This is a green colour morph of Elaphrus uliginosus. In the North and the East of Europe the beetles are darker coppery-brownish or blackish coloulerd, often coloured like Elaphrus cupreus. Unlike elaphrus cupreus who has only blue tarsi, its legs are entirely blue coloured, including the blue shins. The relief around the blue dots is less explicit then in Elepahrus cupreus, but still present. Elaphrus riparius, which is also green coloured, has no relief around the blue dots and has green legs.
This ground beetle is becoming increasingly rare in Western Europe, due to the intensivation of agriculture, which leaves no place for very wet, peaty and nutrient poor meadows. Unlike it's mentioned two relatives it is an ambush hunter who stalks it's prey from well covered vegetation. It hunts during day-time in dense moist grasslands which have at most 20 -30 % bare soil. Elaphrus cupreus and especially riparius require both more open banks of rivers and lakes, with bare soil.