Mating banana stalk flies on the bark of a rotten moringa tree at Tehatta, India. The banana stalk flies (Neriidae) are slender and long-legged, are related to the Micropezidae, and found mainly in tropical regions. Neriids breed in rotting vegetation, such as decaying tree bark or rotting fruit. Males engage in spectacular battles for territory or access to females. The rivals elevate their bodies to an almost vertical posture and pound each other with the ventral surfaces of their heads, strike each other with their forelegs, or try to place each other in a headlock -Photograph: Soumyabrata Roy/NurPhoto /Rex/Shutterstock
I assume the headlock move is done after imbibing alcohol from rotten fruit, much like their human counterparts at pub closing time.
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