I first saw a single male in the Queyras National Park in 2000, and then another at Isola in 2002. However, in 2003 at the Col de Lauteret near Briançon I saw another, then another and then realised that they could be counted in hundreds if not thousands. I have since seen damon in huge numbers at several high altitude locations. Both sexes have the very strong white unh streak which is characteristic of this species and it could only be confused (in France) with the Ripart's Anomalous Blue (P. ripartii).

The undersides are very similar, the unh of ripartii having heavier and more extensive black spots, extending into s1 and s2, but the main and probably constant differentiating factor seems to be that the margins of damon are white, but brown for ripartii. The underside of the female Furry Blue (P. dolus) of the subspecies vittatus is very similar but paler in colour. The female dolus I have seen have been of the nominate form not vittatus, so my experience is limited here.

Damon is slightly unusual in that the underside ground colour is often brown in the male as well as the female, whereas for most blues the male is grey (or greyer) than the usually-brown female. However, as shown above, the male upperside is strongly blue and the female brown. The male upperside could possibly be confused with the Amanda's Blue (P. amandus) in terms of the dark borders, although damon is rather darker and smaller than amandus and the undersides are completely different.

This species was previously known as Agrodiaetus damon.

observations

showing the characteristic dark borders which extend along the uph veins.

a typical male.

a typical female, plain brown and unmarked, with bluish suffusion on the thorax hairs and in the basal region.

a rather worn female, showing a smattering of basal blue scales. It is on the larval hostplant Sainfoin (Onobrychis viciifolia).

a male, a fairly normal colouring in that the unf ground colour is rather greyish compared to the unh.

a male, quite deep rich chestnut brown. Whether this is a geographical or an altitude effect of both 17862 and 22584, given that they were both seen in Isère and at very low altitudes for this species, is unclear. The colouring is certainly unusual. I am assuming that the fact that they are (or appear to be) taking salts indicates that both are males, but it is possible that they are females just taking moisture.

a male, a lighter brown than 17862.

a typical female underside, quite a strong clean brown on both wings.