Date of Award


Degree Name

Master of Science



First Advisor

Anderson, Frank


Anguispira is a group of common land snails found primarily in eastern North America. There are currently thirteen species recognized within Anguispira. A considerable amount of morphological variation is seen within and among these species, which has lead to much taxonomic confusion within the group. Additionally, because Anguispira species descriptions are based almost exclusively on shell shape and color characteristics, identifying specimens to species is often problematic. In an attempt to delimit species and clarify relationships within Anguispira, regions of the mitochondrial cytochrome oxidase subunit I (cox1), 16S ribosomal RNA (rrnL), and cytochrome b (cob) genes were sequenced from ninety-three individuals representing eleven putative Anguispira species. Variation in shell morphology was also investigated using multivariate analyses of variance. Molecular analyses revealed two currently recognized species (A. alternata and A. cumberlandiana) to be polyphyletic. Evidence also suggested that A. columba, previously synonymized with A. mordax, should be recognized as A. columba and no longer remain synonymized. In addition, several individuals belonging to four strongly supported lineages (which are currently questionable/unidentified) could result in new species.




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