Leptopsylla is a genus of fleas belonging to the family Leptopsyllidae. The species Leptopsylla segnis was named by Carl Johan Schönherr in 1811.
Leptopsylla segnis, commonly known as the European mouse flea, is a widely distributed flea with the common host being the house mouse (Mus musculus). Severe infestations can cause anaemia. Adults have a both a genal and pronotal ctenidium.