A species of the higher ranges of the Alpes and Pyrénées. The male upperside is a shining pale blue with strong uneven uph black borders sometimes as detached black spots in each space, and with slight chequering of the fringes. These males above from different locations look very different, though. T&L shows it as being very pale and with a medium but constant width upf black border. You would have difficulty ID'ing these photos from the T&L illustrations. The underside is very similar to the Common Blue (P. icarus) even to the extent of having a unf cell spot, which many icarus-similar blues do not have. The ground colour is usually a cold clean mid-grey.

In 2010 I found eros at a number of locations, always males and nearly always puddling. Only at one location did I see them in good numbers. I have only twice seen a female eros.

observations

a male, with a black upf border of neatly consistent width and a uph border just about breaking up into discrete black spots. It has a Safflower Skipper (Pyrgus carthami) for company.

a male, rather darker blue and with a narrow upf border extending internally along the veins.

a male, not unlike 22088 but rather lighter in colour, with a Glandon Blue (Agriades glandon) for company.

a male, closer to the T&L illustration, with very pale blue near the uph margins, where the black border is decidedly spotted.

a rarely-seen female, only ID'd for certain because I had seen the underside.

a male, typically grey and with rather heavy internal edging to the unf marginal lunules.

a male, very aesthetically pleasing pale grey ground colour, nicely and cleanly marked.

a male underside, very similar to icarus, but more lightly marked at the margins.

a male underside, slightly browner than 13217 but still quite a "cold" grey.