Phylum Arthropoda (Arthropods) ➔ Subphylum Hexapoda (Hexapods) ➔ Class Insecta (Insects) ➔ Order Diptera (True flies) ➔ Family Syrphidae (Hoverflies)

Eristalis (Eoseristalis) interrupta (Poda, 1761)

Mittlere Keilfleckschwebfliege

Synonyms and other combinations:

Conops fuscus Scopoli, 1763 | Eristalis carelica Kanervo, 1938 | Eristalis inornatus Loew, 1866 | Eristalis sylvarum Meigen, 1838 | Musca lineolae Harris, 1776 | Musca obfuscata Gmelin, 1790 |

  • Eristalis interrupta, mating  1092
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, mating
    DE, Chemnitz, Hutholz; 2009-09-06 11:24:18
    Image number: 1092
    mating
    DE, Chemnitz, Hutholz
    2009-09-06 11:24:18

  • Eristalis interrupta, mating  1093
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, mating
    DE, Chemnitz, Hutholz; 2009-09-06 11:22:24
    Image number: 1093
    mating
    DE, Chemnitz, Hutholz
    2009-09-06 11:22:24

  • Eristalis interrupta, mating  1094
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, mating
    DE, Chemnitz, Hutholz; 2009-09-06 11:24:51
    Image number: 1094
    mating
    DE, Chemnitz, Hutholz
    2009-09-06 11:24:51

  • Eristalis interrupta, courtship  496
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, courtship
    DE, Chemnitz, Hutholz; 2008-08-10 11:33:46
    Image number: 496
    courtship
    DE, Chemnitz, Hutholz
    2008-08-10 11:33:46

  • Eristalis interrupta, courtship  932
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, courtship
    DE, Chemnitz, Zeisigwald; 2009-08-15 13:55:16
    Image number: 932
    courtship
    DE, Chemnitz, Zeisigwald
    2009-08-15 13:55:16

  • Eristalis interrupta, courtship  934
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, courtship
    DE, Chemnitz, Hutholz; 2009-08-02 12:20:45
    Image number: 934
    courtship
    DE, Chemnitz, Hutholz
    2009-08-02 12:20:45

  • Eristalis interrupta, courtship  4545
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, courtship, det. thijsdegraaf
    DE, Chemnitz, Harthwald; 2011-05-08 10:34:23
    Image number: 4545
    courtship
    DE, Chemnitz, Harthwald
    2011-05-08 10:34:23
    det. thijsdegraaf
  • Eristalis interrupta, courtship  4544
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, courtship, det. thijsdegraaf
    DE, Chemnitz, Harthwald; 2011-05-08 10:33:21
    Image number: 4544
    courtship
    DE, Chemnitz, Harthwald
    2011-05-08 10:33:21
    det. thijsdegraaf
  • Eristalis interrupta, courtship  4835
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, courtship
    DE, Chemnitz, Hutholz; 2011-08-14 11:56:21
    Image number: 4835
    courtship
    DE, Chemnitz, Hutholz
    2011-08-14 11:56:21

  • Eristalis interrupta, male  4834
    Eristalis interrupta (Poda, 1761)  Mittlere Keilfleckschwebfliege   
    Eristalis interrupta, male
    DE, Chemnitz, Hutholz; 2011-08-14 11:45:36
    Image number: 4834
    male
    DE, Chemnitz, Hutholz
    2011-08-14 11:45:36


Classification:
Eristalis interrupta belongs to the subfamily Eristalinae, tribe Eristalini.
Distribution:
Palearctic (Fennoscandia south to Iberia, the Balkans and Italy, Ireland eastwards through Central Europe into Turkey and Russia and on into the Russian Far East, Siberia and Japan) and Nearctic.
Habitat:
Open forests, parks and other semi-open habitats, rarely in exposed open habitats.
Description:
Eristalis interrupta has a body length of 10 - 13 mm. There is only a small punctiform stigma on the wings and no zigzag band. The face is whitish hairy and has a wide bare black central stripe. In the hind legs, the basitarsus is significantly thicker than the following tarsimeres. The hind femora are usually black, rarely with a yellow base. The front and middle tibiae are at least partially black. In the males, the eyes meet above antennae. The 2nd abdominal segment has distinct yellowish spots, the 3rd segment may be slightly yellow-spotted at the front corners. In the females, the 2nd segment may have distinct yellowish spots. The 3rd segment is unspotted.
There are some similar species.
Biology:
Eristalis interrupta flies in several generations from April to October. The imagines are flower visitors. They are often found on white umbelliferae, yellow composites and many more flowering plants from different families. Some pictures show the conspicuous courtship behavior of the species. Before mating, the males hover over the female for a long time, often several on top of each other. The males are neither aggressive with each other nor against other species. Sometimes they also hover above other flower-visiting insect species.
The larvae of the genus Eristalis belong to the rat tail maggot type. They have a long pull-out breathing tube at the rear end. The larvae develop in streams, ponds, drainage ditches, even in puddles with cow dung. The adult larvae leave the water to pupate in the ground.
Annotation:
Eristalis interrupta (Poda, 1761) = Eristalis nemorum (Linnaeus, 1758)

References, further reading, links:
  1. Pape T. & Thompson F.C. (eds) (2017). Systema Dipterorum (version 2.0, Jan 2011). In: Species 2000 & ITIS Catalogue of Life, 2017 Annual Checklist (Roskov Y., Abucay L., Orrell T., Nicolson D., Bailly N., Kirk P.M., Bourgoin T., DeWalt R.E., Decock W., De Wever A., Nieukerken E. van, Zarucchi J., Penev L., eds.). Digital resource at www.catalogueoflife.org/annual-checklist/2017. Species 2000: Naturalis, Leiden, the Netherlands. ISSN 2405-884X.
  2. M.C.D.Speight: Species Accounts of European Syrphidae (Diptera), Glasgow 2011, Syrph the Net, the database of European Syrphidae, vol. 65, 285 pp., Syrph the Net publications, Dublin.
  3. Gerald Bothe: Bestimmungsschlüssel für die Schwebfliegen (Diptera, Syrphidae) Deutschlands und der Niederlande, DJN, 1984, ISBN 3-923376-07-3
  4. Menno Reemer, Willem Renema, Wouter van Steenis, Theo Zeegers, Aat Barendregt, John T. Smit, Mark P. van Veen, Jeroen van Steenis, Laurens van der Leij: De Nederlandse Zweefvliegen (Diptera: Syrphidae), Nederlandse Fauna 8, 2009.
  5. Speight, M.C.D. & Sarthou, J.-P. (2014) StN keys for the identification of the European species of various genera of Syrphidae (Diptera) 2014 / Clés StN pour la détermination des espèces Européennes de plusieurs genres des Syrphidae (Diptères) 2014. Syrph the Net, the database of European Syrphidae, Vol. 80, 125 pp, Syrph the Net publications, Dublin