''Monomorium'' is a genus of

ant Ants are Eusociality, eusocial insects of the Family (biology), family Formicidae and, along with the related wasps and bees, belong to the Taxonomy (biology), order Hymenoptera. Ants evolved from Vespoidea, vespoid wasp ancestors in the Cre ...

s in the subfamily

Myrmicinae Myrmicinae is a subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily ...

. As of 2013 it contains about 396 species. It is distributed around the world, with many species native to the

Old World The "Old World" () is a term for Afro-Eurasia coined by Europeans after 1493, when they became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia in the Eastern Hemisphere, previously ...

tropics The tropics are the regions of Earth surrounding the equator, where the sun may shine directly overhead. This contrasts with the temperate or polar regions of Earth, where the Sun can never be directly overhead. This is because of Earth's ax ...

. It is considered to be "one of the more important groups of ants," considering its widespread distribution, its diversity, and its variety of morphological and biological characteristics. It also includes several familiar pest species, such as the

pharaoh ant The pharaoh ant (''Monomorium pharaonis'') is a small (2 mm) yellow or light brown, almost transparent ant notorious for being a major indoor nuisance pest, especially in hospitals. A cryptogenic species, it has now been introduced to vir ...

(''M. pharaonis'') and the flower ant (''M. floricola'').

Description

This genus is very diverse in morphology, with species of many shapes and sizes that "do not necessarily even remotely resemble one another" at first glance. In certain species, the worker caste is monomorphic, whereas in others, it is polymorphic. In some species the workers are minute, in others they are rather large. Large, multifaceted eyes are common, but ''M. inusuale'' has much reduced eyes, as do some species from Africa. The sting is always functional.Fernández, F. (2007). Two new South American species of ''Monomorium'' Mayr with taxonomic notes on the genus. ''In:'' Snelling, R. R., et al. (eds). Advances in ant systematics (Hymenoptera: Formicidae): homage to

E. O. Wilson Edward Osborne Wilson (June 10, 1929 – December 26, 2021) was an American biologist, naturalist, ecologist, and entomologist known for developing the field of sociobiology. Born in Alabama, Wilson found an early interest in nature and frequ ...

– 50 years of contributions. ''Memoirs of the American Entomological Institute'' 80, 128-45.

Taxonomy

By the early 20th century ''Monomorium'' was already a large genus, with 10 subgenera. It was further expanded in 2007, when the genera ''Nothidris'', ''Epelysidris'', and ''Phacota'' were synonymized with ''Monomorium''. The small genera ''

Anillomyrma ''Anillomyrma'' is an Asian genus of ants in the subfamily Myrmicinae. Distribution and habitat Its two species are distributed in south, southeast and East Asia. ''A. decamera'' is known from Sri Lanka, India, Vietnam and China, and ''A. trid ...

'', ''

Megalomyrmex ''Megalomyrmex'' is a genus of ant in the subfamily Myrmicinae. The genus is known only from the Neotropics, where some of the species are specialized parasites or predators of Attini. Description It is difficult to characterize morphologicall ...

'', and perhaps '' Bondroita'' should possibly also be included in ''Monomorium''. The exact boundaries of the genus are still to be determined: it has no distinct morphological traits that set it apart from other genera in the tribe

Solenopsidini Solenopsidini (meaning "pipe-faced") is a tribe of myrmicine ants with about 20 genera. Genera *'' Adelomyrmex'' *'' Anillomyrma'' *'' Austromorium'' *'' Baracidris'' *'' Bariamyrma'' *'' Bondroitia'' *'' Chelaner'' *'' Cryptomyrmex'' ...

. If

cladistics Cladistics ( ; from Ancient Greek 'branch') is an approach to Taxonomy (biology), biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesiz ...

were strictly applied, all Solenopsidini would be grouped in the single genus '' Solenopsis'', but the tribe lacks a strong

synapomorphy In phylogenetics, an apomorphy (or derived trait) is a novel Phenotypic trait, character or character state that has evolution, evolved from its ancestral form (or Plesiomorphy and symplesiomorphy, plesiomorphy). A synapomorphy is an apomorphy sh ...

. As with the genera ''

Camponotus Carpenter ants (''Camponotus'' spp.) are a genus of large ants (workers ) indigenous to many parts of the world. True carpenter ants build nests inside wood, consisting of galleries chewed out with their mandibles or jaws, preferably in dead, ...

'' and ''

Leptothorax ''Leptothorax'' is a genus of small ants with mainly Holarctic distributions. The genus is notable for its widespread social parasitism, i.e. they are dependent on the help of workers from other ant species during a part or the whole of their lif ...

,'' ''Monomorium'' as it currently stands is

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

. Subsequent studies using molecular techniques have suggested ways to break up the genus. A 2015 study resurrected the previously synonymised genus ''

Syllophopsis ''Syllophopsis'' is a genus of Myrmicine ants found across the Southern Hemisphere and the tropics except South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a cons ...

'' (including '' Ireneidris'') from within ''Monomorium''. ''

Epelysidris ''Epelysidris brocha'' is the only species of ant in the genus ''Epelysidris''. Described by Barry Bolton in 1987 in Borneo Borneo () is the List of islands by area, third-largest island in the world, with an area of , and population of 23 ...

'' was also resurrected to contain the species '' E. brocha.'' In 2019 the genus '' Chelaner'' was resurrected for 53 Australasian and Pacific species, including the common New Zealand species '' Chelaner antipodum''.

Biology

Most ants of this genus nest in rotting wood, under rocks, or in the soil. Some species are

scavenger Scavengers are animals that consume Corpse decomposition, dead organisms that have died from causes other than predation or have been killed by other predators. While scavenging generally refers to carnivores feeding on carrion, it is also a he ...

s, while others are seed collectors. Many species have

venom Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

containing

alkaloid Alkaloids are a broad class of natural product, naturally occurring organic compounds that contain at least one nitrogen atom. Some synthetic compounds of similar structure may also be termed alkaloids. Alkaloids are produced by a large varie ...

s, which they use as a defense from predators. Besides its morphological variation, the genus is also variable in

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

number, with 2''n'' of 16 to 70 recorded.

Distribution

As of 2006, 36 species are described from

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

, 19 of which were described in that year alone. About 43 species are known from Australia and 30 from

Arabia The Arabian Peninsula (, , or , , ) or Arabia, is a peninsula in West Asia, situated north-east of Africa on the Arabian plate. At , comparable in size to India, the Arabian Peninsula is the largest peninsula in the world. Geographically, the ...

Selected species

* '' Monomorium antarcticum'' * ''

Monomorium bidentatum ''Monomorium bidentatum'' is a species of ant in the subfamily Myrmicinae. It is Endemism, endemic to two South American countries, Chile and Argentina. Description Workers are around long. The general color is dark brown, with the mandibles, a ...

'' * '' Monomorium chinense'' * '' Monomorium carbonarium'' – little black ant * '' Monomorium delabiei'' Fernández, 2007 * '' Monomorium dentatum'' * '' Monomorium denticulatum'' * ''

Monomorium effractor ''Monomorium effractor'' is a species of ant in the genus ''Monomorium''. It is native to India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest ...

'' * '' Monomorium fieldi'' * ''

Monomorium floricola The bicolored trailing ant or flower ant (''Monomorium floricola'') is a species of ant of the subfamily Myrmicinae Myrmicinae is a subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) ...

'' – flower ant * ''

Monomorium hospitum ''Monomorium hospitum'' is a species of ant in the genus '' Monomorium''. It is native to Singapore Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory compri ...

'' * ''

Monomorium inquilinum ''Monomorium'' is a genus of ants in the subfamily Myrmicinae. As of 2013 it contains about 396 species. It is distributed around the world, with many species native to the Old World tropics. It is considered to be "one of the more important grou ...

'' * '' Monomorium kondratieffi'' Sharaf & Aldawood, 2013 * ''

Monomorium monomorium ''Monomorium'' is a genus of ants in the subfamily Myrmicinae. As of 2013 it contains about 396 species. It is distributed around the world, with many species native to the Old World tropics. It is considered to be "one of the more important grou ...

'' Bolton, 1987 (= ''Mononorium minutum'' Mayr, 1855) * ''

Monomorium noualhieri ''Monomorium noualhieri'' is a species of ant Endemism, endemic to Algeria. References

Insects of North Africa Monomorium, noualhieri Hymenoptera of Africa Insects described in 1895 Endemic fauna of Algeria Taxonomy articles created by ...

'' * '' Monomorium pergandei'' * ''

Monomorium pharaonis The pharaoh ant (''Monomorium pharaonis'') is a small (2 mm) yellow or light brown, almost transparent ant notorious for being a major indoor nuisance pest (animal), pest, especially in hospitals. A cryptogenic species, it has now been intr ...

'' – pharaoh ant * '' Monomorium rubriceps'' * '' Monomorium santschii'' * '' Monomorium smithi'' * '' Monomorium talbotae''

References

External links

''Monomorium''.
Japanese Ant Image Database. {{Authority control Ant genera Taxa named by Gustav Mayr Taxonomy articles created by Polbot