Sun, 28/04/2013

Carabus arvensis is a widespread Palearctic species, that shows a lot of beautiful colour variations. Sometimes three different colour morphs can even be found in the same area. The most common and widespread colour morph found in Western Euope is 'coppery bronze'. During Eastern Holidays, I went to Senonches, in France, for some specificic colour morphs. In Senonches there is a dominance of blackish and purple colour morphs.

Under here, the blackish and purple colour morphs from Senonches.

 

Under here, the classic coppery colour morph, which I photographed in the surroundings of the Forêt de Coucy-Basse, in Northern France.

Under here, a rather rare colour morph found in Limburg, Belgium. The ground beetle has vivid green elytra and a reddish coppery thorax.

They all belong to the Carabus arvensis, subspecies sylvaticus. The greenish colour morph on the last picture is named by the carabologists Carabus arvensis sylvaticus f.i. bicolor.

The species must have been once widespread in the Netherlands and in the large heath areas in Belgium, but in these regions the species has become increasingly rare, mainly due to habitat loss. Carabus arvensis is still found in some wet and boggy heath areas, but is nowadays very patchily distributed. Same goes for it's distribution in France and the Ardennes in Belgium, where the species can be locally abundant, but seems to vanish a few kilometers further in a same forest area. In the Ardennes it shows a preference for forests on calcareous soils, where it is often found on sunny places such as clearcuts. In France I found the species in rather acid and wet forests.