Redescription ofPlacobdella parasitica(Say, 1824) Moore, 1901 (Hirudinida: Glossiphoniidae)

Abstract

Placobdella parasitica (Say, 1824) was originally described from lakes of the “North-western region.” Leeches collected during May and June, 2012, from Minnesota, USA, the type locality of Hirudo parasitica Say, 1824, were consistent with P. parasitica (Say, 1824) Moore, 1901 as described by Say (1824). The acquisition of these specimens from the type locality facilitated redescription of P. parasitica. A neotype is designated to stabilize the concept of P. parasitica. In contrast to the papillated members of the genus Placobdella, P. parasitica does not have a confusing and problematic taxonomic history. Placobdella parasitica is differentiated from its congeners by its smooth dorsal surface (or sensillae present), simple (medial unpigmented yellow line) to elaborate (medial and paramedial marbled patches) pigmentation, and ventrum with 8 to 12 stripes. Molecular comparison of CO-I sequence data from P. parasitica revealed differences of 14% from Placobdella multilineata, 14% from Placobdella papillifera, 15% to 17% from Placobdella rugosa, 15% from Placobdella ornata and 16% to 17% from Placobdella ali.