''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 Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. The habitats pose nu ...

ant 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 ...

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

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. ...

e: hence the name 'oecophylla' reek for 'leaf-house'

Description

Workers and major workers are mostly coloured orange. Workers are long; they look after larvae and farm scale bugs for honeydew. Major workers are long, with long strong legs and large mandibles. They forage, assemble and expand the nest. Queens are typically long, and normally greenish-brown, giving the species its name ''smaragdina'' (

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

: emerald).

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 The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an Australian territory in the central and central northern regions of Australia. The Northern Territory shares its borders with Western Aust ...

and

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

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. 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. 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. The average life of a mature colony may be eight years.

Ecology

Weaver ants of this species are important parts of the

ecosystem An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syste ...

in tree canopies in humid tropical regions. 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. Weaver ants feed on insects and other invertebrates, their prey being mainly beetles, flies and hymenopterans. 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 ''Glomerulus'' () is a common term used in anatomy to describe globular structures of entwined vessels, fibers, or neurons. ''Glomerulus'' is the diminutive of the Latin ''glomus'', meaning "ball of yarn". ''Glomerulus'' may refer to: * the filter ...

is seen in clusters, this appears to be a common feature in many Hymenopterans such as ants and honeybees. In Singapore, colonies are often found in sea hibiscus and

great morinda ''Morinda citrifolia'' is a fruit-bearing tree in the coffee family, Rubiaceae. Its native range extends across Southeast Asia and Australasia, and was spread across the Pacific by Polynesian sailors. The species is now cultivated throughout th ...

trees which entice the ants with nectar, the trees in return receiving protection from herbivorous insects. In Indonesia, the trees supporting colonies include banana, coconut,

oil palm ''Elaeis'' () is a genus of palms containing two species, called oil palms. They are used in commercial agriculture in the production of palm oil. The African oil palm '' Elaeis guineensis'' (the species name ''guineensis'' referring to its c ...

rubber tree ''Hevea brasiliensis'', the Pará rubber tree, ''sharinga'' tree, seringueira, or most commonly, rubber tree or rubber plant, is a flowering plant belonging to the spurge family Euphorbiaceae originally native to the Amazon basin, but is now ...

, cacao,

teak Teak (''Tectona grandis'') is a tropical hardwood tree species in the family Lamiaceae. It is a large, deciduous tree that occurs in mixed hardwood forests. ''Tectona grandis'' has small, fragrant white flowers arranged in dense clusters ( pan ...

jackfruit The jackfruit (''Artocarpus heterophyllus''), also known as jack tree, is a species of tree in the fig, mulberry, and breadfruit family ( Moraceae). Its origin is in the region between the Western Ghats of southern India, all of Bangladesh, ...

, mango, Chinese laurel, petai, jengkol,

duku ''Lansium parasiticum'', commonly known as langsat (), lanzones (), or longkong in English; duku in Indonesian or dokong in Terengganu Malay, is a species of tree in the Mahogany family with commercially cultivated edible fruits. The speci ...

rambutan Rambutan (; taxonomic name: ''Nephelium lappaceum'') is a medium-sized tropical tree in the family Sapindaceae. The name also refers to the edible fruit produced by this tree. The rambutan is native to Southeast Asia. It is closely related to s ...

jambu air ''Syzygium samarangense'' is a species of flowering plant in the family Myrtaceae, native to an area that includes the Greater Sunda Islands, Malay Peninsula, and the Andaman and Nicobar Islands, but introduced in prehistoric times to a wider ...

and kedondong. The ants also attend

aphid Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...

s, scale insects and other

homoptera Homoptera is a suborder of order Hemiptera that is considered by some taxonomists to be paraphyletic, and therefore deprecated (obsolete). It was therefore split into the suborders Sternorrhyncha, Auchenorrhyncha, and Coleorrhyncha. The earlier w ...

ns 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. 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. Shelters may be built by the ants close to their nests specially to protect these assets. 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 Aggressive mimicry is a form of mimicry in which predators, parasites, or parasitoids share similar signals, using a harmless model, allowing them to avoid being correctly identified by their prey or host. Zoologists have repeatedly compare ...

. 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. The jumping spider '' Myrmaplata plataleoides'' is a

batesian mimic Batesian mimicry is a form of mimicry where a harmless species has evolved to imitate the warning signals of a harmful species directed at a predator of them both. It is named after the English naturalist Henry Walter Bates, after his work on bu ...

of this species''.'' This spider visually mimics this ant, via contracted body parts to create the illusion of a

hymenopteran 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 typica ...

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.

Uses

The larvae and pupae are collected and processed into

bird food Bird food or bird seed is food (often varieties of seeds, nuts, and/or dried fruits) intended for consumption by wild and domestic birds. While most bird food is fed to commercial fowl (such as chicken or turkey), bird food is also used to fe ...

and fish bait in Indonesia, are used in Chinese and Indian traditional medicine, and consumed as a delicacy in Thailand and other countries. In Java, Indonesia the larvae and pupae of these ants are known as ''kroto'' and are harvested commercially for use as captive

songbird A songbird is a bird belonging to the suborder Passeri of the perching birds (Passeriformes). Another name that is sometimes seen as the scientific or vernacular name is Oscines, from Latin ''oscen'', "songbird". The Passeriformes contains 5000 ...

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. 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 An aphrodisiac is a substance that increases sexual desire, sexual attraction, sexual pleasure, or sexual behavior. Substances range from a variety of plants, spices, foods, and synthetic chemicals. Natural aphrodisiacs like cannabis or cocai ...

. 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. In some parts of this ant's range, colonies are used as a natural form of

pest control Pest control is the regulation or management of a species defined as a pest; any animal, plant or fungus that impacts adversely on human activities or environment. The human response depends on the importance of the damage done and will range ...

. Crops that have been protected in this way have included cowpea,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/. cashew,

citrus ''Citrus'' is a genus of flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including important crops such as oranges, lemons, grapefruits, pomelos, and limes. The genus ''Citrus'' is native to ...

, mango, coconut, cocoa and

coffee Coffee is a drink prepared from roasted coffee beans. Darkly colored, bitter, and slightly acidic, coffee has a stimulant, stimulating effect on humans, primarily due to its caffeine content. It is the most popular hot drink in the world. S ...

. 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. 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".

Gallery

File:Oecophylla smaragdina MHNT reine.jpg, A queen that has shed its wings File:Oecophylla smaragdina-.jpg, Weaver ant queen, prior to shedding wings File:Weaverantnest05268.jpg, Weaver ant nest on a mango tree File:Weaver ants (Oecophylla smaragdina) nest in Kinnarsani WS, AP W IMG 6012.jpg, Nest in

Kinnerasani Wildlife Sanctuary Kinnerasani Wildlife Sanctuary is a forest located in Bhadradri Kothagudem district, Telangana state of India. The wildlife sanctuary is spread over an area of with the picturesque Kinnerasani Lake with densely forested islands in the middle ...

, India File:Red weaver ants (Oecophylla smaragdina) feeding on a dead African giant snail (Achatina fulica) - journal.pone.0060797.g001-F.png, Weaver ants feeding on a dead

African giant snail African or Africans may refer to: * Anything from or pertaining to the continent of Africa: ** People who are native to Africa, descendants of natives of Africa, or individuals who trace their ancestry to indigenous inhabitants of Africa *** Ethn ...

File:Two weaver ants.JPG, Two ants transferring a larva File:Red weaver ants transporting a dead gecko, in Laos.jpg, Worker ants transporting a dead gecko File:Red weaver ants transporting a dead gecko, in Laos (video).webm, Worker ants transporting a dead gecko

References

External links

* {{Taxonbar, from=Q1132830 Formicinae Hymenoptera of Asia Hymenoptera of Australia Insects of India Nepenthes infauna Insects described in 1775 Taxa named by Johan Christian Fabricius