Formica polyctena

Worker of Formica polyctena

The Kahlrückige wood ant (Formica polyctena ) belongs to the genus of wood ants (Formica ), in the subfamily of ants scales ( Formicinae ). It is also known as Little Red Wood Ant.

Features

Head, mesosoma and Stielchenglied are colored predominantly red. The gaster and the top of the head are black. Cheeks and head shield are black brown, as well as the legs, which only at the joints a reddish tint. The two black spots on pronotum and mesonotum are blurred circumscribed and often indistinctly visible.

This ant is only slightly hairy on the head and back, unlike the red wood ant (Formica rufa), with which it is very easy to confuse. So it is most often completely pronotum glabrous or contributes more than 15 bristles. At the head underside it has a maximum of seven short hair and her Stielchenglied has only a few protruding hairs.

While the queens and males can reach a body length from nine to eleven millimeters, the body length is four to 8.5 millimeters for the workers. The reproductives swarm between late April and June.

Distribution and habitat

The Kahlrückige Waldameise settled Laubwaldungen and coniferous forests of all kinds and also lives in pure spruce forests; On sunny forest edges they appear numerous, but penetrates in contrast to the red wood ant (Formica rufa) even deeper into the forest stock one. The area of ​​distribution extends from Iberia to Lake Baikal. In Europe, the area extends from 42 degrees to about 61 degrees north latitude. In mountains it comes at altitudes up to 1,000 meters before.

Way of life

Almost all nests are polygynous. Nests, in which few or live a queen, are very rare. In the spring swarming ants. After mating, which immediately follows the shoals, the young queens are faced with two options: You can go into a nest of their own species or establish a new colony, by penetrating into a nest of gray black slaves ant ( Formica fusca ), the Formica fusca kill - queens and lay eggs themselves. If a colony has become too large, " offshoot nests " form. These remain connected for several years with the " mother 's Nest".

Nutrition

The food of Formica polyctena consists mainly of honeydew and insects, other sweet juices (such as nectar or tree sap ) and plant seeds ( elaiosomes ) are taken.

Nesting

The anthill is built around an old tree stump, but the nest base is under the earth. Building materials are needles and small branches. The needle pile provides a heat storage for the ants Represents the nest can reach a circumference of up to three meters.

Threats and conservation

The Kahlrückigen wood ants and their nests are particularly protected in Germany by the Federal Species Protection Ordinance. This type is valid according to the Red List of Germany as endangered ( category 2).