Post by Deleted on Oct 2, 2011 22:43:11 GMT 1
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| [bg=fbd9bd] Taxonomy: Formicinae Formica (Raptiformica) sanguinea var. aserva Colony type: Polygynous Colony founding: Temporary social parasite Color: Bicolored; dark brown abdomen, red-brown thorax and head. Queens are often darker. Males are black. Size: Worker 4-8 mm / Queen 8-10 mm / Male 8mm Distribution: Throughout United States (absent in the Southeast), Canada Mating season: July Nutrition: Insects, honey/sugar water Temperature: 20-27 degrees C Hibernation: Recommended Air humidity: 10%-40% (moderate) Nest building: Very flexible Planting: Not necessary Class: Easy First described by: Forel (1901) Description: Worker: “Closely related to the typical European form. Clypeal notch rather shallow; clypeal carina more distinct and the surface of the clypeus more convex. Mesoëpinotal constriction a little shallower than in the typical sanguinea. Antennal scapes slender at the base, somewhat enlarged towards their tips. Head relatively large in large workers, almost broader than long, excluding the mandibles, with convex sides, rounded posterior corners and straight or feebly excised superior border. Sculpture a little finer than in the typical sanguinea; head and gaster more shining; punctures on the occiput rather distinct, scattered. Hairs yellowish, very sparse, usually absent on the thorax and petiole; short on the gaster. Pubescence shorter and more dilute than in the typical sanguinea, so that the surface, especially that of the gaster, appears more shining; very fine and appressed on the legs and scapes. Color brownish red like that of deeply colored specimens of the typical form; posterodorsal portion of head and often also the middle of the pronotum infuscated or blackened.” Wheeler (1913) Queen: “Sculpture, pilosity, and color as in the worker; metanotum, posterior border of pronotum and scutellum and three spots on the mesonotum dark brown or black. Head, excluding the mandibles, as broad as long, broader behind than in the front, with strait posterior and lateral borders. Scale of petiole broad, much compressed anteroposteriorly, with thin, sharp, entire or feebly emarginate border. Wings colored as in the typical sanguinea.” Wheeler (1913) Male: “Mandibles broad, dentate. Clypeus convex, carinate; emargination of its anterior border feeble but distinct. Petiole thick, with rather sharp, transverse border. Hairs and pubescence very short and sparse, so that the thorax and gaster are more shining than in the typical sanguinea; head, including the mandibles, opaque. Body and antennae black; tips of the mandibles brownish; legs brownish yellow. Genitalia rather deeply infuscated. Wings colored like those of the female.” Wheeler (1913) |
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| [bg=fbd9bd] This species is in the sanguinea group of Formica and is a particularly close relative of Formica sanguinea. Colonies most often occur in sunny forest clearings, or on the borders of forests. Their nesting habits are quite varied, but nests are often excavated in sandy soil, banked with thatch. Formica aserva is a facultative slave-raider of other Formica; mature colonies do not require slaves, and it’s not uncommon for nests to be entirely independent. Nuptial flights occur in late June and July. Once mated, a queen seeks out an incipient Formica colony and forces her way inside. There, she secures a number of the host’s pupae and guards them fiercely, driving away or killing the resident colony in the process. Feeding on surplus brood, she may begin to lay her own eggs as soon as the first host worker ecloses. The name Formica aserva is synonymous with the less-commonly used "Formica subnuda." |
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| [bg=fbd9bd] Formica aserva is a temporary social parasite and cannot found colonies independently; they need the pupae of other Formica. One or more queens should be given a dozen pupae to begin with, and will benefit from additional host brood later. Unlike many other social parasites, queens should be able to open up cocoons by themselves. Eastern varieties of F. aserva favor Formica glacialis as their host species. |
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| [bg=fbd9bd] The nesting habits of this species in the wild are very flexible. They may live in soil, rotting wood, under rocks, or build thatch mounds. They are reputed to change nest sites often, so colonies might benefit from the presence of a satellite nest. Any common formicarium should suit this species well. A tank setup with thatch present may encourage the construction of mounds by mature colonies. Many have suggested attaching colonies of other Formica to sanguinea-group setups in order to observe raids. Unlike Polyergus, slave-raiding Formica are known to be merciless when attacking other nests, and the queens of these colonies are often killed. |
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| [bg=fbd9bd] There is nothing particularly special about their diet. These ants are highly insectivorous and should accept what you can offer them. |
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| [bg=fbd9bd] An active and aggressive species, Formica aserva will periodically mount organized raids on the colonies of other Formica. Sanguinea group Formica are adapted with enlarged Durfour's glands, which emit relatively large quantities of panic-inducing alarm pheromones on command. The resulting hysteria causes the targeted Formica defenders to fall apart and flee, leaving much of their brood to be harvested by raiders. Stolen brood from these raids are often used as food for the nest, but any surviving pupae will become workers for the raider's colony. While Polyergus will spare the queens of a raided nest so that it might be harvested again, Formica aserva and related species treat these colonies as rivals, and will kill any queens that they might encounter. Sanguinea group Formica have different strategies for attacking different species of host. Workers will bite and use formic acid when threatened, but these ants aren't large enough to be harmful. Unlike their cousins from the rufa group of Formica, Formica aserva will not spray acid into the air when defending their nest. Colonies are often founded singly, but mature nests will accept their own mated queens back into the colony after nuptial flights, and perhaps the queens of other nests too. Formica aserva does not adopt queens to the same magnitude as their rufa cousins. |
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| [bg=fbd9bd] Formica aserva lives in a wide variety of habitats and some do not experience particularly cold winters. It is recommended that you treat your colony according to the environment your queen was collected from. |
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