Monophyletic Hydrachnidiae, including Hydrovolzioidea, is strongly supported.
Terrestrial Parasitengonina do not form a monophyletic sister group to water mites.
Stygothrombidioidea is close to water mites but is not nested within this clade.
All superfamilies, except paraphyletic Hydryphantoidea, are strongly supported.
Protohydrachnidia, Euhydrachnidia, and Neohydrachnidia are strongly supported.