Date of Graduation
5-2026
Document Type
Thesis
Degree Name
Bachelor of Science in Biology
Degree Level
Undergraduate
Department
Fulbright College of Arts and Sciences Dean's Office
Advisor/Mentor
Don Shepard
Committee Member
Sarah DuRant
Second Committee Member
Daniel Lessner
Third Committee Member
Jill Geisler Wheeler
Abstract
Plethodontid salamanders possess some of the most structurally variable mitochondrial genomes among vertebrates, yet complete mitogenomic data remain limited for many clades. In particular, the Plethodon glutinosus species group is underrepresented, with few complete mitochondrial genomes available despite its ecological and evolutionary importance. Here, we assembled and annotated complete mitochondrial genomes for six species spanning the major lineages within the P. glutinosus group using publicly available whole genome sequencing data. Mitogenome sizes ranged from 16,736 to 17,772 base pairs (bp) and contained 13 protein-coding genes, 2 rRNA genes, and a non-coding control region, with variation observed in tRNA gene number due to lineage-specific duplications. Notably, we identified a 1,002-bp duplication in the intergenic spacer region of Plethodon cheoah and a 578-bp duplication spanning the WANCY region in Plethodon cylindraceus, both representing early-stage duplication events consistent with the duplication–random loss model. Phylogenetic analyses based on protein-coding genes recovered well-supported relationships consistent with most prior studies. These results expand the number of complete mitogenomes available for the P. glutinosus group and provide additional examples of structural variation within plethodontid mitochondrial genomes. Continued sampling across species and populations will likely reveal even greater diversity, underscoring the value of this group for investigating the mechanisms underlying mitochondrial genome evolution.
Keywords
Plethodontidae; mtDNA; WANCY; Duplications
Citation
Jordan, L., & Shepard, D. (2026). Six New Mitochondrial Genomes for Slimy Salamanders (Plethodon glutinosus group) and their Phylogenetic Relationships. Biological Sciences Undergraduate Honors Theses Retrieved from https://scholarworks.uark.edu/biscuht/146
