Wednesday, July 20, 2011

A Darkling Beetle, Lagria hirta

Lagria hirta
A conspicuous little beetle, with an abdomen that looks all the world like a miniature kiwi fruit, Lagria hirta is most commonly found in sandy places in Ireland, but can be found throughout the country. While the larvae eat detritus, the adults can be found feeding on a variety of flowers such as umbellifers and Compositae (1). L. hirta has a univoltine life cycle, that is it produces just one brood per year. Adults are present for only a short time in summer, whereas the larval stage extends from autumn to spring (2). This adherence to univoltism has been shown to be due in part to larval diapause (or dormancy) (3). It was shown under laboratory conditions that larvae did not pupate if kept at constant temperature. Pupation was only achieved if larvae were reared at 15-20°C, followed by a three moth chilling period of 5°C.
Lagria hirta

References:
  1. Joy, 1932,  A practical handbook of British beetles
  2. Zhou, 2001. Environmental Entomology 30 pp. 686-691(6)
  3. Zzhou and Topp, 2000. Entomologia Experimentalis et Applicata 94 pp. 201–210

No comments:

Post a Comment