Micropterix calthella

Micropterix calthella, the marsh marigold moth, is a species of moth belonging to the family Micropterigidae. It is found in damp habitats throughout Europe (except for the far south) and is also distributed eastwards to central Siberia.

This rather small moth has a forewing length of up to 4.6 millimetres (0.18 in) and a wingspan of 8–10 millimetres (0.31–0.39 in). This is one of the more plainly marked Micropterix species of Europe, with rather dark bronze-coloured forewings with distinctive purple bases. Like other members of the family, this species has functional jaws and it feeds as an adult on pollen grains from a wide variety of plants such as Acer, Ajuga, Caltha, Cardamine, Carex, Crataegus, Mercurialis and Ranunculus.