Published online by Cambridge University Press: 10 July 2009
There has been considerable confusion in the determination of I. suspiciosus Wesmael. In fact, in Wesmael's series of this species in the Brussels Museum, the two species here differentiated were both represented. However, only one of these species agreed completely with his original description, and unfortunately this is not the species determined as suspiciosus by Thomson and by Roman. This latter form I regard as being a subspecies of I. septentrionalis Holmgren.