Comments on the Taxonomy and Geographic Distribution of North American Microtines

The authors reevaluate the taxonomy and geographic distribution of North American microtine rodents by reexamining museum specimens and resolving conflicting literature records. They compare skull and pelage measurements, tail and hind-foot lengths, and dental characters to reassign individuals to subspecies and to refine range boundaries. Diagnostic cranial features and age-related identification limits are documented, and previous identifications are corrected where specimen evidence warrants. Specimen-based maps and regional comparisons are used to illustrate morphological variation and clarify subspecific distributions.