Life history of Amara fulva (Coleoptera: Carabidae) in the southwest forest zone of the East European Plain

Abstract

The patterns of seasonal activity, sex and age structure, reproductive characteristics and overwintering distribution of Amara fulva were studied in the southwest forest zone of the East European plain. A total of 1212 adults (664 males and 548 females) and 38 larvae were collected using pitfall traps. All adults were dissected to determine their reproductive condition. 185 larvae and 5 adults were collected by sampling soil. Adults of A. fulva were active from the first half of June until October with a single peak of activity in August. From June only postgenerative and newly emerged beetles were caught in traps. Immature and mature adults were recorded from the second half of July. At the end of August, more than 90% of the population was represented made up of mature adults. Immature individuals were trapped up until October after which they overwintered. Oviposition period lasted 11 weeks (from the mid-July to the end of September). Maximum number of mature eggs in ovaries was recorded in the second half of August. Larvae of A. fulva were caught from the second half of August to October and the peak in their subsoil activity was recorded in the first half of September. The life cycle of A. fulva is described as facultatively-biennial. Overwintering larvae and adults occurred in different parts of the floodplain. Larvae preferred to overwinter in soil under Persicaria maculosa near the edge of a river, while adults overwintered far from water and, rarely under tussock grasses on sandbars. The larvae of A. fulva cache the seeds of P. maculosa. Rearing A. fulva under field conditions revealed that this species takes 254-328 days complete its development, which includes the winter period.