The Clitellata are a class of annelid worms, characterized by having a clitellum – the 'collar' that forms a reproductive cocoon during part of their life...

Haplotaxida might eventually be up-ranked to subclass status within the Clitellata or an expanded Oligochaeta, with the present suborders advancing to order...

"Molecular evidence for the non-monophyletic status of Naidinae (Annelida, Clitellata, Tubificidae)". Molecular Phylogenetics and Evolution. 40 (2): 570–584...

is a name often given to a variety of large invertebrates in the class Clitellata, many being from the family Megascolecidae. It may refer to: Giant Gippsland...

monophyletic group uniting several polychaetes and the monophyletic class Clitellata. It is the sister group of Errantia. The phylogeny of polychaetes is slowly...

Pietro (2000). "Evolution and biogeography of megadriles (Annelida, Clitellata)". Italian Journal of Zoology. 67–2 (2): 179–201. doi:10.1080/11250000009356313...

Palaeacanthocephala (ancient thornheads) Polyacanthocephala Acoela Nemertodermatida Clitellata (earthworms) Polychaeta (bristle worms) Sipuncula (peanut worms) Arachnida...

different from that of other annelids, including other members of the Clitellata. In leeches there are no septa, the connective tissue layer of the body...

"Taxonomic Considerations and Distribution of the Branchiobdellida (Annelida: Clitellata) on the North American Continent". Northeastern Naturalist. 9 (4): 451–468...

al. "DNA‐based phylogeny of the marine genus Heterodrilus (Annelida, Clitellata, Naididae)." Journal of Zoological Systematics and Evolutionary Research...