Meligethes aeneus is the most common species of Pollen beetle in the UK. It is quite a small beetle, around 1.5mm-2.5mm long. They have a black cuticle with a metallic green-blue shine, and club shaped antennae.
Feeding on pollen, Meligethes species generally don't cause harm to plants, however they can sometimes damage buds by chewing into them in search for pollen. This damage can cause the buds to die, and so the beetle is considered a pest, particularly by farmers of oil-seed rape, where they can be quite damaging.
Although they do little damage to plants already flowering, Meligethes aeneus may also be considered a pest by gardeners, mainly due to the large numbers it appears in, akin to an infestation.