Seitz describes it "Male above shining violet blue, only the apical portion of the costal margin being minutely edged with white.

On Ivy, Ilex, Euonymus, Rhamnus, Robinia, Genista, Spartium, Astragalus, Rubus, Erica, Pyrus and many other plants; in Europe visited usually by ants of the genus Lasius; in June and the autumn.

In their monograph on the Lycaenopsis group of polyommatine genera, Eliot & Kawazoe, 1983, list 14 taxa as valid subspecies names, plus many further synonyms to which they accord lesser status.

According to Eliot & Kawazoe, 1983, these 14 subspecies are divided into four groups as follows: Palaearctic & North African South and South-East Asian Far Eastern

[6] The holly blue is subject to marked population cycles which appear to be caused by interactions with the parasitoid ichneumon wasp Listrodromus nycthemerus.