Hypera meles (Fabricius, 1792)

This is a common and very widespread Palaearctic species, it occurs throughout Europe and Mediterranean North Africa, the Middle East and Asia Minor, extending north to the UK and reaching the Arctic Circle in Fennoscandia, to the east it is widespread through southern Asia and Siberia. It was first recorded in the United States from New York in 1907 and is now established, though sporadically, in various eastern and central states and it has become established in Canada since being first recorded in 1951. Here it is locally common in England north to south Yorkshire, it was formerly considered as rare but there seems to have been a recent increase in abundance. Adults overwinter in the soil and become active during warm days in April, after a period of feeding they mate on stems and leaves of host plants, mostly meadow clover, Trifolium pratense L. and white clover, T. repens L. but also other species of clover as well as lucerne, Medicago sativa L., yellow lucerne, M. falcate L. and birds-foot trefoil, Lotus corniculatus L. They are likely to occur wherever the host is common; grassland, agricultural land, hedgerows and roadsides etc. and because the hosts are quick to colonize new areas they often occur on ruderal sites. Oviposition occurs soon after the weevils appear; females chew small depressions in fresh leaves and insert a single egg or a small group of eggs and larvae emerge within a week or two but the percentage of eggs hatching as well as the time taken for larval development is strongly influenced by temperature and therefore the season. Larvae feed externally on the foliage and are conspicuous; dull green with a broad creamy band along the dorsal surface and resembling small lepidopteran larvae, they pass through four instars and are fully grown by June or July, depending on the season, they now construct a net-like cocoon among the foliage in which to pupate and this entire cycle from egg to adult takes between six to ten weeks at northern temperate latitudes. New generation adults contribute to a peak in abundance during mid-summer but during the warmest times they enter the soil to aestivate and become active again for a while during September and October before entering the soil to overwinter. Adults may be sampled by sweeping the host plants but they generally occur in small numbers or singly, larvae and pupae need to be looked for very carefully, they are not difficult to spot but will need to be reared to adults to confirm their identity. Curiously we once found several cocoons (on Croxley Common Moor) on clover that contained eclosed and perfectly formed but dead adults.