Alexis is a widespread and quite common early season butterfly, emerging in late April but having largely disappeared in Var by the time July arrives. The underside markings vary quite dramatically; the unh spots can be almost non-existent and the strong unf spots greatly reduced (the books describe this as "variant"), when the female could almost be confused with the Mazarine Blue (Cyaniris semiargus) if the forewing is tucked below the hindwing. The underside colour, as can be seen from these photos, is also highly variable, and one could be forgiven for thinking that these alexis shots were of several different species. Only occasionally is a female greenish in colour, with a greenish basal sheen, so this species is probably mis-named.

The male upperside has a conspicuous wide black border, widening at the apex; this serves to differentiate the male alexis from any other species in France. The blue colour is quite strong and slightly darker than the Common Blue (Polyommatus icarus), which it resembles in terms of size. The female can vary from almost completely brown to having extensive blue in the basal areas of both forewings.

Black-eyed Blue (G. melanops) is very similar, the main distinguishing feature being the grey marks around the underside margins of both wings. These can vary between just discernible, to quite strong in melanops, so sometimes a good view is needed to confirm their existence. Alexis has no marginal markings, even vestigial, so this is a definitive ID clue. Melanops is often smaller in size, and the male upperside has, in my opinion, a rather paler steely-blue colouring, although at least one expert does not concur. The melanops black border is not dissimilar to the alexis border but is not quite as neat and tidy.

observations

the characteristic black borders widen toward the apex.

perhaps with rather more blue scales than usual.

very limited blue scales in the basal area.

only two or three very vestigial unh spots, unusual but it does happen from time to time. The angle of the shot suggest it has developed a wiggly tail.

I am really uncertain about this. I feel that the wing shape is good for alexis, and alexis is known to be highly variable in its underside spots, although normally it is the unh spots that are missing, rarely the unf. One expert has expressed the view that it is not alexis.

slightly browner underside than most females.

a mating pair, female below. The male seems fairly normal, albeit with only three smallish unh post-discal spots, but the female is clearly green with a strong basal green flush, and a series of five small unh post-discal spots. I have never seen any alexis to be this clearly green.

another mating pair, although here they are more similar. I suspect the female is above as it has a greenish tinge whereas the lower butterfly is bluer and maybe therefore more likely to be male.