Gaster (insect anatomy)

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In the worker ant the metasoma is divided into the narrow petiole and bulbous gaster. The abdomen technically includes the metasoma and the propodeum which is fused to the thorax. Scheme ant worker anatomy-en.svg
In the worker ant the metasoma is divided into the narrow petiole and bulbous gaster. The abdomen technically includes the metasoma and the propodeum which is fused to the thorax.

The gaster is the bulbous posterior portion of the metasoma found in hymenopterans of the suborder Apocrita (bees, wasps and ants). This begins with abdominal segment III on most ants, but some make a constricted postpetiole out of segment III, in which case the gaster begins with abdominal segment IV. [1] [2]

Certain ants in the genus Cataglyphis , including Cataglyphis bicolor and Cataglyphis fortis , have a cubiform petiole that allows them to decrease their inertia (and therefore increase their speed) by raising their gaster into an upright position. [3]

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<span class="mw-page-title-main">Ant</span> Family of insects

Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of 22,000 species have been classified. They are easily identified by their geniculate (elbowed) antennae and the distinctive node-like structure that forms their slender waists.

<span class="mw-page-title-main">Hymenoptera</span> Order of insects comprising sawflies, wasps, bees, and ants

Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typically have a special ovipositor for inserting eggs into hosts or places that are otherwise inaccessible. This ovipositor is often modified into a stinger. The young develop through holometabolism — that is, they have a wormlike larval stage and an inactive pupal stage before they reach adulthood.

<i>Tapinoma melanocephalum</i> Species of ant

Tapinoma melanocephalum is a species of ant that goes by the common name ghost ant. They are recognised by their dark head and pale or translucent legs and gaster (abdomen). This colouring makes this tiny ant seem even smaller.

<span class="mw-page-title-main">Abdomen</span> Part of the body between the chest and pelvis

The abdomen is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. The area occupied by the abdomen is called the abdominal cavity. In arthropods, it is the posterior tagma of the body; it follows the thorax or cephalothorax.

<span class="mw-page-title-main">Mesosoma</span> Anthropod body part

The mesosoma is the middle part of the body, or tagma, of arthropods whose body is composed of three parts, the other two being the prosoma and the metasoma. It bears the legs, and, in the case of winged insects, the wings.

<span class="mw-page-title-main">Banded sugar ant</span> Species of carpenter ant (Camponotus consobrinus)

The banded sugar ant, also known as the sugar ant, is a species of ant native to Australia. A member of the genus Camponotus in the subfamily Formicinae, it was described by German entomologist Wilhelm Ferdinand Erichson in 1842. Its common name refers to the ant's liking for sugar and sweet food, as well as the distinctive orange-brown band that wraps around its gaster.

<i>Nothomyrmecia</i> Genus of ants

Nothomyrmecia, also known as the dinosaur ant or dawn ant, is an extremely rare genus of ants consisting of a single species, Nothomyrmecia macrops. These ants live in South Australia, nesting in old-growth mallee woodland and Eucalyptus woodland. The full distribution of Nothomyrmecia has never been assessed, and it is unknown how widespread the species truly is; its potential range may be wider if it does favour old-growth mallee woodland. Possible threats to its survival include habitat destruction and climate change. Nothomyrmecia is most active when it is cold because workers encounter fewer competitors and predators such as Camponotus and Iridomyrmex, and it also increases hunting success. Thus, the increase of temperature may prevent them from foraging and very few areas would be suitable for the ant to live in. As a result, the IUCN lists the ant as Critically Endangered.

<span class="mw-page-title-main">Queen ant</span> Adult reproducing ant in an ant colony

A queen ant is an adult, reproducing female ant in an ant colony; she is usually the mother of all the other ants in that colony. Some female ants, such as the Cataglyphis, do not need to mate to produce offspring, reproducing through asexual parthenogenesis or cloning, and all of those offspring will be female. Others, like those in the genus Crematogaster, mate in a nuptial flight. Queen offspring ants among most species develop from larvae specially fed in order to become sexually mature.

<i>Cataglyphis</i> Genus of ants

Cataglyphis is a genus of ant, desert ants, in the subfamily Formicinae. Its most famous species is C. bicolor, the Sahara Desert ant, which runs on hot sand to find insects that died of heat exhaustion, and can, like other several other Cataglyphis species, sustain body temperatures up to 50°C. Cataglyphis is also the name of an autonomous rover that won the NASA Sample Return Robot Centennial Challenge inspired by the navigation approaches used by desert ants.

<i>Sphecomyrma</i> Extinct genus of ants

Sphecomyrma is an extinct genus of ants which existed in the Cretaceous approximately 79 to 92 million years ago. The first specimens were collected in 1966, found embedded in amber which had been exposed in the cliffs of Cliffwood, New Jersey, by Edmund Frey and his wife. In 1967, zoologists E. O. Wilson, Frank Carpenter and William L. Brown, Jr. published a paper describing and naming Sphecomyrma freyi. They described an ant with a mosaic of features—a mix of characteristics from modern ants and aculeate wasps. It possessed a metapleural gland, a feature unique to ants. Furthermore, it was wingless and had a petiole which was ant-like in form. The mandibles were short and wasp-like with only two teeth, the gaster was constricted, and the middle and hind legs had double tibial spurs. The antennae were, in form, midway between the wasps and ants, having a short first segment but a long flexible funiculus. Three additional species, S. canadensis, S. mesaki and S. nexa, were described in 1985, 2005, and 2024, respectively.

<i>Diaphoromyrma</i> Genus of ants

Diaphoromyrma is a genus of ants in the subfamily Myrmicinae. It contains the single species Diaphoromyrma sofiae, known only from workers from the type locality in Bahia, Brazil. The genus is apparently close to Allomerus and Diplomorium in the Solenopsidini, but its tribal attribution remains uncertain.

<i>Leptanilla japonica</i> Species of ant

Leptanilla japonica is an uncommon highly migratory, subterranean ant found in Japan. They are tiny insects, with workers measuring about 1.2 mm and queens reaching to about 1.8 mm, and live in very small colonies of only a few hundred individuals at a time Its sexual development follows a seasonal cycle that affects the colony's migration and feeding habits, and vice versa. L. japonica exhibits specialized predation, with prey consisting mainly of geophilomorph centipedes, a less reliable food source that also contributes to their high rate of nest migration. Like ants of genera Amblyopone and Proceratium, the genus Leptanilla engages in larval hemolymph feeding (LHF), with the queen using no other form of sustenance. LHF is an advantageous alternative to the more costly cannibalism. Unlike any other ant, however, members of Leptanilla, including L. japonica, have evolved a specialized organ dubbed the “larval hemolymph tap” that reduces the damage LHF inflicts on the larvae. LHF has become this species' main form of nutrition.

<i>Titanomyrma</i> Extinct genus of ants

Titanomyrma is a genus of extinct giant ants which lived during the Eocene. The type species Titanomyrma gigantea and the smaller Titanomyrma simillima are known from the Eocene of Germany, while the third species Titanomyrma lubei, is known from Wyoming, United States. The presence of Titanomyrma in North America was considered to indicate "the first reported cross-Arctic dispersal by a thermophilic insect group".. However a queen reported from Upland temperate shales in British Columbia raised questions on the exact thermophilic nature of the genus. The type species of this genus, T. gigantea, is the largest-known fossil or extant species of ant in the world.

<i>Kollasmosoma sentum</i> Species of wasp

Kollasmosoma sentum is a parasitoid wasp in the family Braconidae, which lays its eggs inside adult ants. It was featured as one of "the top 10 new species of 2012" in a list compiled by Conservationists at the Arizona State University International Institute for Species Exploration.

<span class="mw-page-title-main">Agroecomyrmecinae</span> Subfamily of ants

Agroecomyrmecinae is a subfamily of ants containing two extant and two fossil genera. The subfamily was originally classified in 1930 by Carpenter as Agroecomyrmecini, a Myrmicinae tribe. Bolton raised the tribe to subfamily status in 2003, suggesting that Agroecomyrmecinae might be the sister taxon to Myrmicinae. It has since been discovered to be one of the earliest lineages of ants, a clade from the basal polytomy for all ants. In 2014, the subfamily was expanded to two tribes. The tribe Ankylomyrmini was moved from the subfamily Myrmicinae to Agroemyrmecinae.

<i>Archimyrmex</i> Extinct genus of ants

Archimyrmex is an extinct genus of ant in the formicid subfamily Myrmeciinae, described by palaeoentomologist Theodore Cockerell in 1923. The genus contains four described species, Archimyrmex rostratus, Archimyrmex piatnitzkyi, Archimyrmex smekali and Archimyrmex wedmannae. Archimyrmex is known from a group of Middle Eocene fossils which were found in North America, South America, and Europe. The genus was initially placed in the subfamily Ponerinae, but it was later placed in Myrmeciinae; it is now believed to be the ancestor of the extant primitive genus Myrmecia from Australia. Despite this, Archimyrmex is not a member to any tribe and is regarded as incertae sedis within Myrmeciinae. However, some authors believe Archimyrmex should be assigned as incertae sedis within Formicidae. These ants can be characterised by their large mandibles and body length, ranging from 13.2 to 30 mm. They also have long, thin legs and an elongated mesosoma (thorax) and petiole.

<i>Yantaromyrmex</i> Genus of ants

Yantaromyrmex is an extinct genus of ants first described in 2013. Members of this genus are in the subfamily Dolichoderinae of the family Formicidae, known from Middle Eocene to Early Oligocene fossils found in Europe. The genus currently contains five described species, Y. constrictus, Y. geinitzi, Y. intermedius, Y. mayrianum and Y. samlandicus. The first specimens were collected in 1868 and studied by Austrian entomologist Gustav Mayr, who originally placed the fossils in other ant genera until the fossils were reviewed and subsequently placed into their own genus. These ants are small, measuring from 4 to 6 mm in length and can be characterized by their trapezoidal shaped head-capsules and oval compound eyes that are located slightly to the rear of the capsules midpoint, with no known ocelli present.

<i>Gerontoformica</i> Extinct genus of ants

Gerontoformica is an extinct genus of stem-group ants. The genus contains thirteen described species known from Late Cretaceous fossils found in Asia and Europe. The species were described between 2004 and 2016, with a number of the species formerly being placed into the junior synonym genus Sphecomyrmodes.

Cataglyphis tartessica is an ant species of the genus Cataglyphis, it is endemic to Spain, mostly Western Andalucia, in the provinces of Huelva, Seville and Cadiz.

<i>Cataglyphis nigra</i> Species of ant

Cataglyphis nigra, also known as the black desert ant, is a species of ant in the genus Cataglyphis.

References

  1. "Ant Information". Insected.arizona.edu. Archived from the original on 2014-10-07. Retrieved 2014-08-20.
  2. "Notes from Underground-members". Desertants.org. Archived from the original on 2013-05-17. Retrieved 2014-08-20.
  3. McMeeking, Robert M .; Arzt, Eduard; Wehner, Rüdiger (July 2011). "Cataglyphis desert ants improve their mobility by raising the gaster". Journal of Theoretical Biology. 297: 17–25. doi:10.1016/j.jtbi.2011.12.003. PMID   22178639.