Omonadus floralis (Linnaeus, 1758)
Native to southern Asia, this species has been transported worldwide with a wide range of foodstuffs and is now cosmopolitan under artificial conditions, it is the most frequently recorded anthicid among stored products and it has also become established in the wild in many temperate regions. It has been recorded from the wild in most European countries from the Mediterranean to far above the Arctic Circle in Scandinavia and is probably common throughout the region, it is also widespread across North Africa and occurs on all the Atlantic islands. In the UK it is locally common throughout England and Wales and occurs sporadically further north to the Scottish Highlands. Adults are active from March until October and there are records from December and so it is likely they overwinter. Typical habitats are woodland margins, hedgerows, dry grassland and scrub, often on chalky or sandy soils, and they often occur in disturbed areas such as agricultural margins, allotments and gardens, they fly well and visit a range of flowers during the day, often in bright sun, and they sometimes occur in numbers at light late in the evening. Mating occurs in spring and early summer, and the saprophagous larvae develop among decaying plant material, often in well-decayed leaf-litter but also among compost, humus, straw and, sometimes in numbers, among mixed dung and straw. Adults peak in abundance during the spring and again in late summer and so development from egg to adult is likely to be rapid. Under artificial conditions they may be continuously-brooded, depending on conditions; they reproduce readily in the presence of suitable host material and often disperse after a period of feeding and mating. Eggs are laid directly among host material or in crevices in packing material and larvae emerge within a few days, at normal temperatures and humidities they are fully-grown within six weeks will and either construct a chamber from detritus and secretions, or they will pupate exposed among detritus below the host material, the bright-yellow pupae being very distinctive, and adults eclose after a week or so. Adults are long-lived and so after several generations, even allowing for dispersal by flight, very large populations may build up. Cultures have been maintained with various foods mixed with saw dust to provide sites for pupation, but infestations occur in a very wide range of both natural and processed animal and vegetable products including e.g. dried fruit and nuts, seeds of all kinds, dried locusts, sausages, hams, biscuits and cakes, and they are often recorded from food that has started to decay.
Omonadus floralis 1
Omonadus floralis 2
2.5-3.7 mm. The broad head, narrow pronotum and long-oval elytra are distinctive, very variable in colour but usually with the head a darker brown than the pronotum and the elytra pale across the base and substantially darkened in the apical two-thirds, legs brown, usually with darker femora, antennae dark brown with four or five basal segments and the apical half of the terminal segment pale. Head and pronotum finely punctured and pubescent and with very fine linear microsculpture, elytra slightly more strongly punctured less densely pubescent than the pronotum, and without microsculpture. Head transverse with large convex eyes and long, parallel and widely-rounded temples, basal margin almost straight in front of a short and narrow neck, surface weakly convex and slightly depressed medially before the base. Maxillary palpi securiform. Antennae inserted laterally in front of the eyes, 11-segmented and only slightly thickened towards the apex. Pronotum broadest at before rounded anterior angles and strongly narrowed to curved basal margin that appears to have a double border, anterior margin curved, surface weakly convex and with two blunt tubercles behind the anterior margin. Elytra elongate, broadest behind the middle and evenly curved from rounded shoulders to separately curved apical margins, without striae but sometimes with a fine line near the suture in the apical half, in most specimens evenly convex but sometimes weakly depressed in the anterior third. Legs long and slender, femora simple, tibiae only weakly expanded from the base, each with a fine apical spur on the inner margin. Tarsi 5-5-4, the penultimate segment bilobed, basal segments of front tarsi broadly expanded, those of the middle tarsi less strongly so, and those of the hind tarsi long and slender. Claws smooth and without a distinct basal tooth.