Ophonus azureus (Fabricius, 1775)
Suborder:
Family:
Subfamily:
Tribe:
Genus:
ADEPHAGA Clairville, 1806
HARPALINI Bonelli, 1810
Ophonus Dejean, 1821
This very widespread Western Palaearctic species occurs throughout Europe from Spain to Greece in the south and to the UK and a few southern provinces of Fennoscandia to the north, it is present on most of the Mediterranean islands and is widespread in North Africa and Asia Minor. To the east it extends into Central Russia and Turkestan and it is known from Syria and Iran. The species is thermophilic and typical of lowlands and south-facing hillsides although in Central Europe it occurs in low mountain meadow up to 1500 m., throughout Southern Europe it is locally common and often abundant but it becomes much more local and scarce in the north where there seems to have been a general decline since the middle of the twentieth century. In the UK it is very local and generally scarce across England north to the Wash and there are a few, mostly coastal, records from the West Country, Wales and further north to Cumbria, again there seems to have been a general decline and many of our records are from before 1970. Typical habitats are light calcareous or stony soils with patchy and rather open vegetation, often on agricultural borders and ruderal sites. Adults are mostly nocturnal, spending the day under stones or matted vegetation etc, but they are sometimes active on the ground or may climb grass stems etc in hot weather. Breeding occurs mostly in the spring with larvae developing through the spring and summer to produce new-generation adults that will go on to overwinter, but teneral adults have also been recorded in June, which suggests that at least some adults will reproduce in the autumn. In the UK adults occur year round and peak in abundance during May and June. Both adults and larvae are primarily phytophagous, feeding mostly on seeds, the adults often climbing stems to do so, and the larvae feeding on the ground or, typical of many members of the genus, storing seeds in burrows and feeding underground. Both fully-winged and brachypterus forms occur in the UK. Adults may be found under debris by day but sweeping or searching by night is probably the best way to find them.
Ophonus azureus 1 |
---|
7-8.5 mm. Body metallic blue, sometimes with the forebody a little darker, antennae, legs and pronotal margins pale brown, occasional dark brown and non-metallic specimens (var. similis) occur. Pronotum and elytra with fine pale pubescence. Head proportionally large, the prominent convex eyes and converging temples, surface smooth behind the eyes and moderately strongly but not densely punctured across the vertex and frons, frons with a single setiferous puncture beside each eye. Maxillary palpomeres long and slender. Antennae densely pubescent from the third segment. Pronotum transverse, broadest in front of the middle and very slightly sinuate before obtuse and rounded posterior angles, surface strongly punctured and with wide and shallow basal fovea, basal margin distinctly bordered. Elytra evenly curved from rounded and finely toothed shoulders to a rounded apical margin, the subapical constriction at most very weak, basal margin evenly curved, striae narrow and complete to the apex, interstices finely and rather densely punctured, these sometimes joining the striae so that they appear punctured in places. Front and middle tarsi dilated in males. Distinguished among our UK species by the small size and the form of the pronotum.