Bastard bee

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Bastard bee
Dung bee (Eristalis tenax), ♀

Dung bee ( Eristalis tenax ), ♀

Systematics
Class : Insects (Insecta)
Order : Fly (Diptera)
Subordination : Flies (Brachycera)
Family : Hoverflies (Syrphidae)
Genre : Eristalis
Type : Bastard bee
Scientific name
Eristalis tenax
( Linnaeus , 1758)

The dung bee , mud bee or pseudo-bee wedge-spotted hover fly ( Eristalis tenax ) is a common and conspicuous species of hover fly .

features

The dung bee is a large, 14 to 18 millimeter long, bee-like hover fly. Their abdomen is dark brown and has wedge-shaped yellow, ocher or reddish-yellow spots on the second segment. However, the drawing is quite different.

The black compound eyes are connected by hair ties at the top and bottom. The eyes can also be used to distinguish between males and females: in males, the eyes meet on the forehead, in females the eyes are clearly separated from each other.

The unfeathered antenna bristle is important to distinguish it from other Eristalis species .

development

Rat tail larva of the tribe Eristalini

The larvae of the dung bees live in cesspools, septic tanks, in the mud at the edges of pools and in other bacteria-rich, oxygen-poor water with decomposing vegetable substances. They have a long breathing tube that consists of three sections and can be telescoped out to a length of up to 4 cm. With this they get air from the water surface. Because of this tube, they are also called rat tail larvae (name: (Greek) eri- "long", stalis "rod at the front end (here of course the rear end, so to speak stern spit) of the ship"; (lat.) Tenax "tough"). The larvae themselves are about 20 mm in size. They filter bacteria and decaying plant parts from the water and thus also contribute to the clarification of wastewater. Nevertheless, they are fighting for the mass-produced occurrence as they contribute to pupation looking for a dry place to penetrate out of the water and even in homes. Other representatives of the genus Eristalis and the related genus Helophilus also have rat tail larvae.

Occurrence and way of life

Dung bees mating

The bastard bee is common all over the world. It is quite common, especially in rural areas where there are opportunities for their larvae to develop. It got its name because of its frequent occurrence near dung heaps.

The adults mainly fly from March to October, but also in winter on warm days. They particularly like to visit the flowers of the daisy and umbelliferae . The females overwinter.

The dung bee has only a weak escape reflex and can be caught with the hands without any problems. In doing so, she obviously relies on her resemblance to bees, which also shows that a warning costume does not necessarily have to be conspicuous (e.g. yellow-black). In ancient times was superstition that one could bees (for honey) grow by decay an ox on the field can ( spontaneous generation ) - the Flying masse occurring maggots like z. Some of them really produced dung bees, which hardly led to more honey. The rat tail larva can very rarely be the cause of myiasis in mammals (including humans) .

The migratory behavior of the dung bee

Eristalis tenax is a migratory insect and conducts directed seasonal migrations. In autumn, these lead from Central Europe to the south and southwest into the Mediterranean region. The bastard bee crosses the passes of the low mountain ranges, the Pyrenees and the Alps. In the spring, the train is in the opposite direction. The dung bee pulls using favorable and avoiding unfavorable winds. It shows a behavior similar to that of migrating butterflies and birds. The dungbee's migration to the south takes place at low altitudes and is therefore only visible to the eye when there is a headwind and when climbing mountains. The hoverflies try to fly below unfavorable air currents. When the wind from the tail winds, the dung bee moves at great heights over the German low mountain range. Above the Swabian Alb, for example, a strong hover fly migration was detected with special optics at altitudes of 1000–1400 meters above ground (up to 2000 meters above sea level). Birds were also observed up to great heights to hunt hoverflies migrating there. At the Randecker Maar research station on the Swabian Alb, the migrations of hover flies (including the dung bees) have been documented since 1970 and the animals are recorded, determined and counted with the help of fish traps. In the past few years, a sharp decline in the number of animals recorded was noted. The researchers attribute this to the use of toxins in agriculture.

literature

  • Gatter, W. & Gatter D. (1973): Mass migration of the hover fly Eristalis tenax and the ladybird Coccinella septempunctata on the Randecker Maar, Swabian Alb . Century Ges. Naturkde. Württ. 128: 151-154.
  • Gatter, W. (1975): Regular autumn migrations of the hover fly Eristalis tenax on the Randecker Maar, Swabian Alb . Atalanta 6: 193-200.
  • Gatter, W. & Gatter, D. (1976): The migration of hover flies after scheduled catches on the Randecker Maar (Swabian Alb) (Diptera, Syrphidae) . Atalanta 7: 4-18.
  • Gatter, W. (1981): Adaptations of migrating insects to the daily rotation of the wind . Century Ges. Naturkde. Württbg. 136: 191-202.
  • Gatter, W. (1981): Insect migration. News about the migration behavior of insects. About the requirements of the West Palaearctic migration system ; Kilda Publishing House. Greven. 94 pages; [1]
  • Schmid, U. & Gatter, W. (1988): The occurrence of hover flies on the Randecker Maar - a faunistic overview (Diptera, Syrphidae) . Message Bayer. Ent. 37: 117-127.
  • Gatter, W., Schmid U. (1990): The migration of hover flies (Diptera, Syrphidae) on the Randecker Maar. Festschrift 20 years of Randecker Maar station ; Spixiana Suppl. 15: 100 pages; [2]

Individual evidence

  1. ^ W. Jacobs & M. Renner: Biology and Ecology of Insects 4th Edition, further edited by H. Bellmann & K. Honomichl. Gustav Fischer Verlag, Stuttgart 2007. ISBN 978-3-8274-1769-5 . Page 606.
  2. ^ E. Stresemann: Excursion fauna of Germany. Invertebrates: insects - 2 part. 7th edition, edited by H.-J. Hannemann. B. Klausnitzer & K. Senglaub. Gustav Fischer Verlag Jena, Stuttgart 1994. ISBN 3-334-60824-7
  3. ↑ cf. e.g. P. Ovidius , Metamorphoses XV, 364 ff.
  4. ↑ Ulrich Schmid: 275 popular misconceptions about plants and animals. Kosmos, 2002
  5. ↑ cf. for example: A. Aguilera et al .: Intestinal myiasis caused by Eristalis tenax. - Journal of Clinical Microbiology 37: p. 3082. 1999
  6. ^ Gatter W. & Schmid U. (1990): The migration of hover flies (Diptera, Syrphidae) on the Randecker Maar. Festschrift 20 years of Randecker Maar station. Spixiana Suppl. 15, p. 22
  7. ↑ Gatter, W. (1981): The forms of migration of insects. Ent. Journal 91: 1-16
  8. ^ Gatter, W. (1981): Insect migration. News about the migration behavior of insects. About the prerequisites of the west Palaearctic migration system. Kilda Publishing House. Greven, p. 61
  9. ^ Gatter, W. & Gatter D. (1973): mass migration of the hover fly Eristalis tenax and the ladybird Coccinella septempunctata on the Randecker Maar, Swabian Alb. Century Ges. Naturkde. Württ. 128: 151-154
  10. ^ Gatter, W. (1975): Regular autumn migrations of the hover fly Eristalis tenax at the Randecker Maar, Swabian Alb. Atalanta 6: 193-200.
  11. ^ Gatter W. & Schmid U. 1990: The migration of hover flies (Diptera, Syrphidae) on the Randecker Maar. Festschrift 20 years of Randecker Maar station. Spixiana Suppl. 15, p. 76
  12. ^ Gatter, W. (1978): Plan observations of the visible migration on the Randecker Maar as an example of ornithological-entomological research. Bird World 99: 1–21
  13. ↑ Gatter, W. (1981c): Adaptations of migrating insects to the daily rotation of the wind. Century Ges. Naturkde. Württbg. 136: 191-202
  14. ^ Gatter, W. (1981): Insect migration. News about the migration behavior of insects. About the prerequisites of the west Palaearctic migration system. Kilda Publishing House. Greven, pp. 51 and 53.
  15. ^ Gatter W. & U. Schmid 1990: The migration of hover flies (Diptera, Syrphidae) on the Randecker Maar. Festschrift 20 years of Randecker Maar station. Spixiana Suppl. 15, p. 94
  16. ^ Gatter W. & U. Schmid 1990: The migration of hover flies (Diptera, Syrphidae) on the Randecker Maar. Festschrift 20 years of Randecker Maar station. Spixiana Suppl. 15, pp. 11, 12, 14
  17. ↑ Gatter, W. & D. (1976): The migration of hover flies after scheduled catches on the Randecker Maar (Swabian Alb) (Diptera, Syrphidae). Atalanta 7: 4-18
  18. ↑ Schmid, U. & Gatter, W. (1988): The occurrence of hover flies on the Randecker Maar - a faunistic overview (Diptera, Syrphidae). Message Bayer. Ent. 37: 117-127
  19. ↑ Stuttgarter Zeitung, Sept. 14, 2017: The butterflies no longer fly
  20. ↑ http://www.randecker-maar.de/Pressemappe/Presse_23.htm

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