A new species of the genus Eurystylops (Strepsiptera: Stylopidae) rediscovered after more than 100 years from Rophites bees (Hymenoptera: Halictidae)

A new species of Strepsiptera of the genus Eurystylops Bohart, 1943 (Stylopidae) from the Western Palearctic Region is described based on the female cephalothorax. Eurystylops ogloblini sp. nov. represents the first species described from the host bee of the genus Rophites Spinola, 1808. We have found Rophites clypealis Schwammberger, 1976, R. hartmanni Friese, 1902 and R. quinquespinosus Spinola, 1808 to be hosts of this species. We summarize all known data on the distribution of the genus Eurystylops in the Western Palearctic Region which suggest a recent decline of these rare parasites. We consider their rarity to be a direct consequence of the threat to their hosts, which are oligolectic bees. We also provide the first evidence of the existence of males in the genus Eurystylops based on an empty male puparium, which was noticed more than 100 years ago in R. quinquespinosus. A detailed redescription of the female cephalothorax of Eurystylops oenipontana Hofeneder, 1949 is provided. Eurystylops oenipontana is recorded from the Czech Republic for the first time.