Phylum Arthropoda (Arthropods) ➔ Subphylum Crustacea (Crustaceans) ➔ Class Malacostraca (Malacostracans) ➔ Order Isopoda (Pillbugs, sowbugs, woodlice) ➔ Family Oniscidae

Oniscus asellus Linnaeus, 1758

Mauerassel Common Woodlouse

Synonyms and other combinations:

Oniscus affinis Say, 1818 | Oniscus fossor C. Koch, 1838 | Oniscus lamperti L. Koch, 1901 | Oniscus languidus L. Koch, 1901 | Oniscus murarius Cuvier, 1792 | Oniscus nodulosus Verhoeff, 1934 | Oniscus vicarius Stuxberg, 1872 | Porcellio lineatus Fitch, 1855 | Porcellio taeniola C. Koch, 1835 |

  • Oniscus asellus 6121
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus
    DE, Chemnitz, Hutholz; 2013-06-17 13:55:58
    Image number: 6121

    DE, Chemnitz, Hutholz
    2013-06-17 13:55:58
  • Oniscus asellus 5962
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus, det. Jürgen Peters
    DE, Chemnitz, Harthwald; 2013-04-25 15:03:23
    Image number: 5962

    DE, Chemnitz, Harthwald
    2013-04-25 15:03:23
    det. Jürgen Peters
  • Oniscus asellus, bottom view 5963
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus, bottom view
    DE, Chemnitz, Harthwald; 2013-04-25 15:02:00
    Image number: 5963
    bottom view
    DE, Chemnitz, Harthwald
    2013-04-25 15:02:00
  • Oniscus asellus 6191
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus, det. Jürgen Peters
    DE, Chemnitz, Zeisigwald; 2013-07-08 14:08:04
    Image number: 6191

    DE, Chemnitz, Zeisigwald
    2013-07-08 14:08:04
    det. Jürgen Peters
  • Oniscus asellus 9821
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus
    DE, Chemnitz, Harthwald; 2020-06-17 13:55:19
    Image number: 9821

    DE, Chemnitz, Harthwald
    2020-06-17 13:55:19
  • Oniscus asellus 9817
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus
    DE, Chemnitz, Markersdorf; 2020-11-01 12:25:21
    Image number: 9817

    DE, Chemnitz, Markersdorf
    2020-11-01 12:25:21
  • Oniscus asellus 9818
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus
    DE, Chemnitz, Markersdorf; 2020-11-01 12:26:25
    Image number: 9818

    DE, Chemnitz, Markersdorf
    2020-11-01 12:26:25
  • Oniscus asellus 9819
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus
    DE, Chemnitz, Markersdorf; 2020-11-01 12:34:36
    Image number: 9819

    DE, Chemnitz, Markersdorf
    2020-11-01 12:34:36
  • Oniscus asellus 9820
    Oniscus asellus Linnaeus, 1758  Mauerassel  Common Woodlouse 
    Oniscus asellus
    DE, Chemnitz, Markersdorf; 2020-11-01 12:34:43
    Image number: 9820

    DE, Chemnitz, Markersdorf
    2020-11-01 12:34:43

Distribution:
Europe (except the Mediterranean); North America; Dominican Republic; North Atlantic Ocean; South Atlantic Ocean.
Habitat:
Damp forests, often in the human settlement area.
Description:
Size: (15-18) mm x (6-10) mm; body: broad, strongly flattened, surface clearly grained, shiny, dark brown with variable spots; antenna with tripartite flagellum; frontal edge of the head in front of the eyes on both sides with long protruding frontal lobes.
Biology:
The Common Woodlouse Oniscus asellus prefers damp and dark places. The species has a low resistance to dehydration. In forests it is often found under stones, the loose bark of rotten tree stumps and under deadwood. Oniscus asellus hides during the day and comes out after dark. The predominantly nocturnal activity is caused by light sensitivity, lower nighttime temperatures and relatively high humidity.
Common woodlice feed mainly on fallen leaves, white-rotted wood and rotting plant parts.

References, further reading, links:
  1. Boyko C.B, Bruce N.L., Merrin K. L., Ota Y., Poore G.C.B., Taiti S., Schotte M. & Wilson G.D.F. (Eds) (2008 onwards). (2018). WoRMS Isopoda: World Marine, Freshwater and Terrestrial Isopod Crustaceans database (version 2017-03-01). 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. Bellmann, Heiko: Kosmos-Atlas Spinnentiere Europas, Franckh Kosmos Verlag-GmbH & Co., Stuttgart, 3. Auflage von 2006, ISBN 3-440-07025-5