Ground Beetles of Ireland

Chlaenius nigricornis

Click on the image to enlarge it in a new window
Chlaenius nigricornis
© Roy Anderson
Chlaenius nigricornis
Click on map to enlarge it in a new window
(Maps updated 30th November 2009)

Chlaenius nigricornis (Fabricius, 1787)

Description: A pubescent, moderate-sized (10-12.5mm) metallic copper and green ground beetle found in marshes and reedbeds. Mainly on limestone, southern and western.

World Distribution: A Eurosiberian Wide-temperate species (64) distributed from western and northern Europe to eastern Siberia.

Irish Status: Johnson & Halbert (1902) regarded this species as common on riverbanks and lakeshores throughout Ireland, and included "Antrim (Rathlin to Belfast), Down, Armagh, Fermanagh" within its range. Today it is restricted mainly to Fermanagh in the northern counties and, though widespread, is possibly less common than formerly in southern counties also.

Ecology: Largely riparian on the margins of eutrophic lakes and sluggish rivers in Ireland, and nowadays mainly in limestone areas of the west. Sometimes encountered running on open ground in bright sunshine.

Remarks: It appears to be declining over most of the northern parts of its European range. In Britain and Ireland there has been a substantial decline in eastern areas. This is a curious and unusual pattern and suggests a linkage with the increasing acidification of soils from both industrial and agricultural sources.