Noteworthy Mammals from Sinaloa, Mexico

The report compiles mammal specimens collected in Sinaloa over multiple field seasons, documenting twenty noteworthy records that extend known ranges or clarify taxonomy. It provides locality data and measurements (external and cranial), mapped collection sites, and natural-history notes including habitat and trapping observations. Detailed comparisons focus on two small shrew taxa, evaluating external and skull metrics and pelage variation, and reassessing past taxonomic treatments to argue for distinguishing the forms. Tables and a figure support the morphological comparisons. The account emphasizes specimen-based evidence for distributional, zoogeographic, and taxonomic conclusions and notes food and trapping behaviors observed in the field.