Eciton burchellii

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Eciton burchellii

Soldier with characteristically shaped mandibles.

Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Ecitoninae
Tribe:	Ecitonini
Genus:	Eciton
Species:	E. burchellii

Binomial name

Eciton burchellii
Westwood, 1842

Subspecies^[1]

Eciton burchellii burchellii
Eciton burchellii cupiens
Eciton burchellii foreli
Eciton burchellii parvispinum
Eciton burchellii urichi

Eciton burchellii is the predominant species of the genus Eciton and a type of New World army ant. Distinct in its expansive, highly organized swarm raids, it is often considered the archetypal species of the term "army ant", which has become its common name, and one of the most heavily investigated of all ant species.

As with most ants, they are polymorphic, meaning that individuals vary in size; a colony contains workers ranging from 3mm to 12mm, with each specific "caste" being suited to specialized tasks. As with other species of Eciton, E. burchellii features a highly modified soldier caste bearing long, pointed, characteristically falcate (sickle-shaped) mandibles. Their long legs and elongated body lend a spider-like appearance. Color varies from deep golden to dark brown. Workers possess single faceted compound eyes, double segmented waists, a well developed sting, and specialized tarsal hooks on their feet with which they cling to one another to form bridges and bivouacs.

Colonies may be quite large, accommodating as many as 100,000 to 2,000,000 adult individuals. Each colony consists of a single queen, a brood of developing young, and a majority of adult workers.

The species has been observed using their bodies to block potholes in a path between the nest and prey. The ants will each walk to a hole and measure themselves to see if they are a fit for it and if they are, will lie across the hole to allow other members of the colony to cross at higher speed. If they do not fit, they will continue past the hole and allow another ant to check. Once in place in a hole the ant can stay there for many hours, until it is dark and the traffic flow has diminished greatly, at which point they will return to the nest. ^[2]

The species is the swarming ant most commonly attended by "ant following" birds such as antbirds and woodcreepers.^[3] Insects and other arthropods attempting to escape from E. burchellii are flushed into the attending flocks, and a number of species have evolved to obtain most of their food by following swarms.

[edit] Naming

The species was referred to as Eciton burchellii in the original publication. The double i was subsequently deemed unnecessary in the later 1800s by taxonomists, and hence the name became Eciton burchelli. However, taxonomic rules have recently been stricter in adhering to the original form^[4]; the name Eciton burchelli is now largely regarded as invalid.^[5]