Zabrus tenebrioides (Goeze, 1777)

This is a common and often abundant species throughout Europe from Spain to Western Russia, Ukraine and Kazakhstan, extending north to Denmark and Southern Scandinavia and south to North Africa and Asia Minor. In the U.K. it is a very local species of central and southern England with many records from coastal areas of Dorset, Hampshire and Sussex, and there is a single record from South Wales. The typical habitat, or at least the habitat where it might attract attention, is agricultural land used to grow wheat, barley and, occasionally, oats. They are rarely little more than a nuisance but on the continent, at least up to the middle of the 20th century when agricultural practices and the use of treated seeds helped to control the species, it was occasionally a serious crop pest, being responsible for stripping areas of fields down to bare soil. New generation adults appear from early summer and climb stems at night in order to feed upon seeds for a while before dispersing by flight for short distance over crops, they continue feeding nocturnally through the summer although during the warmest periods they burrow down to about 40cm in the soil and remain inactive until the temperature falls later in the summer when they resume feeding once more. They mate from early summer and oviposition begins in June or July, although generally a little later in the U.K.; females deposit small batches of 3-5 eggs in depressions or burrows in soft soil, and each will lay up to 250 eggs. Larvae emerge between 1-3 weeks later and begin feeding nocturnally on leaves, climbing stems to do so, as they grow they burrow down as far as 40cm into the soil and pull in leaves so that they can continue feeding during the day. An indication of the presence of larvae is skeletonised leaves around the bases of stems in discreet feeding areas although when present in numbers these areas are extensive and completely stripped plants are usually present. They continue feeding until the onset of cold weather when they retreat into the burrows to overwinter, occasionally feeding during mild spells, and resume feeding in the spring. Pupation occurs in an underground cocoon in the spring, generally late April to Late May, and adults eclose after 2 or 3 weeks. The adults will damage seed heads from the onset of flowering to when they are fully mature and they are often completely destroyed, the beetles move quickly between plants through the summer and they are long-lived, often overwintering in the soil beneath the host plants.