Oecophylla smaragdina

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Oecophylla smaragdina
Red Weaver Ant, Oecophylla smaragdina.jpg
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Formicinae
Genus: Oecophylla
O. smaragdina
Binomial name
Oecophylla smaragdina
Fabricius, 1775 [1]
Oecophylla range map.png
Oecophylla range map. O. longinoda in blue, O. smaragdina in red. [1]

Oecophylla smaragdina (common names include Asian weaver ant, weaver ant, green ant, green tree ant, semut rangrang, semut kerangga, and orange gaster) is a species of arboreal ant found in tropical Asia and Australia. These ants form colonies with multiple nests in trees, each nest being made of leaves stitched together using the silk produced by the ant larvae: hence the name 'oecophylla' [Greek for 'leaf-house'].



Workers and major workers are mostly coloured orange. Workers are 5–6 millimetres (0.20–0.24 in) long; they look after larvae and farm scale bugs for honeydew. Major workers are 8–10 millimetres (0.3–0.4 in) long, with long strong legs and large mandibles. They forage, assemble and expand the nest. Queens are typically 20–25 millimetres (0.8–1.0 in) long, and normally greenish-brown, giving the species its name smaragdina (Latin: emerald). [2]

Distribution and habitat

Oecophylla smaragdina has a widespread distribution in tropical Asia and Australia, its range extending from India through Indonesia and the Philippines to Northern Territory and Queensland in Australia. It is an arboreal species, making its nests among the foliage of trees. Nests are constructed during the night, with major workers weaving towards the exterior and minor workers completing the interior structure. [3] The ant colony may have several nests in one tree, or the nests may be spread over several adjacent trees; colonies can reach up to half a million individuals. [2] In one instance, a colony occupied 151 nests distributed among twelve trees. Each colony has a single queen, in one of these nests, and her progeny are carried to other nests of the colony. [4] The average life of a mature colony may be eight years. [3]


Weaver ants of this species are important parts of the ecosystem in tree canopies in humid tropical regions. [5] The nests of this species are constructed by the workers, with leaves being woven together and secured by silk produced by the larvae. First a row of ants line up along the edge of a green leaf and, grasping a nearby leaf, pull the two leaves together, edge to edge. Other workers on the far side of the leaves, each carrying a larva in its mouth, apply the tips of the abdomens of the larvae to each leaf edge in turn. This produces a suture of fine silken threads that secures the leaves together. More leaves are attached in a similar manner to enlarge the nest. [6]

Weaver ants feed on insects and other invertebrates, their prey being mainly beetles, flies and hymenopterans. [4] They do not sting, but have a painful bite into which they can secrete irritant chemicals from their abdomens. In the Oecophylla smaragdina, the antennal lobe glomeruli is seen in clusters, this appears to be a common feature in many Hymenopterans such as ants and honeybees [7] . In Singapore, colonies are often found in sea hibiscus and great morinda trees which entice the ants with nectar, the trees in return receiving protection from herbivorous insects. [8] In Indonesia, the trees supporting colonies include banana, coconut, oil palm, rubber tree, cacao, teak, jackfruit, mango, Chinese laurel, petai, jengkol, duku, rambutan, jambu air and kedondong. [4]

The ants also attend aphids, scale insects and other homopterans to feed on the honeydew they produce, especially in tree canopies linked by lianas. For this purpose, they drive away other ant species from the parts of the canopy where these sap-sucking insects live. [5] Another association is with the larvae of certain blue butterflies In Australia, the common oak-blue, the bright oak-blue and the purple oak-blue are obligate associates and only occur in parts of the country where the weaver ant is established. [9] Shelters may be built by the ants close to their nests specially to protect these assets. [5]

Some species of jumping spiders, such as myrmecophilic associate Cosmophasis bitaeniata , prey on the green tree ants by mimicking them with deceptive chemical scents. This is an example of Aggressive mimicry. Disguised as one of them, the jumping spiders access their nests to consume the larvae and lay their own eggs alongside the nest, so that spiderlings can easily reach the ant larvae. [3] The jumping spider Myrmaplata plataleoides is a batesian mimic of this species. This spider visually mimics this ant, via contracted body parts to create the illusion of a hymenopteran body structure. It also has two black spots to mimic eyes on the side of its head. This spider also steals the ant's brood to obtain the scent of the colony. Despite this, they generally steer clear of weaver ant nests.


Weaver ants can bite humans when disturbed. Angkor Wat, Cambodia Oecophylla smaragdina-biting.jpg
Weaver ants can bite humans when disturbed. Angkor Wat, Cambodia

The larvae and pupae are collected and processed into bird food and fish bait in Indonesia, [10] are used in Chinese and Indian traditional medicine, and consumed as a delicacy in Thailand and other countries. [11]

In Java, Indonesia the larvae and pupae of these ants are known as kroto and are harvested commercially for use as captive songbird food and as fishing bait. Songbirds are very popular in Java and the ant larvae provide a good balanced diet of proteins, minerals and vitamins. Kroto can be bought from pet shops or can be gathered fresh from the countryside. As bait for fish, the larvae are mixed with chicken eggs, maize, beans and honey. [4]

In some parts of India, the adult ants are used in traditional medicine as a remedy for rheumatism, and an oil made from them is used for stomach infections and as an aphrodisiac. In Thailand and the Philippines the larvae and pupae are eaten and are said to have a taste variously described as creamy, sour and lemony. [4]

In some parts of this ant's range, colonies are used as a natural form of pest control. Crops that have been protected in this way have included cowpea, [12] cashew, citrus, mango, coconut, cocoa and coffee. [13] The oldest written record of the use of these ants to control pests is their use in China in 304 AD to control pests in citrus. [13]

The ants are aggressive towards humans, and in Sri Lanka ant protection has been abandoned in coffee culture, because picking the crop proved too "painful". [4]

Related Research Articles

Ant 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, and diversified after the rise of flowering plants. 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.

Yellow crazy ant Species of ant (Anoplolepis gracilipes)

The yellow crazy ant(Anoplolepis gracilipes), also known as the long-legged ant or Maldive ant, is a species of ant, thought to be native to West Africa or Asia. They have been accidentally introduced to numerous places in the world's tropics.

Texas leafcutter ant Species of ant

Atta texana is a fungus-farming ant species of the genus Atta, found in Texas, Louisiana, and northeastern states of Mexico. Common names include town ant, parasol ant, fungus ant, Texas leafcutter ant, cut ant, and night ant. It harvests leaves from over 200 plant species, and is considered a major pest of agricultural and ornamental plants, as it can defoliate a citrus tree in less than 24 hours. Every colony has several queens and up to 2 million workers. Nests are built in well-drained, sandy or loamy soil, and may reach a depth of 6 m (20 ft), have 1000 entrance holes, and occupy 420 m2 (4,500 sq ft).

Weaver ant Genus of ants

Weaver ants or green ants are eusocial insects of the family Formicidae. Weaver ants live in trees and are known for their unique nest building behaviour where workers construct nests by weaving together leaves using larval silk. Colonies can be extremely large consisting of more than a hundred nests spanning numerous trees and containing more than half a million workers. Like many other ant species, weaver ants prey on small insects and supplement their diet with carbohydrate-rich honeydew excreted by small insects (Hemiptera). Weaver ant workers exhibit a clear bimodal size distribution, with almost no overlap between the size of the minor and major workers. The major workers are approximately 8–10 mm (0.31–0.39 in) in length and the minors approximately half the length of the majors. Major workers forage, defend, maintain, and expand the colony whereas minor workers tend to stay within the nests where they care for the brood and 'milk' scale insects in or close to the nests.

Carpenter ant Genus of ants (Camponotus spp.)

Carpenter ants are large ants indigenous to many forested parts of the world.

Pharaoh ant Species of ant

The pharaoh ant is a small (2 mm) yellow or light brown, almost transparent ant notorious for being a major indoor nuisance pest, especially in hospitals. The pharaoh ant, a cryptogenic species, has now been introduced to virtually every area of the world, including Europe, the Americas, Australasia and Southeast Asia. It is a major pest in the United States, Australia, and Europe.

<i>Atta sexdens</i> Species of ant

Atta sexdens is a species of leafcutter ant belonging to the tribe Attini, native to the New World, from the southern United States (Texas) to northern Argentina. They are absent from Chile. They cut leaves to provide a substrate for the fungus farms which are their principal source of food. Their societies are among the most complex found in social insects. A. sexdens is an ecologically important species, but also an agricultural pest. Other Atta species, such as Atta texana, Atta cephalotes and others, have similar behavior and ecology.

Eucharitidae Family of wasps

The Eucharitidae are a family of parasitic wasps. Eucharitid wasps are members of the superfamily Chalcidoidea and consist of three subfamilies: Oraseminae, Eucharitinae, and Gollumiellinae. Most of the 55 genera and 417 species of Eucharitidae are members of the subfamilies Oraseminae and Eucharitinae, and are found in tropical regions of the world.

<i>Myrmaplata plataleoides</i> Species of spider

Myrmaplata plataleoides, also called the Red Weaver-ant mimicking jumper, is a jumping spider that mimics the Asian weaver ant in morphology and behaviour. This species is found in India, Sri Lanka, China and many parts of Southeast Asia.

<i>Nothomyrmecia</i> Genus of ants

Nothomyrmecia, also known as the dinosaur ant or dawn ant, is a 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.

Meat ant Species of ant

The meat ant, also known as the gravel ant or southern meat ant, is a species of ant endemic to Australia. A member of the genus Iridomyrmex in the subfamily Dolichoderinae, it was described by British entomologist Frederick Smith in 1858. The meat ant is associated with many common names due to its appearance, nest-building behaviour and abundance, of which its specific name, purpureus, refers to its coloured appearance. It is among the best-known species of ant found throughout Australia; it occurs in almost all states and territories except for Tasmania. Its enormous distribution, aggression and ecological importance have made this ant a dominant species.

<i>Solenopsis molesta</i> Species of ant

Solenopsis molesta is the best known species of Solenopsisthief ants. They get their names from their habit of nesting close to other ant nests, from which they steal food. They are also called grease ants because they are attracted to grease. Nuptial flight in this species occur from late July through early fall.

<i>Technomyrmex albipes</i> Species of ant

Technomyrmex albipes, commonly known as the white-footed ant, is a species of ant first described in 1861 from Sulawesi, Indonesia by the British entomologist Frederick Smith. Invasive pest ants in Florida, previously identified as T. albipes, have now been separated as Technomyrmex difficilis, both forming part of a species complex with a worldwide distribution.

<i>Vespula pensylvanica</i> Species of wasp

Vespula pensylvanica, the western yellowjacket, is a Nearctic species of wasp in the genus Vespula. It is native to regions of North America, largely in areas with northern temperate climates. Its reproductive behavior is constrained by cold weather, which successfully reduces the number of western yellowjackets in cold months. However, in the absence of cold weather, this wasp's population can explode. The western yellowjacket has become particularly invasive in the Hawaiian Islands, resulting in their label as a major pest.

Green-head ant Species of ant

The green-head ant, also known as the green ant or metallic pony ant, is a species of ant that is endemic to Australia. It was described by British entomologist Frederick Smith in 1858 as a member of the genus Rhytidoponera in the subfamily Ectatomminae. These ants measure between 5 to 7 mm. The queens and workers look similar, differing only in size, with the males being the smallest. They are well known for their distinctive metallic appearance, which varies from green to purple or even reddish-violet. Among the most widespread of all insects in Australia, green-head ants are found in almost every Australian state, but are absent in Tasmania. They have also been introduced in New Zealand, where several populations have been established.

<i>Pheidole megacephala</i> Species of ant

Pheidole megacephala is a species of ant in the family Formicidae. It is commonly known as the big-headed ant in the USA and the coastal brown ant in Australia. It is a very successful invasive species and is considered a danger to native ants in Australia and other places. It is regarded as one of the world's worst invasive ant species.

<i>Oecophylla longinoda</i> Species of ant

Oecophylla longinoda is a species of arboreal ant found in the forested regions of tropical Africa. They are one of only two extant species of the genus Oecophylla, the other being O. smaragdina. They make nests in trees made of leaves stitched together using the silk produced by their larvae.

<i>Crematogaster carinata</i> Species of ant

Crematogaster carinata is a species of ant in the tribe Crematogastrini. It was first described by Gustav Mayr in 1862. It is native to Central and South America, where it is a common species, forming large colonies in the canopy of the forest.

<i>Camponotus herculeanus</i> Species of ant known as the Hercules ant

Camponotus herculeanus is a species of ant in the genus Camponotus, the carpenter ants, occurring in Northern Eurasia, from Norway to Eastern Siberia, and North America. First described as Formica herculeana by Linnaeus in 1758, the species was moved to Camponotus by Mayr in 1861.

<i>Novomessor ensifer</i> Species of ant

Novomessor ensifer is a species of ant endemic to Mexico. A member of the genus Novomessor in the subfamily Myrmicinae, it was first described by Swiss entomologist Auguste Forel in 1899. N. ensifer was originally a part of the genus Aphaenogaster until a recent phylogenetic study concluded that Novomessor was genetically distinct and should be separated. The ant is a medium-sized species, measuring 5.5 to 10 millimetres. The ant is ferruginous-colored in some certain parts of the body, and small workers (nanitics) in incipient colonies are noticeably different in color and body structure.


  1. 1 2 Dlussky, Gennady M.; Torsten Wappler; Sonja Wedmann (2008). "New middle Eocene formicid species from Germany and the evolution of weaver ants" (PDF). Acta Palaeontologica Polonica. 53 (4): 615–626. doi: 10.4202/app.2008.0406 .
  2. 1 2 "Weaver Ant – Oecophylla smaragdina. Facts, Identification". antARK. Retrieved 12 January 2017.
  3. 1 2 3 "Green Tree Ants — State of the Environment Report" . Retrieved 7 January 2017.
  4. 1 2 3 4 5 6 Kusters, Koen; Belcher, Brian (2004). Forest Products, Livelihoods and Conservation: case studies of non-timber forest product systems. Volume 1 – Asia. CIFOR. pp. 61–69. ISBN   978-979-3361-23-9.
  5. 1 2 3 Blüthgen, Nico; Fiedler, Konrad (2002). "Interactions between weaver ants Oecophylla smaragdina, homopterans, trees and lianas in an Australian rain forest canopy". Journal of Animal Ecology. 71 (5): 793–801. doi: 10.1046/j.1365-2656.2002.00647.x .
  6. Majno, Guido (1991). The Healing Hand: Man and Wound in the Ancient World . Harvard University Press. p.  307. ISBN   978-0-674-38331-9.
  7. Babu, Martin J.; Patil, Rajashekhar K. (1 December 2021). "Antennal lobe organisation in ant, Oecophylla smaragdina: A Golgi study". Journal of Biosciences. 46 (4): 110. doi:10.1007/s12038-021-00233-8. ISSN   0973-7138.
  8. "Oecophylla smaragdina (Fabricius, 1775)". The DNA of Singapore. Lee Kong Chian Natural History Museum. Retrieved 6 January 2017.
  9. Braby, Michael F. (2004). The Complete Field Guide to Butterflies of Australia. CSIRO Publishing. p.  232. ISBN   978-0-643-09968-5.
  10. Césard N. (2004). "Le kroto (Oecophylla smaragdina) dans la région de Malingping, Java-Ouest, Indonésie : collecte et commercialisation d'une ressource animale non négligeable" (PDF). Anthropozoologica (in French). 39 (2): 15–31.
  11. Sribandit, Wissanurak; et al. (2008). "The importance of weaver ant (Oecophylla smaragdina Fabricius) harvest to a local community in Northeastern Thailand" (PDF). Asian Myrmecology. 2: 129–138.
  12. Devasahayam, S.; Anita Devasahayam (2019) Controlling insect pests in cowpea with weaver ants. Accessed from: https://besgroup.org/2019/06/27/controlling-insect-pests-in-cowpea-with-weaver-ants/.
  13. 1 2 Fisher, T.W.; Bellows, Thomas S.; Caltagirone, L.E.; Dahlsten, D.L.; Huffaker, Carl B.; Gordh, G. (1999). Handbook of Biological Control: Principles and Applications of Biological Control. Academic Press. p. 458. ISBN   978-0-08-053301-8.