Acanthobdellidea
Acanthobdellidea is an infraclass of primitive leeches; some authors place them in a separate subclass from the Hirudinea. However, the World [Register of Marine Species] places them within the Hirudinea, as a sister group to Euhirudinea, the true leeches.
Species in the group include Acanthobdella peledina, described by the German zoologist Adolph [Eduard Grube] in 1851, and A. livanowi, described in 1966.