Large Copper

Lycaena dispar is a large lycaenid butterfly with a wingspan of 44–52 mm. The species exhibits strong sexual dimorphism. Males have bright orange wings with narrow black margins and white fringes. The short androconia (sex brands) are located near the leading edge of the forewing. Females have broader dark brown margins on the forewings with a parallel row of dark spots. Both sexes have distinctive silvery-blue hindwing undersides patterned with black spots and an orange submarginal band. This silvery underside distinguishes L. dispar from related species such as Lycaena virgaureae and L. hippothoe, which inhabit drier environments. The subspecies can be differentiated by size, extent of black markings, and the length of the orange band on the hindwing underside. The extinct English subspecies (L. d. dispar) was notably variable in size and had larger spots on the underside than continental European forms.

Lycaena dispar occurs between latitudes 40° and 60° across Eurasia. The species is currently found in: Armenia, Austria, Azerbaijan, Belarus, Belgium, Bulgaria, China, Croatia, Czech Republic, Estonia, Finland, France, Georgia, Germany, Greece, Hungary, Italy, Kazakhstan, Republic of Korea, Latvia, Lithuania, Luxembourg, Moldova, Mongolia, Montenegro, Netherlands, Poland, Russian Federation, Serbia, Slovakia, Slovenia, Switzerland, Türkiye, Ukraine and Uzbekistan. The species shows contrasting population trends across its range: severe decline in north-western Europe, stability or expansion in central and northern Europe, and mixed status in Asia.

Most European populations are bivoltine with two generations annually: May–June and late July–early September, with peak flight in July. Northern populations (e.g. Estonia) are univoltine, while southern populations may produce a partial third generation. The species overwinters as half-grown third-instar larvae, which enter diapause triggered by temperatures below 15°C and photoperiod cues. Larvae resume feeding in early May when temperatures exceed 25°C. Heavy mortality occurs during the overwintering period, particularly from prolonged flooding.