First records of Brephidium exilis (Boisduval) (Lepidoptera: Lycaenidae) from south-western part of the Arabian Peninsula suggests possible further dispersal into North Africa

During surveys in February and September 2022 focused on the butterfly fauna of the mountainous southwestern part of the Kingdom of Saudi Arabia, we unexpectedly discovered the alien species Western Pygmy Blue (Brephidium exilis) at two locations. These are the first records of this species in the southwestern part of the Arabian Peninsula, where its main range was previously restricted to the Arabian Gulf region. Adults were observed at atypical elevations and in forested areas. These findings indicate greater ecological plasticity of the species and possibly suggest its further dispersal into North Africa and the Mediterranean region. While long distance dispersal from Arabian gulf region seems the most reasonable origin, human introduction via transfer of host plants could not be excluded.