Caltha palustris
A wetland species found on tall emergent pond side vegetation, margins of mesotrophic pools and lakes with "Scirpus" or "Sparganium". Flowers visited include "Caltha palustris", "Ranunculus repens", white umbellifers, "Sonchus arvensis", "Sorbus aucuparia" and "Taraxacum". Flies early May to July. The larva is aquatic and microphagous in rotting plant debris. Flies April to October.