The following classification is from Cavalier-Smith (1998), Dzik&Krumbiegel1989 and Hou and Bergström. The following incorporates the list from the Wikipedia page Xenusiid and includes a number of monotypal taxa. The Onychophora is here made a paraphyletic taxon to avoid innumerable unplaced taxa that don't firt in the crown group. In addition, Cambrian lobopodians were at least morphologically closer to recent onychophores as shown by the fact that they would frequently cluster in cladistic analyses (e.g. Ramsköld & Chen (1998) Liu et al 2011) which at least indicates a phenetic similarity. Even so, this risks making the Onychoiphora into a watsebasket taxon. In any case, since the precise evolutionary relationships of these animals is still so uncertain, it should not be taken too seriously MAK120424
Superphylum Ecdysozoa Aguinaldo et al. 1997 (cont.
Phylum Lobopodia Snodgrass, 1938 (= Protarthropoda Lankester, 1904 = Lobopoda Cavalier-Smith 1998 ; soft cuticle; unjointed limbs with terminal claws ; both muscles and hydraulic pressure involved in locomotion; evolutionary grade, Camb-Rec).
Class Xenusia Dzik & Krumbiegel, 1989 (Paleozoic Lobopodians, traditionally included under Onychophora - paraphyletic/ancestral panarthropod grade - Cambr - Sil)
Mureropodia (intermediate between priapozoa and lobopodia)
Order Protonychophora Hutchinson 1930 (ancestral to other lobopodians)
Walcott, 1911 (monotypal, includes only Genus Aysheaia
Order Xenusiida Dzik & Krumbiegel, 1989 (paraphyletic taxon for Cambrian lobopodians; includes the Orders Scleronychophora Hou & Bergström 1995, Paronychophora Hou & Bergstrom, 1995, and Archonychophora Hou & Bergstrom, 1995)
Family Cardiodictyidae Hou & Bergstrom, 1995 (monotypal taxon - should probably be synonymised with anther family)
Family Eoconchariidae Hou & Shu, 1987 (= Microdictyonidae) (monogeneric taxon)
Conway Morris, 1977
Hou & Bergstrom, 1995 (filter feeders, reduced limbs, sedentary?)
Family Onychodictyidae Hou & Bergstrom, 1995 (monogeneric taxon - - should probably be synonymised with anther family)
Family Paucipodiidae Hou et al., 2004 (monotypal taxon)
Dzik & Krumbiegel, 1989 (large early lobopodians)
Order Siberiida Dzik 2011 (large advanced forms with grasping appendages)
Hutchinson, 1930 (terrestrial onychophora, velvet worms, e.g. Peripatus, Cambrian? or Carb to Rec)
Doyère 1840 (water bears, e.g. Echiniscus. Microscopic.Camb-Rec).
Subphylum Protarthropoda Lankester, 1904 (used here as paraphyletic bridging taxon between lobopodians and arthropods, and could be eqially placed in either phylum)
Collins, 1996 (paraphyletic grade of swimming and gilled lobopodians, include Anomalocaridid superpredators Camb to Dev)
Order Radiodonta Collins 1996
von Siebold and Stannius 1848 (jointed exoskelton Camb-Rec).