Bibio marci or the St Marks Fly, it gets this name because the adults emerge about the 25th April or St Marks Day. This species shows strong sexual di

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Bibio marci or the St Marks Fly, it gets this name because the adults emerge about the 25th April or St Marks Day. This species shows strong sexual dimorphism, meaning that males and females look very different. This macro photograph shows a male, identified by the large eyes which help them to spot and capture females in the mating swarm, also to see and chase off rival males.

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Size: 5175px × 3377px
Photo credit: © SINCLAIR STAMMERS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: bibio, dimorphism, diptera, fly, march, marco, marks, sexual, spring, st