Identification and phylogenetic characterization of select species of Buprestidae
(Coleoptera) and Sesiidae (Lepidoptera) wood boring insect families occurring
across the southeastern United States
Wood boring insect pests are of major importance in the United States. Each
year, this unique guild of arthropods causes millions of dollars in aesthetic and yield
damage leading to lost revenue. Feeding by larvae slows plant growth, reduces plant
vigor, and restricts yields. Many affected plants are eventually killed. Two insect
families are the focus of this seminar (i.e. Buprestidae and Sesiidae) and both contain
putative species complexes, three of which were investigated molecularly.
Understanding species complexes of economic and aesthetic importance within these two
families becomes important when determining appropriate management options.
The Chrysobothris femorata complex is composed of twelve species, six of which
were recently described. Many of members of the femorata complex have overlapping
plan host ranges and are largely sympatric in the eastern United States. Molecular
analysis of nuclear and mitochondrial genes can be used to evaluate evolutionary
relationships and develop species-specific diagnostics. Phylogenetic analyses in our
studies confirm the close evolutionary relationship between species within the femorata
complex. Taxa within the complex are highly polyphyletic and data suggests
interbreeding between sympatric species may be occurring. Creation of specific
molecular diagnostic tools may not be possible for species that have not yet fully
separated.
The clearwing moth tribe Synanthedonini contains many species of economic and
aesthetic importance to managers of commercially grown ornamental trees and shrubs, as
well as fruit, nut and perennial plant producers. An analysis of the mitochondrial
cytochrome oxidase I gene was performed to test taxonomic hypotheses within the tribe
traditionally based on morphology and to delineate molecular differences between
species of two potential complexes within the tribe (i.e. Podosesia spp. and Synanthedon
scitula). The inferred phylogeny challenges traditional assumptions about
Synanthedonini tribe members and suggests need to reassign two genera (i.e. Podosesia
and Sannina) and one species (S. rileyana). The Podosesia complex, which consists of
two species and one subspecies, appears to be in a state of incipient speciation. In
addition, evidence from two activity peaks in the seasonal flight times of Synanthedon
scitula do not appear to represent separate species, confirming recent research
hypotheses, but may instead indicate slower larval development influence by host plant
material on which immature stages feed. Genetic sequences generated by this study can
be used to positively identify several species, regardless of life stage.