@article {KNZ001273,
	title = {Highly polymorphic microsatellites in the North American snakeweed grasshopper, Hesperotettix viridis},
	journal = {Journal of Orthoptera Research},
	volume = {18},
	year = {2009},
	pages = {19 -21},
	abstract = {<p>Microsatellite markers are preferred for fine-scale population genetic studies requiring high resolution. The grasshopper Hesperotettix viridis (Thomas) is an oligophagous species that feeds on composites and often exhibits locally restricted diets. Divergence in host plant use in some localities is seen where co-occurring subpopulations select alternate plant species, as expected with the evolution of host shifts and associated lineage divergence. To characterize the host-associated divergence patterns among populations of H. viridis, we developed markers from two microsatellite-enriched genomic libraries. Here we report the characterization and optimization of seven polymorphic di- and tri-nucleotide microsatellite loci for this species. One hundred and six individuals from 5 populations were tested for polymorphism. The number of alleles varied from 4 to 38 in all the populations. Ho ranged from 0.339 to 0.790. Homozygote excess was observed across loci, perhaps due to inbreeding. This is the first report of microsatellite markers for the subfamily Melanoplinae.</p>},
	keywords = {LTER-KNZ, Hesperotettix viridis, host-associated divergence, local adaptation, microsatellite markers, snakeweed grasshopper},
	doi = {10.1665/034.018.0111},
	url = {https://bioone.org/journals/Journal-of-Orthoptera-Research/volume-18/issue-1/034.018.0111/Highly-Polymorphic-Microsatellites-in-the-North-American-Snakeweed-Grasshopper-iHesperotettix/10.1665/034.018.0111.full},
	author = {Grace, T. and Anthony Joern and Brown, S.J. and Apple, J.L. and Wisely, S.M.}
}
@phdthesis {KNZ001283,
	title = {Host associated genetic divergence and sexual isolation in the grasshopper Hesperotettix viridis (Orthoptera: Acrididae)},
	volume = {PhD Dissertation},
	year = {2009},
	pages = {1 -127},
	school = {Kansas State University},
	type = {Ph.D. Thesis},
	address = {Manhattan, KS},
	abstract = {<p>Understanding evolutionary processes that structure genetic variation associated with lineage diversification and speciation is a central problem. Shifts in host plant use by insect herbivores and subsequent divergence in mating signals can lead to sexual isolation, especially when selection for specialization on different hosts restricts gene flow among populations. The grasshopper Hesperotettix viridis (Thomas) is an oligophagous grasshopper feeding on plants primarily in the host plant genera Gutierrezia and Solidago in Kansas. I used mitochondrial and microsatellite genetic markers to evaluate the diversification pattern and underlying evolutionary mechanisms of two putative host races of H. viridis. I also quantified host preferences, the degree of sexual isolation among putative host races and divergence in cuticular attributes to identify the nature and origins of initial barriers that isolated populations in the formative stages of divergence. mtDNA data revealed a star-shaped phylogeny, suggesting isolation in a single refugium ~110,000 years ago based on a molecular clock, followed by rapid population expansion. Microsatellite data reveal significant host-based genetic differentiation and structuring in H. viridis populations in Kansas, including a microsatellite locus under strong divergent selection. Neutral microsatellite loci did not reveal a differentiation pattern specific to host plant use. Significant host-based preferences by individuals that fed on two host plant groups were detected in host paired-feeding preference studies. No-choice mate selection experiments revealed preferences for individuals collected from the same host species independent of location with little mating observed between individuals from different host species. Significant differentiation in color and cuticular composition among different host plant races within the study area was also detected. Correlations between host choice, mate choice and phenotypic divergence were observed and this host associated divergence appears to have a genetic basis. Based on the results of this study, I conclude that divergent selection for host plant use underlies observed sexual isolation among populations in this species. Hesperotettix viridis populations in Kansas that fed on Solidago and Gutierrezia species represent two incipient host races, early stages of diversification that could lead to speciation in insect herbivores.</p>},
	keywords = {LTER-KNZ, Hesperotettix viridis, Host Associated Divergence, Microsatellites, Population genetics, sexual isolation, Speciation},
	url = {http://hdl.handle.net/2097/1541},
	author = {Grace, T.}
}
