Whilst searching for Chalkhill Blues in southern Lithuania on 30 July, I discovered a female Meleager's Blue (Meleageria daphnis) taking nectar from Tansy (Tanacetum vulgare) flowers. This constitutes for the first record of the species in Lithuania and the Baltic States. Remarkably, I found a second individual a week later at a distance of 550 metres from the first, this second being a male.

The site, located less than a hundred metres from the Belarus border south-west of Druskininkai, was an area of mixed meadows and pine forest, largely on sandy soils. Active and mobile, the butterfly was watched for about fifteen minutes as it moved rapidly from flower clump to flower clump, the habitat being an abandoned meadow rich in flowers and over growing with raspberries, assorted mixed shrubs, bushes and occasional pines in places.

Sexually dimorphic, the female is the more distinctive of the species, the pronounced scalloping to the rear hindwings making it unique amongst European Lycaenidae. Other distinctive features of this individual included the rear underwing pattern, specifically pale crescents and scallops mirroring the wing shape on a generally pale background colour, plus a pale streak running through the centre of the rear wing from near the outer margin to to the fiscal area. No spot in the cell of the forward underwing. Upper wings were dark brown, again with pale crescents and scallops mirroring the shape of the rear wing. The individual was photographed, showing both the underwing and upper wing.

With a European distribution range stretching from southern Europe through to Ukraine and the Balkans, the closest known populations of Meleager's Blue are in southern and eastern Poland, northern Ukraine and parts of Belarus. As a non-migratory species, its occurrence in Lithuania is quite remarkable, opening the possibility that unknown populations exist between this locality and the known range in Belarus or Poland.

Incredibly I found a second individual on 6 August - a male about 550 metres from the female location (which I failed to locate again). A far less distinctive butterfly than the female, the rear scalloping is very much reduced and can almost be overlooked in the field. Likewise, the marking on the underwings are less distinctive, the basic pattern being a shadow of that of the female.

Despite never having been recorded in Lithuania, the presence of two individuals in close proximity strengthens the possibility that a small population of this non-migrant does actually exist in the immediate area. This can also be considered likely as the food plants of the caterpillar, Crown Vetch (Coronilla varia) and Wild Thyme (Thymus serpyllum), do occur in southern Lithuania, thus potential certainly exists that further records may occur, though the complicated life cycle of the species also requires the presence of ant species (genera Lasius, Formica or Tapinoma) to tend the larvae.

As a side note, simultaneous with the discovery of this Meleager's Blue in Lithuania, another butterfly of largely southern distribution, namely Marbled White (Melanargia galathea) was present in exceptional numbers in the same general area. Prior to 2016, the only records of this species in Lithuania were in 1921 and 1926 (three individuals in Panevėžys) and 2001 (one individual in Viešvilė). In 2016, representing an unprecedented influx in the border area south-west of Druskininkai, I found an absolute minimum of 58 individuals between 23-30 July at three sites in close proximity, with a further single 30 km north-east near Margionys. Students also found further individuals at a distance of approximately 10 km from Margionys.

With the acceptance of Meleager's Blue, I believe the Lithuanian butterfly list stands at 127 species. Eight further species are noted in Butterflies of Lithuania (Povilas Ivinskis & Jonas Augustauskas, 2004) as possible contenders to be recorded in the future, though Meleager's Blue was not among these.