Dermestid beetles are scavengers that feed on dried animal tissue and plant material. A number of species spanning several dermestid genera are pestiferous and can cause product damage and economic burden. Of great concern is the Khapra Beetle, Trogoderma granarium, a notorious pest of stored grain. Trogoderma granarium is currently not established in the United States; however, interception of this species is increasingly frequent at U.S. borders. Rapid identification of the Khapra Beetle is difficult because of morphological similarity with native Trogoderma species and due to the fact that key diagnostic characters are often damaged during transport. This study had three main objectives: 1) obtain native Trogoderma and other dermestid specimens for DNA analyses, 2) develop a rapid and accurate molecular method of detection for T. granarium and 3) test the monophyly of the North American Trogoderma species and comment on related dermestid genera.To accomplish the first objective, a network of collaborators collected dermestid specimens by hand, sorted through flight intercept traps, and used a commercially available Trogoderma sex-pheromone lure (Trogodermal) to attract and capture the beetles or provided preserved specimens. Individuals representing 12 dermestid genera were collected. Less than 100 total dermestid individuals were collected without the use of the pheromone lure; however, over 3,000 dermestid specimens from the United States, Canada and Panama were collected using the pheromone lure. In total, nine Trogoderma species and four other dermestid genera were collected. This is the first documentation of intergeneric dermestid response to the chemical Trogodermal.To accomplish the second objective, DNA was extracted from representatives of each Trogoderma species and other dermestid genera from my collection of greater than 3,000 specimens. Ten of 14 native Trogoderma species were used in the development of the assays. Partial gene regions were sequenced and PCR- and RT-PCR primers were developed for the specific detection of T. granarium. These two PCR methods successfully diagnosed T. granarium compared to the ten native Trogoderma species.To accomplish the third objective, DNA was amplified and partial gene regions were sequenced for 193 taxa including 12 Trogoderma species, four subspecies and specimens representing 10 other dermestid genera. While the taxonomy of North American Trogoderma has been extensively studied and the natural history of the pestiferous species is well understood, the relationship among North American Trogoderma species has not been investigated in detail. In addition, the greater dermestid subfamily taxonomic designation is under continuous fluctuation. Using mitochondrial and nuclear genes we reconstructed a phylogeny of North American Trogoderma and related genera. Trogoderma was recovered monophyletic with the exclusion of T. fasciferum. The T. sternale subspecies were polyphyletic and the clade included four other Trogoderma species. Orphilus was well supported and was sister to the remaining dermestids. Novelsis and Attagenus were polyphyletic and the phylogenetic placement of Thylodrias remained unresolved.
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