Male, Switzerland, July 2016, in habitat with alpenrose and Vaccinum
Male, Switzerland, July 2017
Male, Switzerland, August 2014
Male, Switzerland, August 2014
Female, Switzerland, July 2018
Male, Switzerland, July 2014
Male, Switzerland, August
2014
Female, Switzerland, June 2010
Female, Switzerland, August 2013
Switzerland, August 2014
Male, Switzerland, July 2009
Male, Switzerland, July 2009
Female, Switzerland, July 2006
Male, Switzerland, July 2006
Male, Switzerland, July 2008
Female, Switzerland, July 2007
Female, Switzerland, July 2007
Female, Switzerland, July 2006
Female, Switzerland, July 2006
Female Switzerland, July 2006
Distribution
This beautiful little blue is associated in my part of Switzerland with
upland areas covered in Vaccinium(bilberries
and related species), its
foodplant, and spends most of its time in close proximity to these
plants. Elsewhere, especially in the north, it can be found in bogs and
moorland at lower altitude, though always in association with the
foodplant. Its range extends through the boreal regions into Alaska and
Canada. In Switzerland it commonly flies with moorland clouded yellows
and cranberry fritillaries, though less frequently with the latter as
this is a less common butterfly.
From
the upperside the male is a deeper purple than many other blues -
certainly, deeper than the related Plebejus
species
- and this is visible even in flight. The female is rather
leaden in appearance, though she may have some blue on her. But it is
the underside that really gives the game away with this butterfly. The
orange lunule in space 3 of the hindwing is swollen and the black spot
outside it contains a gleaming, gem-like, blue centre. The adjacent
lunules may show some orange, and that in the anal angle some blue, but
otherwise the submarginal region is black on grey. The whole
appearance is quite unmistakable and like nothing else in Europe.
The butterfly flies from late June (more normally July in my part of
Switzerland) through to August. Eggs are laid on leaves or stems of the
foodplant and hatch the same year but the caterpillars hibernate while
young, feeding up on the fresh leaves when they emerge from the snow
the following spring.