Diel activity and reproductive isolation in a diverse assemblage of Neotropical skippers (Lepidoptera: Hesperiidae)

A sample of over 400 co-occurring species of Neotropical Hesperiidae attracted to artificial lures was used to test for temporal structure among species and explore potential consequences of temporal partitioning within assemblages. Five years of intermittent transect samples at the same site revealed that diel activity was significantly partitioned among subfamilies, genera and species within this species assemblage. Calculations of reproductive isolation indicate that partitions in activity times are sufficient to provide significant prezygotic reproductive isolation among some congeneric species pairs. Temporal patterns in this assemblage are considered in light of field observations and temporal partitions are examined as a potential isolating barrier among insects. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society 2008, 94, 723–736.