This species appears to be a specialized associate of small Attini (Wheeler 1925, Brandao 1990, Adams et al. 2000), a habit possibly shared with other species of Megalomyrmex such as wettereri, mondabora, and silvestrii. Wheeler (1925) found numerous colonies nesting with Sericomyrmex amabilis on Barro Colorado Island, Panama. He observed a number of colonies in the lab, and made the following observations:The colonies of the Cepobroticus [Megalomyrmex symmetochus] so frequently found living with Sericomyrmex amabilis were decidedly less populous than those of their host. The largest comprised less than 75 individuals, and often the number did not exceed 40 or 50. In every nest a dealated mother queen was present. She usually took up her station, surrounded by a group of her workers, in one of the crypts of the fungus garden a short distance - half to three quarters of an inch - from the Sericomyrmex queen. The guest ants kept their brood in small clusters scattered through the garden and each cluster was cared for by a few workers. Although the ants and their brood were thus intermingled, the workers of each species lavished their attention exclusively on their own eggs, larvae and pupae and were never seen even to transport the progeny of the other species from one part of the garden to another.The workers and queens of Cepobroticus are rather alert and move about more rapidly than their hosts. They devote so much time to licking and fondling one another that the observer is somewhat astonished to find them paying little or no attention to the fungus-growers. As a rule the two species are indifferent to one another. One may watch them for hours without observing anything more than rather distant, mutual antennal salutations. On rare occasions a worker Cepobroticus may be seen licking the gaster of a Sericomyrmex worker or of the sluggish queen. More frequently one of the host workers may be observed in the act of lavishing similar but more elaborate attentions on a Cepobroticus worker. The fungus-grower begins by licking the feet or tarsi, the tibiae and femora, then the thorax or abdomen and finally the head and even the mandibles of the guest. During this operation the latter remains motionless and inclines its body somewhat to one side.The Sericomyrmex never feed their guests by regurgitation. This is not surprising because they never feed one another thus, but resort individually to the growing fungus bromatia. When hungry the Cepobroticus workers and queen also crop the fungus mycelium, but they do this rather roughly, using their mandibles and even shaking or disturbing the substratum. The guests very rarely transport or rearrange the particles of the substratum or take the slightest interest in the garden, except as a source of nourishment. Only on one occasion did I see a Cepobroticus carry a particle of the substratum to another spot, insert it and pat it down with her fore feet. When fresh fruit was introduced into the nest, it was much less frequently visited and eaten by the guests than by their hosts.
Brown observed a colony from near Manaus, Brazil (reported as silvestrii in Kempf and Brown 1968; reidentified as symmetochus by Brandao 1990). Brown reported "The colony ... was found in a small rotten log in rain forest on 26.VIII.1962, in a small chamber with a small species of Trachymyrmex. The ants of both species were found throughout the fungus garden of the chamber, but off to one side in a small chamber was found a group of the Trachymyrmex clustered with a small piece of fungus garden unoccupied by Megalomyrmex. ... the situation suggested that the M. silvestrii colony had successfully attacked and moved into the attine nest, and was in the process of plundering it."
Brandao (1990) reported a collection from Belem, PA, Brazil, from a nest of an unidentified Trachymyrmex.
At La Selva, alate queens and males have been collected at blacklights. Males and queens were common at the lab clearing blacklight on 4 Aug 1992. A lone worker was obtained by Ronald Vargas, during general collection of ants from trail surfaces and low vegetation.
Bolivia, Brazil, Panama, Costa Rica. Costa Rica: Atlantic lowlands.
Taxonomic history
Wheeler & Wheeler, 1955c PDF: 126 (l.); Boudinot et al., 2013 PDF: 63 (w.q.m.).See also: Brandão, 1990b PDF: 445.Megalomyrmex symmetochus és una espècie de formiga de la subfamília Myrmicinae endèmica de Panamà. L'espècie Megalomyrmex symmetochus va ser descoberta per William M. Wheeler a finald de juliol de 1924 a l'illa de Barro Colorado.
Les obreres tenen entre 3 i 3,5 mil·límetres de llarg, amb petits i febles ulls convexos, que s'adapten probablement a la vida a dins dels jardins foscos on habiten. De vegades presenten ocels molt petits. Les obreres són de color vermell groguenc, amb les mandíbules i algunes altres parts de color marró.
La femella té gairebé 4 mil·límetres de llarg. Té ulls més grans que les obreres i els ocels diferents. Si no, semblen molt semblants a les obreres. Cada ocel té un marge negre internament. Les ales són hialines i iridescents, de color groguenc, amb les venes i el pterostigma groc pàl·lid. Les membranes de les ales són distintament pubescents.
Els mascles fan gairebé 3 mil·límetres de llarg. Tenen ulls i ocels molt grossos. El seu cos és molt semblant al de les obreres i les femelles, però amb els costats del tòrax llisos. Les ales tenen pubescències més llargues que en les femelles. Els mascles són de color marró groguenc, amb antenes i potes lleugerament més pàl·lides. Els ulls i un punt al llarg de la frontera interna de cada ocel són negres.
Megalomyrmex symmetochus és una espècie de formiga de la subfamília Myrmicinae endèmica de Panamà. L'espècie Megalomyrmex symmetochus va ser descoberta per William M. Wheeler a finald de juliol de 1924 a l'illa de Barro Colorado.
Les obreres tenen entre 3 i 3,5 mil·límetres de llarg, amb petits i febles ulls convexos, que s'adapten probablement a la vida a dins dels jardins foscos on habiten. De vegades presenten ocels molt petits. Les obreres són de color vermell groguenc, amb les mandíbules i algunes altres parts de color marró.
La femella té gairebé 4 mil·límetres de llarg. Té ulls més grans que les obreres i els ocels diferents. Si no, semblen molt semblants a les obreres. Cada ocel té un marge negre internament. Les ales són hialines i iridescents, de color groguenc, amb les venes i el pterostigma groc pàl·lid. Les membranes de les ales són distintament pubescents.
Els mascles fan gairebé 3 mil·límetres de llarg. Tenen ulls i ocels molt grossos. El seu cos és molt semblant al de les obreres i les femelles, però amb els costats del tòrax llisos. Les ales tenen pubescències més llargues que en les femelles. Els mascles són de color marró groguenc, amb antenes i potes lleugerament més pàl·lides. Els ulls i un punt al llarg de la frontera interna de cada ocel són negres.
Megalomyrmex symmetochus is a species of ant in the subfamily Myrmicinae. It is native to Panama.[1]
M. symmetochus was discovered by William M. Wheeler in late July 1924 in the fungus gardens of the attine Sericomyrmex amabilis of Barro Colorado Island.[2]
Workers are 3 to 3.5 mm long, with small, feebly convex eyes, that are probably adapted to living within the dark fungal gardens of their host. Very small ocelli are only sometimes present. Workers are yellowish red, with mandibles, funiculi, the posterior half of the first segment of the gaster and the sutures of the thorax and pedicels brown. The tip of the gaster is yellowish.[2]
The female is almost 4 mm long. She has larger eyes than the workers and distinct ocelli. Otherwise, they look very similar to workers. Each ocellus has a black margin internally. The wings are yellowish hyaline and iridescent, with veins and pterostigma pale yellow. The membranes of the wings are distinctly pubescent.[2]
Males are almost 3 mm long. They bear very large eyes and ocelli. Their body form is very similar to that of workers and females, but with smooth sides of the thorax. The wings have longer pubescence that in the female. Males are brownish yellow, with a little darker gaster and slightly paler antennae and legs. The eyes and a spot along the inner border of each ocellus are black.[2]
M. Symmetochus often live among and take from the gardens of fungus-growing ants, sometimes usurping the gardens.[3] In some populations they coexist with fungus-growing hosts>80% of the time.[4] They number their hosts as much as 1:3.[5] Young queens stealthily invade fungus-growing colonies and start their own lineage in the fungus garden.[6] Then, they clip the wings of the hosts' virgin queens, but not the males.[6]
When their hosts live near predators who destroy the nests and destroy their gardens, M. Symmetochus serves as protection of their host colonies. Hundreds of worker ants live throughout the nest of the host, and when invaders attack, individuals recruit the others inside to defend the nest. Also, these ants have been observed projecting their stings, leaving two isomers of 3-butyl-5-hexylpyrrolizidine, marking the nest with the scent of its toxin.[5] It seems that some species avoid nests with their marked scent. When there are no invaders, M. Symmetochus commonly have aggressive conflict with their hosts.[6] Therefore, it seems that when M. Symmetochus lives with a host with no outside danger, they serve as parasites, but when the hosts live near other threats, they have a mutualistic relationship with their hosts.[5]
Megalomyrmex symmetochus is a species of ant in the subfamily Myrmicinae. It is native to Panama.
M. symmetochus was discovered by William M. Wheeler in late July 1924 in the fungus gardens of the attine Sericomyrmex amabilis of Barro Colorado Island.
Megalomyrmex symmetochus es una especie de hormiga de la subfamilia Myrmicinae. Es endémica de Panamá.
La especie Megalomyrmex symmetochus fue descubierta por William M. Wheeler a finales de julio de 1924 en la isla de Barro Colorado.
Las obreras tienen entre 3 y 3,5 milímetros de largo, con pequeños y débiles ojos convexos, que se adaptan probablemente a la vida dentro de los cultivos de hongos oscuros donde habitan. A veces presentan ocelos muy pequeños. Las obreras son de color rojo amarillento, con las mandíbulas y algunas otras partes de color marrón.
La reina tiene casi 4 milímetros de largo. Tiene ojos más grandes que las obrera y los ocelos distintos. Fuera de eso son muy similares a las obreras. Cada ocelo tiene un margen negro internamente. Las alas son hialinas e iridiscentes de color amarillento, con las venas y el pterostigma amarillo pálido. Las membranas de las alas son distintamente pubescentes.
Los machos tienen casi 3 milímetros de largo. Tienen ojos y los ocelos muy grandes. Su cuerpo es muy similar al de las obreras pero con los lados del tórax lisos. Las alas tienen pubescencias más largas que en las reinas. Los machos son de color marrón amarillento, con antenas y patas ligeramente más pálidas. Los ojos y un punto a lo largo del borde interno de cada ocelo son negros.
Megalomyrmex symmetochus es una especie de hormiga de la subfamilia Myrmicinae. Es endémica de Panamá.
La especie Megalomyrmex symmetochus fue descubierta por William M. Wheeler a finales de julio de 1924 en la isla de Barro Colorado.
Megalomyrmex symmetochus (Wheeler, 1925) è una formica appartenente alla sottofamiglia Myrmicinae.[1] Questa specie è presente e quindi parassita circa l'80% dei nidi della Sericomyrmex amabilis.
Secondo uno studio dell'università di Copenhagen[2], insediandosi all'interno dei giardini di coltivazione dei funghi della specie ospite si viene a creare un beneficio per entrambe le specie. I ricercatori danesi hanno infatti dimostrato che le colonie parassitate dalla Megalomyrmex sono protette da attacchi di altre specie sterminatrici. In questo modo la Megalomyrmex si comporta quasi come una casta guerriera o come dei mercenari ben armati assoldati dagli indifesi coltivatori.
È una formica di colore rossastro, la lunghezza varia dai 3 ai 3,5 mm per le operaie, le regine sono intorno ai 4 mm mentre i maschi intorno ai 3 mm.
L'alimentazione preferenziale della M. symmetochus è costituita dalle sostanze proteiche che ricava dai funghi che coltivano altre specie e dalle larve della specie ospite[3].
Sono state identificate in America centrale, più precisamente a Panama. È stata trovata all'interno dei nidi di altre specie, come la coltivatrice di funghi Sericomyrmex amabilis.
Megalomyrmex symmetochus (Wheeler, 1925) è una formica appartenente alla sottofamiglia Myrmicinae. Questa specie è presente e quindi parassita circa l'80% dei nidi della Sericomyrmex amabilis.
Secondo uno studio dell'università di Copenhagen, insediandosi all'interno dei giardini di coltivazione dei funghi della specie ospite si viene a creare un beneficio per entrambe le specie. I ricercatori danesi hanno infatti dimostrato che le colonie parassitate dalla Megalomyrmex sono protette da attacchi di altre specie sterminatrici. In questo modo la Megalomyrmex si comporta quasi come una casta guerriera o come dei mercenari ben armati assoldati dagli indifesi coltivatori.
Megalomyrmex symmetochus is een mierensoort uit de onderfamilie van de Myrmicinae.[1][2] De wetenschappelijke naam van de soort is voor het eerst geldig gepubliceerd in 1925 door Wheeler, W.M..
Bronnen, noten en/of referenties
Megalomyrmex symmetochus é uma espécie de insecto da família Formicidae.
É endémica do Panamá.
Megalomyrmex symmetochus é uma espécie de insecto da família Formicidae.
É endémica do Panamá.
Megalomyrmex symmetochus là một loài kiến thuộc phân họ Myrmicinae. Đây là loài đặc hữu của Panama.
M. symmetochus đã được khám phá bởi William M. Wheeler cuối tháng 7 năm 1924 trong vườn nấm của loài attine Sericomyrmex amabilis Wheeler, 1925 của đảo Barro Colorado. Con thợ dài từ 3-3,5 mm.
Megalomyrmex symmetochus là một loài kiến thuộc phân họ Myrmicinae. Đây là loài đặc hữu của Panama.
M. symmetochus đã được khám phá bởi William M. Wheeler cuối tháng 7 năm 1924 trong vườn nấm của loài attine Sericomyrmex amabilis Wheeler, 1925 của đảo Barro Colorado. Con thợ dài từ 3-3,5 mm.
Megalomyrmex symmetochus Wheeler, 1925
Megalomyrmex symmetochus (лат.) — вид муравьёв рода Megalomyrmex из подсемейства мирмицины (Myrmicinae, Solenopsidini). Южная и Центральная Америка: Коста-Рика, Никарагуа, Панама, Перу. Включён в Международную Красную книгу как уязвимый вид[1][2].
Мелкие муравьи (около 3 мм) красновато-коричневые цвета, гладкие и блестящие. Ширина головы самок (HW) 0,60-0,84 мм, длина головы (HL) 0,75-0,89 мм, длина скапуса усика (SL) 0,69-0,84 мм. Усики рабочих 12-члениковые с булавой из 3 сегментов. Формула нижнечелюстных и нижнегубных щупиков самок 3,2. Жвалы с несколькими зубцами (около 6). Жало развито. Стебелёк между грудкой и брюшком состоит из двух члеников: петиоля и постпетиоля. Заднегрудка без проподеальных зубцов. На нижней стороне постпетиоля развит длинный зубец. M. symmetochus ассоциирован с грибководами рода Sericomyrmex. Некоторые другие виды рода Megalomyrmex известны как специализированные социальные паразиты муравьёв-листорезов Attini, в гнёздах которых обитают и питаются в грибных садах вида-хозяина. Например, вид Megalomyrmex mondaboroides ассоциирован с грибководами рода Trachymyrmex (C. costatus Mann) и Apterostigma (A. goniodes Lattke). Вид был впервые описан в 1925 американским мирмекологом профессором Уильямом Уилером (англ. Wheeler William M.), а его валидный статус подтверждён в ходе ревизии в 2013 году американскими мирмекологами Брендоном Будино (Brendon E. Boudinot), Теодором Самнихтом (Theodore P. Sumnicht; University of Utah, Солт-Лейк-Сити, Юта, США) и Рашель Адамс (Rachelle M. M. Adams; Department of Entomology Smithsonian Institution, Вашингтон, США). Таксон включён в видовую группу Megalomyrmex silvestrii-group вместе с видами M. fungiraptor, M. mondabora, M. adamsae, M. mondaboroides, M. nocarina, M. silvestrii, M. reina, M. wettereri[1][2][3].
Megalomyrmex symmetochus (лат.) — вид муравьёв рода Megalomyrmex из подсемейства мирмицины (Myrmicinae, Solenopsidini). Южная и Центральная Америка: Коста-Рика, Никарагуа, Панама, Перу. Включён в Международную Красную книгу как уязвимый вид.
