Dorylus
Encyclopedia
The army ant
genus Dorylus, also known as driver ants, safari ants, or siafu, is found primarily in central and east Africa
, although the range also extends to tropical Asia
. The term siafu is a loanword
from Swahili
, and is one of numerous similar words from regional Bantu languages
used by indigenous peoples
to describe various species of these ants. Unlike the New World
members of the subfamily Ecitoninae
, members of this genus do form temporary anthills lasting from a few days up to three months. Each colony
can contain over 20 million individuals. As with their New World counterparts, there is a soldier
class among the workers, which is larger, with a very large head and pincer-like mandibles. They are capable of stinging, but very rarely do so, relying instead on their powerful shearing jaws.
Seasonally, when food
supplies become short, they leave the hill and form marching columns of up to 50,000,000 ants which are considered a menace to people, though they can be easily avoided; a column can only travel about 20 metres in an hour. It is for those unable to move, or when the columns pass through homes, that there is the greatest risk. There have been reported cases of people— usually the young, infirm, or otherwise debilitated— being killed and eventually consumed by them, often dying of asphyxiation as the ants crowd into the esophagus and block the passage of air. Their presence is, conversely, beneficial to certain human communities, such as the Maasai, as they perform a pest prevention service in farming communities, consuming the majority of other crop-pests, from insects to large rats.
The characteristic long columns of ants will fiercely defend against anything that encounters them. Columns are arranged with the smaller ants being flanked by the larger soldier ants. These automatically take up positions as sentries, and set a perimeter corridor in which the smaller ants can run safely. Their bite is severely painful, each soldier leaving two puncture wounds when removed. Removal is difficult, however, as their jaws are extremely strong, and one can pull a soldier ant in two without it releasing its hold. Large numbers of ants can kill small or immobilized animals and eat the flesh. A large part of their diet is earthworms. All Dorylus species are blind, though they, like most varieties of ants, communicate primarily through pheromone
s.
In mating season alate
s (winged queens and drones) are formed. The drones are larger than the soldiers and the queens are much larger. They mate on the wing, and the queens go off to establish new colonies. As with most ant
s, workers and soldiers are sterile (non-reproducing) females.
Male driver ants, sometimes known as "sausage flies" (a term also applied to males of New World ecitonines) due to their bloated, sausage-like abdomen
s, are the largest known ants, and were originally believed to be members of a different species. Males leave the colony soon after hatching, but are drawn to the scent trail left by a column of siafu once it reaches sexual maturity. When a colony of driver ants encounters a male, they tear its wings off and carry it back to the nest to be mated with a virgin queen. As with all ants, the males die shortly afterward.
Such is the strength of the ant's jaws that in East Africa they are used as natural, emergency sutures. Various East African indigenous tribal peoples (e.g. Maasai moran), when suffering from a gash in the bush, will use the soldiers to stitch the wound by getting the ants to bite on both sides of the gash, then breaking off the body. This use of ants as makeshift surgical staple
s creates a seal that can hold for days at a time, and the procedure can be repeated if necessary, allowing natural healing to commence.
Several species in this genus carry out raids on termitaria, paralysing or killing some of the termites and carting them back to the nest.
Army ant
The name army ant is applied to over 200 ant species, in different lineages, due to their aggressive predatory foraging groups, known as "raids", in which huge numbers of ants forage simultaneously over a certain area, attacking prey en masse.Another shared feature is that, unlike most ant...
genus Dorylus, also known as driver ants, safari ants, or siafu, is found primarily in central and east Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, although the range also extends to tropical Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
. The term siafu is a loanword
Loanword
A loanword is a word borrowed from a donor language and incorporated into a recipient language. By contrast, a calque or loan translation is a related concept where the meaning or idiom is borrowed rather than the lexical item itself. The word loanword is itself a calque of the German Lehnwort,...
from Swahili
Swahili language
Swahili or Kiswahili is a Bantu language spoken by various ethnic groups that inhabit several large stretches of the Mozambique Channel coastline from northern Kenya to northern Mozambique, including the Comoro Islands. It is also spoken by ethnic minority groups in Somalia...
, and is one of numerous similar words from regional Bantu languages
Bantu languages
The Bantu languages constitute a traditional sub-branch of the Niger–Congo languages. There are about 250 Bantu languages by the criterion of mutual intelligibility, though the distinction between language and dialect is often unclear, and Ethnologue counts 535 languages...
used by indigenous peoples
Indigenous peoples
Indigenous peoples are ethnic groups that are defined as indigenous according to one of the various definitions of the term, there is no universally accepted definition but most of which carry connotations of being the "original inhabitants" of a territory....
to describe various species of these ants. Unlike the New World
New World
The New World is one of the names used for the Western Hemisphere, specifically America and sometimes Oceania . The term originated in the late 15th century, when America had been recently discovered by European explorers, expanding the geographical horizon of the people of the European middle...
members of the subfamily Ecitoninae
Ecitoninae
Most New World army ants belong to the subfamily Ecitoninae. This subfamily is further broken into two groups in the New World, the tribes Cheliomyrmecini and Ecitonini. The former contains only the genus Cheliomyrmex, and the tribe Ecitonini contains four genera, Neivamyrmex, Nomamyrmex, Labidus,...
, members of this genus do form temporary anthills lasting from a few days up to three months. Each colony
Colony
In politics and history, a colony is a territory under the immediate political control of a state. For colonies in antiquity, city-states would often found their own colonies. Some colonies were historically countries, while others were territories without definite statehood from their inception....
can contain over 20 million individuals. As with their New World counterparts, there is a soldier
Soldier
A soldier is a member of the land component of national armed forces; whereas a soldier hired for service in a foreign army would be termed a mercenary...
class among the workers, which is larger, with a very large head and pincer-like mandibles. They are capable of stinging, but very rarely do so, relying instead on their powerful shearing jaws.
Life cycle
Food
Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals...
supplies become short, they leave the hill and form marching columns of up to 50,000,000 ants which are considered a menace to people, though they can be easily avoided; a column can only travel about 20 metres in an hour. It is for those unable to move, or when the columns pass through homes, that there is the greatest risk. There have been reported cases of people— usually the young, infirm, or otherwise debilitated— being killed and eventually consumed by them, often dying of asphyxiation as the ants crowd into the esophagus and block the passage of air. Their presence is, conversely, beneficial to certain human communities, such as the Maasai, as they perform a pest prevention service in farming communities, consuming the majority of other crop-pests, from insects to large rats.
The characteristic long columns of ants will fiercely defend against anything that encounters them. Columns are arranged with the smaller ants being flanked by the larger soldier ants. These automatically take up positions as sentries, and set a perimeter corridor in which the smaller ants can run safely. Their bite is severely painful, each soldier leaving two puncture wounds when removed. Removal is difficult, however, as their jaws are extremely strong, and one can pull a soldier ant in two without it releasing its hold. Large numbers of ants can kill small or immobilized animals and eat the flesh. A large part of their diet is earthworms. All Dorylus species are blind, though they, like most varieties of ants, communicate primarily through pheromone
Pheromone
A pheromone is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting outside the body of the secreting individual to impact the behavior of the receiving individual...
s.
In mating season alate
Alate
An alate is a winged reproductive of a social insect . Alate females are typically those destined to become queens , whereas alate males are occasionally referred to as "drones"...
s (winged queens and drones) are formed. The drones are larger than the soldiers and the queens are much larger. They mate on the wing, and the queens go off to establish new colonies. As with most ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
s, workers and soldiers are sterile (non-reproducing) females.
Male driver ants, sometimes known as "sausage flies" (a term also applied to males of New World ecitonines) due to their bloated, sausage-like abdomen
Abdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
s, are the largest known ants, and were originally believed to be members of a different species. Males leave the colony soon after hatching, but are drawn to the scent trail left by a column of siafu once it reaches sexual maturity. When a colony of driver ants encounters a male, they tear its wings off and carry it back to the nest to be mated with a virgin queen. As with all ants, the males die shortly afterward.
Such is the strength of the ant's jaws that in East Africa they are used as natural, emergency sutures. Various East African indigenous tribal peoples (e.g. Maasai moran), when suffering from a gash in the bush, will use the soldiers to stitch the wound by getting the ants to bite on both sides of the gash, then breaking off the body. This use of ants as makeshift surgical staple
Surgical staple
Surgical staples are specialized staples used in surgery in place of sutures to close skin wounds, connect or remove parts of the bowels or lungs. A more recent development, from the 1990s, uses clips instead of staples for some applications; this does not require the staple to penetrate.Stapling...
s creates a seal that can hold for days at a time, and the procedure can be repeated if necessary, allowing natural healing to commence.
Several species in this genus carry out raids on termitaria, paralysing or killing some of the termites and carting them back to the nest.
Species
- D. acutus SantschiFelix SantschiFelix Santschi was a Swiss entomologist.Santschi is known for his pioneering work on the navigational abilities of ants. In one experiment, he investigated the way harvester ants used the sky to navigate. He found that as long as even a small patch of sky was visible, the ants could return...
, 1937 - D. aethiopicus EmeryCarlo EmeryCarlo Emery was an Italian entomologist.Born in Naples, Carlo Emery was professor of Zoology at the University of Bologna. He later worked in Geneva...
, 1895 - D. affinis Shuckard, 1840
- D. agressor Santschi, 1923
- D. alluaudi Santschi, 1914
- D. atratus Smith, 1859
- D. atriceps Shuckard, 1840
- D. attenuatus Shuckard, 1840
- D. bequaerti Forel, 1913
- D. bishyiganus (Boven, 1972)
- D. braunsi Emery, 1895
- D. brevipennis Emery, 1895
- D. brevis Santschi, 1919
- D. buyssoni Santschi, 1910
- D. congolensis Santschi, 1910
- D. conradti Emery, 1895
- D. depilis Emery, 1895
- D. diadema Gerstaecker, 1859
- D. distinctus Santschi, 1910
- D. ductor Santschi, 1939
- D. emeryi Mayr, 1896
- D. erraticus (Smith, 1865)
- D. faurei Arnold, 1946
- D. fimbriatus (Shuckard, 1840)
- D. fulvus (Westwood, 1839)
- D. funereus Emery, 1895
- D. furcatus (Gerstaecker, 1872)
- D. fuscipennis (Emery, 1892)
- D. gaudens Santschi, 1919
- D. ghanensis Boven, 1975
- D. gribodoi Emery, 1892 – includes D. gerstaeckeri Emery, 1895
- D. helvolus (Linnaeus, 1764)
- D. katanensis Stitz, 1911
- D. kohli Wasmann, 1904
- D. labiatus Shuckard, 1840
- D. laevigatusDorylus laevigatusDorylus laevigatus is a member of the army ant genus Dorylus, or Old World army ants. More specifically known as "driver ants", the genus Dorylus is abundant throughout Africa and stretches into tropical Asia, where D. laevigatus is primarily found. They are a eusocial colony-forming species, which...
(Smith, 1857) - D. lamottei Bernard, 1953
- D. leo Santschi, 1919
- D. mandibularis Mayr, 1896
- D. mayri Santschi, 1912
- D. moestus Emery, 1895
- D. molestusDorylus molestusDorylus molestus is a species of African army ant.-Taxonomy:Other names:Anomma molestus,Dorylus molestus,Dorylus nigricans molestus,Dorylus molestus ,Dorylus nigricans molestus....
Wheeler, 1922 - D. montanus Santschi, 1910
- D. niarembensis (Boven, 1972)
- D. nigricans IlligerJohann Karl Wilhelm IlligerJohann Karl Wilhelm Illiger was a German entomologist and zoologist.Illiger was the son of a merchant in Brunswick. He studied under the entomologist Johann Hellwig, and later worked on the zoological collections of Johann Centurius Hoffmannsegg...
, 1802 - D. ocellatus (Stitz, 1910)
- D. orientalis Westwood, 1835
- D. politus Emery, 1901
- D. rufescens Santschi, 1915
- D. savagei Emery, 1895
- D. schoutedeni Santschi, 1923
- D. spininodis Emery, 1901
- D. stadelmanni Emery, 1895
- D. stanleyi Forel, 1909
- D. staudingeri Emery, 1895
- D. striatidens Santschi, 1910
- D. termitarius Wasmann, 1911
- D. titan Santschi, 1923
- D. vishnui Wheeler, 1913
- D. westwoodii (Shuckard, 1840)
- D. wilverthi Emery, 1899
- Rebel Hafner