Comparative Biologies of the Cryptic, Sympatric Species, Trupanea bisetosa and T. nigricornis (Diptera: Tephritidae) in Southern California

The biologies of the sympatric, cryptic species, Trupanea nigricornis (Coquillett), a flower head-infesting fruit fly attacking a wide range of hosts in 8 tribes, 33 genera, and at least 71 species of Asteraceae, and T. bisetosa (Coquillett), an oligophage attacking only 6 hosts in 4 genera of the tribe Heliantheae, are described and compared. A major biological distinction between these species was their ovipositional behavior, whereby females oviposited different numbers of eggs at different sites in different developmental stages of flower heads of their hosts. The larvae of these species showed minor differences in their feeding behaviors, and their puparia were formed and located similarly in host flower heads. Development from egg to adult under field conditions lasted up to 35 d for each species. These species showed subtle differences in their courtship and mating behaviors, and substantial differences in the daily timing of courtship.