''Myrmelachista schumanni'', also known as the lemon ant, is a species of

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 22 ...

from

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

. It is notable for the creation of

Devil's garden In myrmecology and forest ecology, a devil's garden (Kichwa: ''Supay chakra''Frederickson, M. E., & Gordon, D. (2007). The devil to pay: the cost of mutualism with ''Myrmelachista schumanni'' ants in 'devil's gardens' is increased herbivory on ' ...

. Using its own

herbicide Herbicides (, ), also commonly known as weedkillers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page fo ...

they kill off all the plants in an area except for the

myrmecophytes Myrmecophytes (; literally "ant-plant") are plants that live in a mutualistic association with a colony of ants. There are over 100 different genera of myrmecophytes. These plants possess structural adaptations that provide ants with food and/o ...

, or ant-plants, in which they reside.

Ant–plant mutualism

''M. schumanni'' live in large clearings in the rainforest, called

devil's garden In myrmecology and forest ecology, a devil's garden (Kichwa: ''Supay chakra''Frederickson, M. E., & Gordon, D. (2007). The devil to pay: the cost of mutualism with ''Myrmelachista schumanni'' ants in 'devil's gardens' is increased herbivory on ' ...

s, where there is little to no bio-diversity compared to the surrounding area. There are only one to three species of plants found in these areas consisting of ''Cordia nodosa'', ''Tococa guianensis'', ''

Duroia hirsuta ''Duroia hirsuta'' is a myrmecophyte tree species from the Amazon Forest. It is one of some 37 species of ''Duroia,'' which are shrubs or canopy trees in the family Rubiaceae, favouring ants (myrmecophilous), and occurring in Central America as f ...

'' or ''Clidemia heterophylla''. The few studies of the mutualism between ''M. schumanni''–''D. hirsuta'' have incorrectly concluded that these clearings are formed by

allelopathy Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have be ...

on the part of ''D. hirsuta''. It was later established that

worker 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 22,00 ...

s were injecting leaves with

formic acid Formic acid (), systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula HCOOH and structure . It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Es ...

, a toxin commonly produced in ant species, and the plants started to die within 24 hours. Lemon ants are the only known insect to use formic acid as a herbicide. By killing other plants, the lemon ants provide themselves with a nest site, usually residing in D. ''hirsuta''. Researchers estimate that the largest garden observed, contains 328 trees over 1,300 square meters and is around 800 years old.

Name

Lemon ants get their name from the lemony taste of acids produced as part of a glandular chemical defense system. When crushed or attacked, citronellal pheromones are created to communicate alarm to nearby individuals, which also produces a citrus odor.

References

Formicinae Hymenoptera of South America Insects described in 1890 Taxa named by Carlo Emery {{formicinae-stub