Host plants:
The larvae are possibly polyphagous, but prefer Fabaceae. I recorded them in a Lotus pad at a sparsely vegetated place near the coast on the peninsula São Lourenço (Madeira, March 2013).
Habitat:
Idaea atlantica should occur in various habitats from the coast to gardens and parks, but preferably in lower altitudes.
Life cycle:
The moths are likely to occur year-round. The larvae have been concealed in the inner parts of the dense Lotus pads during daytime.
Remarks:
Idaea atlantica is endemic to Madeira (Portugal).