Holly Blue Butterfly Egg.

The egg of a Holly Blue Butterfly. I noticed a female Holly Blue butterfly taking a lot of interest in a Hypericum bush in my garden, she would alight on the flower buds and carefully select a safe position to deposit her egg, a single one on each flower bud before moving on to the next. I have never before seen or heard of the Holly Blue ovipositing on Hypericum, a new foodplant perhaps?