Full scientific name:
Polyommatus thersites (Cantener, 1835)
Flight Period and Life Cycle
2 broods per year. Overwinters as caterpillar.
Distribution in Croatia
Common in the coastal area. Check the included map.
External Morphology Characteristics
The upper side of wings is blue in males and brown in females. Males have blue gradual darkening in discal and postdiscal zones on the upper side of the forewing. This is andriconal zone. In females, the series of dark and orange spots are more prominent on both wings. The cell spot is missing. Similar to Polyommatus icarus form icarinus and Polyommatus escheri. The comparison is below:
(1) Orange spot in S7 is more prominent in Polyommatus thersites and very weak in Polyommatus escheri.
(2) In Polyommatus thersites in zones from S2 to S4, the orange spots barely touch margin black spot, and touch is absent in S5 and S6. In Polyommatus icarus form icarinus there is a noticeable stronger touch in S2 and S3. The touch weakens in S4 and S5 and there is no touch in the S6. In Polyommatus escheri, the touch is weak on S4 and almost absent on S6.
(3) The black elongated spot in the discal zone is weakly expressed in Polyommatus thersites. It is a bit more prominent in Polyommatus icarus form icarinus. In Polyommatus escheri, it is clearly marked and has sharp edges.
(4) Black spots in zones S5, S6 and S7 are placed on a slightly curved imaginary line. The imaginary line is marked in pink color. In Polyommatus thersites, that imaginary line is a little more rounded, i.e. a black discal spot in zone S6 is closer to the orange spot in zone S7.
Imago feeds with nectar of various flowers.
Caterpillar Host Plants
Family legume (Fabaceae) like Onobrychis viciifolia.
Flower meadows reach with legume. Elevations: 100-1100m.