Habitat preferences and seasonal activity of Agonum mannerheimii (Coleoptera, Carabidae) in a Swedish spruce bog

The seasonal activity of a local population of Agonum mannerheimii (Dejean) in a spruce bog was investigated with pitfall traps in 1989. From April to November 330 specimens of A. mannerheimii and 622 beetles of 17 other species of Carabidae were caught. The activity abundance of A. mannerheimii peaked in early spring, and in late summer and autumn no specimens were caught. The main cause for this absence was probably drought. Pterostichus nigrita (Paykull) (inclusive of P. rhaeticus (Heer)) was seemingly not influenced in the same way. The collecting of A. mannerheimii in different habitats indicates that it is not the habitat specialist as previously suggested. It is probably overlooked in Swedish forests.