Host plants:
The larva feeds on Clematis species, especially Clematis vitalba. But there are also hints on Pulsatilla. I observed a freshly emerged female in a Pulsatilla-rich limestone grassland without Clematis in the Upper Danube Valley near Beuron in May 2013.
Habitat:
Horisme vitalbata inhabits all more warm Clematis sites from riparian forests to hedges. Additionally it may settle in grasslands with Pulsatilla.
Life cycle:
The pupa hibernates and the moths occur in most often two generations between April and August or even September. The larvae live between May and October.
Remarks:
Horisme vitalbata is widely distributed in Europe with exception of the Far North and also occurs in temperate Asia.