Redescription and Molecular Characterization of Placobdella michiganensis (Sawyer, 1972) (Hirudinida: Glossiphoniidae)

Placodella michiganensis (Sawyer, 1972) was originally described from free-living individuals collected from Mill Creek, St. Joseph County, Michigan, USA. The acquisition of contemporary specimens from its type locality has facilitated redescription of P. michiganensis. Placobdella michiganensis does not have a confusing taxonomic history like many other members of the genus Placobdella as it has only been collected two other times since its description. Placodella michiganensis is distinguished from its congeners by its five rows of whitish single-tipped papillae, genital and pre-anal patches, five pre-anal papillae, and absence of a dark dorsal-medial line. Placobdella michiganensis is a morphologically distinct species with a 16.0% to 22.0% difference in cytochrome c oxidase subunit I sequence data among congeners.