the root (no rank)
Eukaryota (domain)
Metazoa (kingdom)
Annelida (phylum)
Hirudinea (class)
Rhynchobdelliformes (order)
Glossiphoniidae (family)
[hide inferior taxa]
Haementeria (genus)
Helobdella (genus)
Placobdella ornata (species)
Theromyzon (genus)