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Atta cephalotes has subterranean refuse dumps where spent fungus substrate is deposited. This is in contrast to A. colombica, which has conspicuous refuse dumps on the surface.
Nuptial flights occur during predawn hours and are synchronized across colonies in a population. Massive emergences occur sporadically during the year. On mornings following nuptial flights trails and clearings are sprinkled with the large queens and males, most of them being eaten by ants and other predators.
Southernmost Mexico to Ecuador and Brazil, and from the Lesser Antilles as far north as Bardbados. An apparently disjunct population occurs in the Atlantic Coastal Forests of Brazil.Occasionally intercepted at US Ports of Entry.
Atta cephalotes vs. Atta sexdensAtta cephalotes can be distinguished by the wooly hairs on the heads of major workers and the shinier integument caused by the lack of hexagonal microsculpture, and the lack of small teeth or dents on the head anterior to the posterolateral spines. The pronotal spines of A. cephalotes tend to be more curved than those of its congeners, but this is a highly variable character.Atta cephalotes vs. Atta native to the United StatesThe majors of A. cephalotes are also distinguished from its two congeners native to the United States (A. mexicana and A. texana) by the presence of wooly hairs on the cephalic dorsum. The petiolar spiracles are visible from above in the two native species, but cannot be seen from above in A. cephalotes (Borgmeier, 1959).
Atta cephalotes vs. AcromyrmexAtta cephalotes is distinguished from its close relatives in the genus Acromyrmex by the presence of only three long spines on the mesosomal dorsum, and the absence of tubercles on the mesosomal and gastric dorsum.
Diagnosis among introduced and commonly intercepted speciesAntenna 11-segmented. Antennal club indistinct. Antennal insertions at least partly covered by frontal lobes. Antennal scrobe lacking. Antennal scapes not conspicuously short; easily extended beyond eye level. Posterolateral corners of head spinose; lacking pair of small teeth anterior to posterolateral spines. Head smooth and shiny, not covered by hexagonal microsculpture. Head of soldier appearing wooly, covered in abundant long fine overlapping hairs. Mandibles triangular. Waist 2-segmented. Petiole with a distinct and upright node. Postpetiole attached to lower surface of gaster. Dorsum of promesonotum with 2 pairs of spines or teeth. Propodeum armed with spines. First gastral tergite lacking numerous tubercles. Yellow to reddish brown.
Redescription translated from Borgmeier, 1959b: 340 The most complete description of the soldiers of this important kind of gave De Geer (1773). On the reproductives did Mayr (1865) and Emery (1890, 1913), important information, and the drawings of male genitalia in Emery (1913 8) are absolutely accurate. Among the new authors are concerned Goncalves (1942) and Borg Meier (1950) with the taxonomy of this kind is an actual description of all searches in the box recent literature in vain.
Type locality: Paramaribo, Suriname.
Workers. - Maxima (Paramaribo): 14 mm length with his head bowed. Head width 6, 1 mm. Occiput gently bulged in the middle. Occipital zaehne short, often reduced to tubercles. Occipital lobes thickened and rounded, the front on each side with long hair of woolly Bueschel. Forehead with 3 ocelli, the posterior small, sometimes absent. Eyes strongly convex. Thorax narrower than the head of many (width front 2.7 mm). Pronotum on each side at the lower edge with a curved spine. Mesonotum with 2 pairs of spines, the anterior with a broad base, often rounded up and the back short and sharp. Epinotaldornen straight, directed backwards and upwards. Petiole and postpetiole side recently with one tooth. Gaster: width 3.5 mm. Legs slender; hind tibiae 5 mm. Shiny little head forward. Occiput polished, naked, matt body. Face, thorax, pedicel and gaster with long woolly hair, sparse hair, protruding, hairy legs sticking out. Rusty brown color. - Media (Paramaribo): length 7 mm. Head width 2, 6 mm. Occiput bulged wide. Kapfflach in profile. Occipital spines slightly shorter than the eye. Front Mesonotal spines thin and long, curved forward, the back short and pointed. Epinotal spines too thin, slightly shorter than the mesonotal spines. Forehead with shiny ribbon on the center. Thorax shiny little. Gaster dull. Kapf, thorax and gaster with long hair and short protruding fitting Pubescenz. - Minima (Paramaribo) L. about 2 mm. Head without mandibles as long as breil Occipital spines very short or obsolete. Mesonotal thorns short, often missing the rear. Epinotal spines longer. Color yellow. Tegument something shiny. Prominent scattered hairs.
Females (Paramaribo). - Length 22 mm. Head width 5, 25ri1m. Occipital edge almost straight. Lies behind corners without head gear, at most with weak tubercles. Sides of the head behind the eyes convex, strongly convergent forward. Ocelli large. Eyes convex. Mandibles glossy, striped, teeth with blunt Apikalzahn and 8-9. Epinotum reinforced. Thorax length 10 mm. Gaster Br 8.5 mm. Tibia III 5.4 mm. Wing about 28 mm at the outer edge strongly browned. Matt. Head, thorax and gaster with fine golden pubescence fitting. Legs fitting coat or diagonally. Yellow rust stain.
Males (Paramaribo). - Length about 18 mm. Head (Borgm. 1950, Figure 47): width 2, 8 mm. Occipital zaehne obsolete. Front plate with teeth. Eyes strongly convex. Mandibles narrow, inner margin concave, irregularly toothed, pointed Apikalzahn. Scape too thin, 2, 6 mm, on the apical half slightly thickened. Wing about 25 mm, outer margin strongly browned. Genitalia (Fig. 10): Not Squamula dorsally fused in the middle, longer than wide; stipes articulated to the Squamula, not fused with it, abgestuzt apical hair long. Voisellen stabfoermig, in profile gently curved, apically obliquely truncated. Sagittae built complex, each side with an upright sharpened keel, which extends to the base, where it terminates in a spike, the keels slightly diverging apically, basally more strongly, laterally outside of it there is a curved hook. is occupied at its end and the back edge with tiny sharp teeth, on the ventral side of the Sagitta's in the middle line, two closely spaced keels, which are in profile convex and serrated saw-are (the teeth are kopfwaerts directed and curved), which two keels separated by a furrow that widens and forms the apical foramen, located above the foramen on each side a broad, flat, triangular teeth. Subgenital bulged apically. Head and thorax woolly, 1st Gaster short segment pubescent. Color yellow rust or rust-brown.
Geographical distribution. - Mexico (Veracruz), Central America, Ecuador, Columbia, Peru, Bolivia (Chapare up), Venezuela, Guyana, Brazil (Amazonas, Para, Rondonia, Maranhao, Pernambuco, Baia (up I1heus, Belmonte and Mucuri).
Discussion. - Atta colombica cephalotes is very close, as evidenced by the male genitalia and the form det average worker, but colombica differs in the following important points: 1) the head of the soldiers is totally different, much narrower, incised on occipital deep edge, 2) the soldier is practically naked, pubescent only very fine fitting, and 3) in the middle are the workers Occipital spines always longer than the eye (at shorter cephalotes), 4) the male genitalia is squamate the top as long as wide, 5) are the Sagittalhaken less curved and serrated edge on the back clearly. The females of both species are hardly distinguishable (by colombica are slightly smaller). The dark brown female from Colombia, Bolivia and Costa Rica can easily be confused sexdens, etc., but are identified by the absence of Occipital zaehne and the darkened edge of the wing.
Variation. - Apart from the strong polymorphism workers vary enormously in shape and painting, sculpture and pubescence. Copies of Columbia, Bolivia, Peru and Costa Rica are dark brown and the soldiers have dull occipital (var opaca), while the females are covered with hair sticking out. Little Workers of Trinidad (3-4 mm) are bright yellow and very shiny all over her body (formerly referred to by me as lutea). The shape of the stipes varies (cf Borgm. In 1950, FIG 39, 43-46), also the head of conspecific males (ibid. Fig 47-51). The shape of the Sagitta is relatively constant (Fig. ibid. 35-37).
Synonymy. - The large variability of cephaloles it is not surprising that a number of synonyms exist in the literature. In the old synonyms that are far from clear, I do not discuss (d Emery, 1923).
Atta cephalotes is the most widely distributed species of leaf cutting ant. It occurs from southernmost Mexico to Ecuador and Brazil, and from the Lesser Antilles as far north as Bardbados (Holldobler & Wilson, 1990). An apparently disjunct population occurs in the Atlantic Coastal Forests of Brazil (Solomon, 2007). The species is widely regarded as a significant pest on crops including citrus, coffee, cocoa and ornamentals (Cherrett, 1986; Cherrett & Peregrine, 1976). The ecological success and ubiquity of A. cephalotes is owed in large part to its broad niche tolerance with respect to both nesting habitats and diet breadth (Solomon, 2007). The species has evolved to specialize in forest gaps, and consequently thrives in disturbed habitats such as farms and plantations (Cherrett & Peregrine, 1976). Niche modeling suggests that the current range of A. cephalotes is limited by dispersal constraints rather than suitable habitat (Solomon, 2007), and could cause significant ecological and agricultural devastation should it become introduced elsewhere (Hlldobler & Wilson, 1990). Atta cephalotes is highly variable, both among castes of the same colony and across populations. Workers vary enormously in shape, color, sculpture and pubescence (Borgmeier, 1959).
Extant: 1 valid subspecies
Formica cephalotes Linnaeus, 1758 PDF: 581 (w.) SURINAM. Neotropic. AntCat AntWiki HOLTaxonomic history
Olivier, 1792: 500 (q.m.); Wheeler, 1949 PDF: 677 (l.).Combination in Myrmica: Latreille, 1804: 179.Combination in Oecodoma: Latreille, 1818a PDF: 224; Lepeletier de Saint-Fargeau, 1835 PDF: 176; Smith, 1858a PDF: 180.Combination in Atta: Fabricius, 1804 PDF: 421; Latreille, 1809 PDF: 129; Leach, 1815: 147; Roger, 1863b PDF: 35.Status as species: Linnaeus, 1767 PDF: 964; De Geer, 1773 PDF: 604; Fabricius, 1775 PDF: 395; Fabricius, 1782: 493; Retzius, 1783 PDF: 76; Fabricius, 1787 PDF: 310; Gmelin, 1790 PDF: 2802; Christ, 1791 PDF: 516; Olivier, 1792: 499; Fabricius, 1793 PDF: 362; Latreille, 1802a PDF: 222; Fabricius, 1804 PDF: 421; Gravenhorst, 1807 PDF: 287; Jurine, 1807 PDF: 274 (in text); Latreille, 1809 PDF: 129; Leach, 1815: 147; Lamarck, 1817 PDF: 97; Latreille, 1818a PDF: 224; Lund, 1831a PDF: 118; Pohl & Kollar, 1832: 14; Lepeletier de Saint-Fargeau, 1835 PDF: 176; Guérin-Méneville, 1844a PDF: 422; Smith, 1858a PDF: 180; Roger, 1863b PDF: 35; Mayr, 1863a PDF: 437; Mayr, 1865 PDF: 81 (redescription); Mayr, 1884 PDF: 37; Emery, 1892c PDF: 162; Dalla Torre, 1893 PDF: 151; Emery, 1894l PDF: 57; Forel, 1895b PDF: 138; Forel, 1899b PDF: 32; Forel, 1905e PDF: 157; Wheeler, 1905c PDF: 130; Wheeler, 1907b PDF: 274; Forel, 1908c PDF: 40; Forel, 1909a PDF: 249; Forel, 1912f PDF: 179; Emery, 1913c PDF: 259; Mann, 1916 PDF: 453; Wheeler, 1916c PDF: 11; Wheeler, 1916f PDF: 326; Crawley, 1916b PDF: 372; Forel, 1921b PDF: 134; Mann, 1922 PDF: 51; Wheeler, 1922e PDF: 14; Wheeler, 1923a PDF: 4; Emery, 1924f PDF: 353; Wheeler, 1925a: 36; Borgmeier, 1927c PDF: 136; Santschi, 1929f PDF: 92 (in key); Borgmeier, 1934 PDF: 108; Menozzi, 1935b PDF: 197; Weber, 1938b PDF: 205; Santschi, 1939f PDF: 166; Borgmeier, 1939 PDF: 422 (in list); Weber, 1941b PDF: 127; Gonçalves, 1942 PDF: 344; Weber, 1945 PDF: 72; Weber, 1946c PDF: 156; Gonçalves, 1947a PDF: 185; Borgmeier, 1950d PDF: 254; Weber, 1958a PDF: 9; Borgmeier, 1959b PDF: 339 (redescription); Kempf, 1961b PDF: 520; Kempf, 1972b PDF: 26; Cherrett & Cherrett, 1989 PDF: 52; Bolton, 1995b: 75; Branstetter & Sáenz, 2012 PDF: 257; Bezděčková et al., 2015 PDF: 115; Fernández et al., 2015 PDF: 99 (redescription); Fernández & Serna, 2019 PDF: 841.Senior synonym of Atta fervens: Smith, 1858a PDF: 180; Mayr, 1863a PDF: 437; Roger, 1863b PDF: 35; Dalla Torre, 1893 PDF: 151; Forel, 1899b PDF: 32; Emery, 1924f PDF: 353; Borgmeier, 1959b PDF: 340; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Senior synonym of Atta grossa: Latreille, 1802a PDF: 224; Fabricius, 1804 PDF: 421; Lepeletier de Saint-Fargeau, 1835 PDF: 176; Smith, 1858a PDF: 180; Mayr, 1863a PDF: 437; Roger, 1863b PDF: 35; Dalla Torre, 1893 PDF: 151; Forel, 1899b PDF: 32; Emery, 1924f PDF: 353; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Senior synonym of Atta cephalotes integrior: Borgmeier, 1959b PDF: 340; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Senior synonym of Atta cephalotes isthmicola: Borgmeier, 1959b PDF: 340; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Senior synonym of Atta migratoria: Retzius, 1783 PDF: 76; Fabricius, 1793 PDF: 362; Fabricius, 1804 PDF: 421; Lepeletier de Saint-Fargeau, 1835 PDF: 176; Smith, 1858a PDF: 180; Mayr, 1863a PDF: 437; Roger, 1863b PDF: 35; Dalla Torre, 1893 PDF: 151; Forel, 1899b PDF: 32; Emery, 1924f PDF: 353; Borgmeier, 1959b PDF: 340; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Senior synonym of Atta cephalotes oaxaquensis: Borgmeier, 1959b PDF: 340; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Senior synonym of Atta cephalotes opaca: Borgmeier, 1959b PDF: 340; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Senior synonym of Atta polita: Borgmeier, 1959b PDF: 340; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Senior synonym of Atta visitatrix: Emery, 1892c PDF: 162; Dalla Torre, 1893 PDF: 151; Forel, 1899b PDF: 32; Emery, 1924f PDF: 353; Kempf, 1972b PDF: 26; Bolton, 1995b: 75; Fernández et al., 2015 PDF: 99.Costa-Rica, San Jose (Biolley, Alfaro). Ile de Coco (Alfaro), evidemment importee.
Como localidade do typo desta espécie deve ser considerada a Guyana Hollandeza (Surinam). Linneu baseou a sua diagnose (1758) sobre material colleccionado por Rolander, sobre o qual diz H. Baillon (1891, Dictionnaire de Botanique, vol. 3, Paris, p. 742): «Voyageur danois à la Guyane. Hornemann a fait connaitre (1812) le journal de son Voyage à Surinam».
Considero como forma typica abundante material de operarios, 1 macho e 1 fêmea de Lelydorp, localidade que fica a uma distancia de 25 km de Paramaribo (Stahei e Geijskes leg. Abril 1938). Também possuo material colleccionado porBünzli em Paramaribo, e por N. A. Weber na Guyana Hollandeza e em Trinidad.
Segundo Santschi (1929, p. 92) a cabeça do operá- rio maior apresenta-se muito dividida pelo sulco occipital, o que não se verifica no material de Surinam. A espécie parece variar, bastante e precisava ser revista.
Sobre a nidificação desta espécie , Stahel e Geijskes publicaram ha pouco (1939, Rev. Ent. X, fasc. 1) importante trabalho.
- Saint-Esteban.
Atta cephalotes is a species of leafcutter ant in the tribe Attini (the fungus-growing ants). A single colony of ants can contain up to 5 million members, and each colony has one queen that can live more than 15 years. The colony comprises different castes, known as "task partitioning", and each caste has a different job to do.[2]
The species is one of the earliest formally classified ants, first described by Swedish zoologist Carl Linnaeus in 1758 as Formica cephalotes in the 10th edition of Systema Naturae together with 16 other ant species, all of which he placed in the genus Formica.[3] It was later transferred to a new genus, Atta, along with five other species by Danish zoologist Johan Christian Fabricius in 1804.[4] In 1911, American entomologist William Morton Wheeler designated A. cephalotes as the type species of Atta.[5] It was also designated as the type species of Oecodoma, but the genus is now a synonym of Atta.[6]
A special caste of workers manages the colony's rubbish dump. These ants are excluded from the rest of the colony. If any wander outside the dump, the other ants will kill them or force them back. Rubbish workers are often contaminated with disease and toxins, and live only half as long as their peers.[7]
The species is widely distributed in the Neotropical region, from Mexico to Bolivia, with disjunct populations in Amazonas and north-eastern Brazil.[8]
Across the rainforest floor they typically occupy an area of approximately 20 square feet. They live in nests that can be as deep as 7 metres that they have carefully positioned so that a breeze can rid the nest of the dangerous levels of CO2 given off by the fungus they farm and eat.[9]
Atta cephalotes is a species of leafcutter ant in the tribe Attini (the fungus-growing ants). A single colony of ants can contain up to 5 million members, and each colony has one queen that can live more than 15 years. The colony comprises different castes, known as "task partitioning", and each caste has a different job to do.
Atta cephalotes (zampopo, zompopo o zompopa) es una de las cuarenta y una especies de hormigas cortadoras de hojas. Esta especie pertenece a la tribu Attini (hormigas que cultivan hongos). Una colonia de hormigas puede estar compuesta por hasta cinco millones de individuos, y cada colonia tiene una reina que puede vivir por más de quince años. La colonia está organizada en varias castas, cada una de las cuales se especializa en una tarea específica.
La reina es de mayores dimensiones que todas las otras hembras y posee alas. Su función es poner los huevos a partir de los cuales nacen las trabajadoras, los machos y las nuevas reinas.
Los machos también tienen alas, y su rol es inseminar a la reina virgen.
Las hormigas no reproductoras son todas hembras y se dividen en varias castas. Los soldados son las hormigas de mayor tamaño y a menudo montan guardia en la entrada del nido o salen en misiones de reconocimiento para avistar depredadores. Las trabajadoras son de dos tipos, media y mínima, ambas poseen grandes mandíbulas y dientes afilados. Las trabajadoras media son las más grandes de los dos tipos, y se dedican a cortar hojas y transportarlas hasta el nido. Estas hormigas poseen la capacidad de orientarse para llegar hasta el sitio con las hojas apropiadas siguiendo el rastro de la esencia de feromonas que liberan las cabezas de las otras hormigas en su recorrido, en un proceso denominado ‘recorrido en tándem’. Una vez que las trabajadoras medias han depositado el material en el nido, unas trabajadoras de porte más pequeño denominadas ‘trabajadoras mínima’ cortan las hojas en trozos más pequeños y luego las colocan como alimento de los hongos que cultivan. Ellas también recubren a las hojas con saliva antibacterial que evita el crecimiento de otros tipos de hongos.
Una casta especial de trabajadoras se ocupa de gestionar el basurero de la colonia. Estas hormigas se encuentran excluidas del resto de la colonia. Si alguna de ellas se aventura fuera del basurero, las otras hormigas la matan o la obligan a regresar al basurero. A menudo las hormigas del basurero se encuentran contaminadas con toxinas y enfermedades, y su vida por lo general es un 50% más corta que la del resto de las hormigas.[2]
Los trabajadores ‘mínima’ son de porte más pequeño y se ocupan de alimentar a toda la colonia de hormigas. Estas trabajadoras mínima también realizan tareas de guardias y siguen a las trabajadoras media o viajan de polizones en la hoja que transportan hasta el sitio desde donde se extraen las hojas y defienden a las trabajadoras media de la acción de parasitoides pequeños denominados moscas foridas.
Las hembras, sean trabajadoras o soldados, son generalmente estériles, pero en algunos casos pueden poner huevos que solo producen machos, por no estar fertilizados.
Las hojas que cortan las hormigas trabajadoras no son para su consumo, ya que les resultan tóxicas a las hormigas. Las hormigas mínima lo utilizan como sustrato para cultivar hongos.
En el suelo de la selva la colonia ocupa un área de unos 6 metros de diámetro. Viven en nidos que pueden llegar a tener siete metros de profundidad, los nidos se encuentran emplazados de forma tal que las brisas ayuden a renovar el aire de la colonia para evitar que se desarrollen niveles peligrosos de CO2 producto de los hongos que cultivan y de los cuales se alimentan.
Las hormigas cortadoras de hojas son especies muy especializadas. La misma es el resultado de un proceso de evolución de veinticinco millones de años durante el cual se ha establecido una relación simbiótica con los hongos que cultivan.
La inseminación en Atta cephalotes precisa del vuelo, y por ello la reina y los machos están dotados de alas. En preparación para el vuelo nupcial, la reina almacena en un buche en su boca algunos hongos para que sirvan de base para el cultivo que deberá establecerse en la nueva colonia. El proceso comienza cuando la reina remonta vuelo. El macho se le une en vuelo y la insemina, luego de lo cual el macho ya no es necesario y muere. La reina se posa sobre el suelo y rápidamente pierde las alas, y pronto comienza a buscar un sitio adecuado para comenzar una nueva colonia. Una vez que encuentra un sitio apropiado, ella comienza a excavar el suelo y libera un poco de los hongos que ella había almacenado con anterioridad de forma de comenzar el proceso en un nuevo sistema subterráneo.
Atta cephalotes (zampopo, zompopo o zompopa) es una de las cuarenta y una especies de hormigas cortadoras de hojas. Esta especie pertenece a la tribu Attini (hormigas que cultivan hongos). Una colonia de hormigas puede estar compuesta por hasta cinco millones de individuos, y cada colonia tiene una reina que puede vivir por más de quince años. La colonia está organizada en varias castas, cada una de las cuales se especializa en una tarea específica.
Atta cephalotes est une espèce de fourmis champignonnistes originaire du Néotropique[1]. Ces fourmis ont la particularité de découper des morceaux de végétaux qu'elles peuvent ensuite transporter sur de longues distances, en file indienne, pour les utiliser comme substrat pour la culture d'un champignon symbiotique qu'elles font pousser au sein de leur fourmilière et qui sert d'apport nutritif pour la colonie, et plus particulièrement pour son couvain.
Atta cephalotes compte parmi les espèces de fourmis présentant un des polymorphismes les plus étendus, les plus petites ouvrières ne pesant que 0,4 mg, contre jusqu'à 110 mg pour les plus grosses[2]. Les tâches effectuées par les ouvrières au sein de la colonie sont largement dépendantes de leur taille.
Les mandibules de cette espèce sont particulièrement acérées, capables de découper très facilement le corps de leurs ennemis (fourmis légionnaires par exemple) ou de trancher la peau humaine, « avec moins de 1% de la force requise si elles étaient faites du même matériau que les dents humaines »[3]. On a récemment (2002, 2021) montré que c'est grâce au zinc[4] à la disposition particulière d'atomes de zinc, produite lors de la biominéralisation de la bordure des « dents » de leurs mandibules ; disposition qui leur donne le tranchant d'un scalpel. Dans Scientific Reports, les auteurs de cette découverte estiment que ce type d'arrangement moléculaire peut être un modèle pour des solutions biomimétiques à la fabrication de tranchants moins couteux et plus durablement affûtés[5].
Ces mandibules finissent toutefois par s'user et les fourmis ayant de telles mandibules (usées) coupent deux fois moins vite que les autres, tout en dépensent deux fois plus d'énergie[6]. Une étude publié en 2011 a montré qu'elles ont alors tendance à porter les feuilles vers le nid, plutôt que les couper[6].
Atta cephalotes est une espèce de fourmis champignonnistes originaire du Néotropique. Ces fourmis ont la particularité de découper des morceaux de végétaux qu'elles peuvent ensuite transporter sur de longues distances, en file indienne, pour les utiliser comme substrat pour la culture d'un champignon symbiotique qu'elles font pousser au sein de leur fourmilière et qui sert d'apport nutritif pour la colonie, et plus particulièrement pour son couvain.
Atta cephalotes is een soort mier uit de familie der Formicidae die voorkomt in Midden- en Zuid-Amerika.
A. cephalotes komt voor in heel Latijns-Amerika. Ze leven er in oerwouden.
Er zijn enkele kastes in deze mierensoort: maagdelijke koninginnen, vruchtbare mannetjes en vrouwtjes (koninginnen) en werksters. Ze leven in kolonies die meer dan een miljoen exemplaren kunnen bevatten. Een kolonie leeft in een grote ondergrondse nesten die met elkaar verbonden zijn. Het nest van de kolonie bevat een kamer waar schimmels groeien. Die dienen als voedsel. De schimmel zelf wordt gevoed door bladeren die de werksters aanbrengen. De werksters proberen de schimmel te beschermen tegen schadelijke micro-organismen.
De koningin is forsgebouwd en is zo'n 30 mm lang. Ze is donkerbruin en gevleugeld. Haar enige rol in de kolonie is het leggen van eitjes. Werksters zijn roodbruin, niet gevleugeld en hebben stekels op hun achterlijf. Ze hebben lange poten en grote kaken met fijne, scherpe tanden. Mannetjes zijn gevleugeld en donkerder dan de vrouwtjes. Zij staan in voor de bevruchting van de koningin, maar spelen verder geen rol in de kolonie.
Binnen de werksters worden nog enkele types onderscheiden:
Werksters die bladeren verzamelen krijgen na verloop van tijd sleet op hun kaken. Ze leggen zich dan exclusief toe op het vervoeren van bladeren die de jongere exemplaren hebben geknipt.[2]
Per nest is er één koningin, zij legt duizenden eitjes per dag. Bevruchte eitjes worden koninginnen of werkster, onbevruchte worden mannetjes. In de meeste gevallen worden werksters geboren. Als het regenseizoen aanbreekt, verlaten vruchtbare mannetjes en vrouwtjes het nest om te paren. Elk vrouwtje paart slechts één keer. Ze kan enkele honderd miljoenen zaadcellen van het mannetje opslaan. Na de paring sterft het mannetjes, de vrouwtjes proberen elk een nieuwe kolonie op te richten. Ze maken daarvoor een tunnel van zo'n 10 cm diep in de grond en starten daar een nieuwe schimmeltuin met wat schimmel uit de oude kolonie dat in een speciale holte in de mond werd bewaard. Ze beginnen er ook met eitjes te leggen. De schimmel wordt eerst gevoed met eitjes en uitwerpselen van de koningin. Dit kan 5 tot 10 weken duren, totdat er werksters zijn die het werk kunnen overnemen. De koningin legt zich vanaf dan toe op de voortplanting. Na 2 tot 3 jaar worden nieuwe vruchtbare exemplaren geboren. Negentig procent van de koninginnen slaagt er niet in een nieuwe kolonie op te richten.
Atta cephalotes is een soort mier uit de familie der Formicidae die voorkomt in Midden- en Zuid-Amerika.
Atta cephalotes (лат.) — вид муравьёв-листорезов из трибы грибководов Attini подсемейства Myrmicinae (Formicidae). Один из самых массовых и доминантных видов беспозвоночных тропической Южной и Центральной Америки[2][3][4]. Из-за регулярного срезания листьев считается одним из опасных видов-вредителей[5].
Центральная и Южная Америка[6]. Встречаются от Мексики на севере ареала до Аргентины на юге[3]: Аргентина, Боливия, Бразилия, Венесуэла, Гайана, Гватемала, Коста-Рика, Колумбия, Куба, Мексика, Никарагуа, Панама, Перу, Суринам, Тринидад, Французская Гвиана, Эквадор[5].
Рабочие муравьи красновато-коричневого цвета имеют размер 2—14 мм, самки до 22 мм. Крупные рабочие (солдаты) имеют большую яйцевидную голову с выемкой на затылке[5][6]. На территории своей колонии муравьи-листорезы Atta cephalotes во время фуражировки срезают от 13 до 20 процентов нового растительного подроста ежегодно. Исследования в Гайане показали, что муравьи фуражируют на расстоянии до 60 м от гнезда и срезают листья и цветы у 36 из 72 видов растений, обнаруженных там[7]. Некоторые мелкие рабочие сидят на кусочках листьев, переносимых более крупными листорезами-фуражирами, защищая их от нападения мелких паразитических мух-горбаток (Phoridae)[8]. В начале сезона дождей крылатые самки и самцы выходят из гнезда и совершают единственный в своей жизни брачный полёт, в ходе которого спариваются. Самцы после этого погибают, а молодые самки основывают новые колонии[9]. Смертность самок на этом самом первом этапе создания новых семей достигает 90 %[5].
Имеют огромные подземные муравейники, численность муравьёв в которых достигает нескольких миллионов особей. В странах тропической Южной и Центральной Америки Atta cephalotes является одним из самых массовых и доминантных видов беспозвоночных[2][3][4].
Для защиты деревьев (особенно садовых культур) от Atta cephalotes существует три основные стратегии: a) защита растения от повреждения муравьями с использованием механических барьеров, b) обнаружение муравейников, их разрушение физическими или механическими средствами, и c), использование фуражировочного поведения муравьёв, собирающих отравленные материалы-приманки и приносящих их в свои гнезда[5].
Хотя этот вид и рассматривается в качестве вредителя, его роль в равновесии экосистем Южной и Центральной Америки является ключевой и складывалась в течение миллионов лет коэволюции с грибами, которые они разводят[10].
Дождь может сильно ограничить фуражировку муравьев различными механизмами, влияющими как на самих муравьёв, так и на маневренность нагруженных рабочих, увеличивая вес их груза. В ходе специальных исследований было проанализировано влияние дождя на фуражировку муравьев с листьями. Политые дождём грузы (кусочки листьев) часто падали, хотя муравьи и не были мокрыми, а политые дождевыми каплями муравьи также сбросили свои грузы, даже если их грузы не были влажными. Смоченные листовые кусочки увеличили свой вес на 143 % и были сброшены фуражирами независимо в отношении их площади или симметрии. Полив тропы не повлиял на долю муравьев, которые сбросили свои нагрузки. Экспериментами было показано, что муравьи-фуражиры увеличивают свою скорость на 30 % после экспериментального увеличения относительной влажности и шума капель дождя на листьях у тропы[11].
Atta cephalotes (лат.) — вид муравьёв-листорезов из трибы грибководов Attini подсемейства Myrmicinae (Formicidae). Один из самых массовых и доминантных видов беспозвоночных тропической Южной и Центральной Америки. Из-за регулярного срезания листьев считается одним из опасных видов-вредителей.
