerful in the insect world. The reputation for being the most venomous ant is possibly due to the tendency of the toxin to induce anaphylaxis. It is this which kills the victim.[citation needed]

The symptoms of the stings of the ants are similar to stings of the fire ants. The reaction is local; swelling, reddening and fever, followed by formation of a blister. The heart rate increases, and blood pressure falls rapidly. In about 3% of cases, the sting causes anaphylaxis. Treatment is very similar to wasp and bee stings.[citation needed]


source - Wikipedia

The red bull ant (Myrmecia gulosa), also known as the giant bull ant or "hoppy joe", is a species of bulldog ant from the genus Myrmecia. It is abundant throughout Eastern Australia.

Taxonomy

The first Myrmecia gulosa specimen was collected in 1770 by Joseph Banks, making it one of the first Australian insects to be collected and described.

Description

As one of the largest of ant species, adult individuals have been observed to be as long as 15 mm to 30 mm in body length. The head and thorax are typically coloured red-brown; the rear half of the abdomen is black and the mandibles brown-yellow. Adults characteristically possess the long, powerful serrated mandibles and a venom-laced sting capable of causing severe pain for a couple of days. Unlike most other ant species, red bull ants lack the ability of chemical senses; however, this is compensated by their extremely keen vision, with which they can spot and respond to intruders two metres away.

Distribution and habitat

M. gulosa ants are abundant in eastern Australia. They can be found in the coastal regions of Queensland and east of New South Wales. Populations can be found Australian Capital Territory and in the Murray-Darling Basin. Colonies of M. gulosa ants have been recorded from Black Mountain, Brisbane, Fletcher, Stanthorpe and St. George in Queensland, and in New South Wales they have been recorded in Lismore, Armidale, Narrabri, Clarence River, Taree and in Sydney (in the suburbs of Como, Oatley and Liverpool).

Their distribution in Victoria, Tasmania, South Australia, Northern Territory and Western Australia has not yet been verified. Based on specimens collected, they are found living in elevations ranging from 121 - 3,000 meters (396 ft - 9,842 ft). M. gulosa ants generally construct small mounds, and they prefer open areas where they are frequently seen foraging. Foraging workers are frequently observed being around burnt areas.

Behaviour

Regarded as a relatively "primitive" ant species, red bull ants are known to be solitary predators that are occasionally uncooperative with one another, whose social behaviour is poorly developed in comparison to more "advanced" species. They are notoriously aggressive hunters able to subdue formidable prey such as bees and other ants. Unable to eat solid food, adult ants feed on juices from the prey insects; the meat of the prey is fed to the colony's larvae. Their diet is supplemented by the workers' own trophic (infertile) eggs, which are commonly fed to the queen and larvae.

Nests are constructed underground; tunnel systems may become quite extensive.

External images

Wikimedia Commons has media related to Myrmecia gulosa.
Myrmecia gulosa - Antweb

source - Wikipedia

Pogonomyrmex badius, or the Florida harvester ant, is a species of harvester ant in the genus Pogonomyrmex. It is the only Pogonomyrmex species found on the east coast of the United States.


source - Wikipedia