Bionomics of Brachys tessellatus1 in Coastal Plain Scrub Oak Communities

Abstract

Brachys tessellatus (Fabr.) is a leaf miner of turkey oak, Quercus laevis Walter, in coastal plain sandhill communities of the southeastern United States. Adult beetles emerged in March coincidentally with bud break on host trees. Adult feeding in March and April preceded oviposition from April through June. Eggs were placed singly on the upper leaf surface against major veins and near leaf margins. Larval development through five instars occurred from May through September. Pupation and transformation occurred in leaf mines in the fall and winter. The sex ratio (female to male) was 1 to 0.24. A life table study showed only 13% of eggs hatched; the balance were lost to various physical, genetic, developmental, parasitic or predatory agencies. Only 15% of larvae and 43% of pupae completed development. Parasitoids and predators accounted for the majority of losses in these stages. Fourteen natural enemies, including two eulophid egg parasitoids, nine eulophid larval parasitoids, two chalcidid pupal parasitoids, and one clerid larval predator, were identified. Observations on adult behavior were related to temperature. Developmental patterns were found to minimize the impact of miner feeding on host leaves.