Straw flies
| Straw flies | ||||||||||||
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Chlorops sp. |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Chloropidae | ||||||||||||
| Rondani , 1856 |
The straw flies (Chloropidae) are a family of the two-winged (Diptera) and belong to the flies (Brachycera). Around 2000 species of this group of animals live around the world, 178 of which are known from Germany. They are mostly small flies with a body length of about two millimeters.
features
The shoot flies are mouthparts greatly stunted the front wings and the like all Diptera to halteres ( halteres ) shaped hind wings can be much reduced form. In many species there is a clear sexual dimorphism , with the males having strongly thickened feet ( tarsi ) of the forelegs and very hairy lower legs ( tibia ) of the fore and middle legs. These differences presumably have a meaning in the mating process, but details are not known.
Way of life
Straw flies are mainly found in meadows, with some species appearing in large numbers, especially in autumn. Since they do not fly, they wander around and in this way also penetrate houses where they can become a nuisance, for example the black and yellow species Thaumatomyia notata , which becomes about 2 mm long. They feed primarily on nectar and honeydew, as well as other sweet liquids.
Larval development
The larvae mostly live inside living plants, especially in grasses, but also on flowers or fruits and fungi; some species can also form galls . There are also species that live in dead plant remains or coprophagous on excrement. Some species are also hunters, such as Thaumatomyia notata , which feeds on gall-dwelling aphids, or species of the genus Siphorella , which hunt in clusters of spiders, and Goniopsita , which hunt in clusters of grasshoppers . Many species are very unspecific when it comes to food choices, others are food specialists (such as Lipara species in reeds ). Some species can be very harmful, especially in cereals.
Types (selection)
Reed Gall Fly ( Lipara lucens )
The reed gall fly, also known as the cigar fly, is about seven millimeters long. The adult animals can be found on reed leaves ( Phragmites australis ) from May to June . Here they generate vibrations that are carried on through the reed leaf and serve to find a partner. The first vibrations are generated by females, and within ten minutes they emit one or two vibrations for eight seconds. Males sitting on the same leaf also react to these vibrations with vibratory jolts, to which the female responds. In this way the male seeks out the female and eventually finds her. The call vibrations of the females are very similar to those of other species, while those of the males differ significantly. The mechanism of the generation of vibrations has not yet been clarified.
The egg is placed on the tip of the reed and the maggot eats its way into the sprouting zone. This destroys the plant's vegetation cone, which stops the reed from growing in length. There is compression and thickening of several (10 to 15) areas ( internodes ) of the reeds and a strong development of the leaf sheaths . The resulting bile resembles a cigar (hence the name cigar fly) and is around 15 millimeters thick and up to 25 millimeters long. Pupation of the larvae takes place in the bile, which is left in the spring. Often other stalk fly species live in the abandoned galls as fecal eater or other insects such as digger wasps or bees .
Fritfly ( Oscinella frit )
The fritflies are black with yellowish limbs and red eyes. In Central Europe they can be found in three generations. The spring form usually sits on the flowers of the dandelion or winter rape . The females, optically oriented at a distance and olfactory nearby, fly to large sprouting grasses such as maize , oats or barley to lay their eggs. Here it lays several eggs along the leaf sheaths, the hatching larvae penetrate the heart, causing the heart leaf to wither. Pupation also takes place at the feeding place. The second generation flies from June and mainly uses oats as an egg-laying place, whereby the eggs are laid loosely in the panicles . When the larvae eat , the ear becomes pale (white-nourished) and the grains wither. The third generation of the year flies in August to September and lays the eggs on various winter grasses. About 60 host grasses are known for this species.
Yellow Wheat Stalk Fly ( Chlorops pumilionis )
The yellow stalk fly is found on various grasses, especially wheat and barley. In Central Europe she brings out two generations. The first generation comes out in May and lays the eggs on the upper parts of the plant of the host grasses, the larvae eat their way down to the ear and then on to the stalk knot. Pupation takes place here. The second generation of the year flies in August to October and lays the eggs in the winter seeds of the cereal species as well as in various wild grasses, especially the couch grass . Hibernation occurs as a larva in the area of the root neck.
Russian straw fly ( Meromyza saltatrix )
The Russian stalk fly, also known as the thigh fly, is characterized by its particularly thick thighs, the muscles of which allow jumping. The way of life as well as the host grasses largely correspond to the yellow wheat stalk fly. However, the pupa is hung in the leaf sheaths with spider threads.
More types
- Crooked-winged stalk fly ( Camarota curvipennis )
- Cetema cereris
Fossil evidence
Fossil evidence of this family is extremely rare. The oldest representative of the straw flies was found in the amber of the Lower Cretaceous Lebanon . This fossil is considered therefore to be the oldest evidence of the pooled to the families of the Schizophora Cyclorrhapha ( cyclorrhapha ). All other evidence comes from tertiary amber deposits, especially the Eocene Baltic amber .
literature
- Willi Hennig : Diptera, two-winged one. In: Handbuch der Pflanzenkrankheiten, V (2), 1st edition (5th edition). Hamburg-Berlin 1953.
- GM Hoffmann, H. Schmutterer: Parasitic diseases and pests on agricultural crops. Stuttgart 1983.
- K. Honomichl, H. Bellmann: Biology and ecology of the insects. CD-Rom, Gustav Fischer Verlag, Stuttgart 1994.
Web links
- www.naturbildarchiv-guenter.de Picture story on the biology and networking of the reed gall fly Lipara lucens
Individual evidence
- ↑ http://vorarlberg.orf.at/news/stories/2762329/ Halmfliegen- "Invasion" in Bludenzer Hochhaus, orf.at, March 14, 2016, accessed March 14, 2016.
- ↑ George O. Poinar, Jr .: Life in Amber . 350 pp., 147 figs., 10 plates, Stanford University Press, Stanford (Cal.) 1992. ISBN 0-8047-2001-0
- ↑ http://hbs.bishopmuseum.org/fossilcat/fosschlorop.html fossil Diptera