A female Melissa Blue (Plebejus melissa) basks on the sand in Dinosaur Provincial Park, Alberta. All blues are sexually dimorphic, with the males having a bluish dorsal wing surface and the females brown. This female has a sprinkling of blue on the thorax and wings, hinting at its (subfamily) Polyommatinae heritage. Melissa Blues range in mostly prairie habitats in Alberta, with the caterpillars feeding on plants such as lupines, vetch, alfalfa and loco-weed. Melissa Blue larvae produce a sweet secretion that attracts ants, allowing them to form a symbiotic relationship that helps protect them as they grow. Larvae overwinter, and the main flight time for adults is from mid-May to mid-September.
(Canon 5D Mark II, 100mm macro lens on Kenko Pro 1.4x teleconverter. ISO 200, 1/200 sec. @ f22. Fill flash.)