A dandelion crammed with tiny bronze-black beetles. Our favourite entomologist emailed us:
They’re pollen beetles. Getting a positive ID is going to be impossible without sending me a specimen (and they’re too small!) but this time of year the most common species is the Common Pollen Beetle Meligethes aeneus.
Common pollen beetles overwinter as adults in sheltered places and emerge in the early spring. They are attracted in large numbers to yellow things : daffodils, dandelions and oilseed rape, tennis balls and hi-viz vests with Friends of Southwick Country Park written on the back.
They are important spring pollinators, feeding mainly on pollen and nectar. The females lay their eggs inside the flower buds of various species of Brassica and their larvae, when they hatch, feed inside the flower buds on its stamens and pistil; the damaged flower is no longer able to make seed and dies, which makes common pollen beetles an agricultural pest in the eyes of farmers trying to grow oilseed rape.
When the larvae have finished feeding, they go into the soil to pupate. The adult beetles emerge in July and August and seek out flowers where they feed on pollen and nectar until it is time to find a sheltered place to hibernate.
A small and fascinating piece of the park’s wildlife, happening almost invisibly inside one of our most common flowers.
Another of the park’s Coleoptera: