<==o †Climatiiformes Berg, 1940
   |-- †Euthacanthus macnicolli Powrie, 1864 [E. macnicoli] L. Dev. Eu. [Euthacanthidae, Ethacanthidae (lapsus calami?)]
   |?-o Vesperaliidae Valiukevičius & Burrow, 2005
   |  |-- †Acanthacanthus ornatus Valiukevičius, 2003
   |  `-- †Vesperalia perplexa Valiukevičius, 2004 L.Sil. EEu.
   `--+--o Climatiida Berg, 1940
      |  |-- †Gyracanthidae Woodward, 1906
      |  `--o †Climatiidae Berg, 1940
      |     |--o †Brachyacanthus Egerton, 1860, L. Dev. Eu. 
      |     |  `-- †B. scutiger
      |     |--o †Cheiracanthoides Wells, 1944 [Helolepis] M. Dev. NA.
      |     |  |-- †C. comptus Wells, 1944
      |     |  |-- †C. proprius Valiukevicius, 1985
      |     |  |-- †C. rarus Valiukevicius, 1994
      |     |  |-- †C. borealis Valiukevicius, 1994
      |     |  |-- †C. estonicus Valiukevicius, 1998
      |     |  |-- †C. nativus Valiukevicius, 1998
      |     |  |-- †C. planus Valiukevicius, 1998
      |     |  |-- †C. wangi Burrow et al., 2000
      |     |  |-- †C. dolosus Burrow et al., 2000
      |     |  `-- †C. mosolovicus Valiukevicius, 2003
      |     |--o †Climatius Agassiz, 1845, U. Sil. L. Dev. Eu. NA. EEu.
      |     |  `-- †C. reticulatus Agassiz, 1845
      |     |-- †Eiffellepis werneri Vieth-Schreiner, 1983; M.Dev. Eu.
      |     |-- †Erriwacanthus Ørvik, 1967, U. Sil. Eu. L. Dev. EEu. 
      |     |--o †Latviacanthus L. Dev. EEu. 
      |     |  `-- †L. ventspilsensis
      |     |?-o †Nodacosta Gross, 1940; L.Dev. WNAm., L.-M.Dev. EEu.
      |     |  |-- †N. pauli Gross, 1940
      |     |  |?- ?†N. gemuendensis (Gross, 1933)
      |     |  `-- †N. denisoni Burrow, 2007
      |     |--o †Nostolepis Pander, 1856 sensu Valiukevičius & Burrow, 2005 [Dendracanthus; Diplacanthoides; Dontacanthus; Rhabdiodus] U. Sil. L. Dev. Eu. EEu. Gr. Spits.
      |     |  |-- †N. alta Märss, 1986
      |     |  |-- †N. amplifica Valiukevičius, 2003
      |     |  |-- †N. consueta Valiukevičius, 2003
      |     |  |-- †N. costata Goujet, 1976
      |     |  |-- †N. decora Valiukevičius, 2003
      |     |  |-- †N. gracilis Gross, 1971
      |     |  |-- †N. kernavensis Valiukevičius, 1985
      |     |  |-- †N. kozhymica Valiukevičius, 2003
      |     |  |-- †N. linleyensis C. G. Miller & Märss, 1999
      |     |  |-- †N. magnicostata Valiukevičius, 2003
      |     |  |-- †N. minima Valiukevičius, 1994
      |     |  |-- †N. musca Valiukevičius, 2003
      |     |  |-- †N. parathleta Valiukevičius, 2003
      |     |  |-- †N. striata Pander, 1856 [type]
      |     |  |-- †N. taimyrica Valiukevičius, 1994
      |     |  `-- †N. terraborea Valiukevičius, 2003
      |     |?-o †“Nostolepis” Pander, 1856
      |     |  |-- †“N.” alifera
      |     |  |-- †“N.” elegans
      |     |  |-- †“N.” robusta
      |     |  `--+-- †“N.” arctica Vieth, 1980
      |     |     `-- †“N.” fragilis Valiukevičius, 2003
      |     |?-o †Nostolepoides Burrow, 1997
      |     |  |-- †N. platymarginata Burrow, 1997
      |     |  `?- ?†N. mingyinensis Wang, 2003
      |     |--o †Parexus Agassiz, 1845, L. Dev. Eu.
      |     |  |-- †P. recurvus
      |     |  `-- †P. falcatus
      |     |--o †Pruemolepis M. Dev. Eu.
      |     |  `-- †P. wellsi
      |     |--o †Ptomacanthus Miles, 1973, L. Dev. Eu. EEu. 
      |     |  `-- †P. angelicus
      |     |-- †Sabrinacanthus L. Dev. Eu.
      |     |-- †Sevyacanthus elliotti Burrow, 2007; L.Dev. WNAm.
      |     |?-o †Tareyacanthus Valiukevičius, 1994
      |     |  |-- †T. magnificus Valiukevičius, 1994
      |     |  `-- †T. dissectus Valiukevičius, 1998
      |     |--o †Vernicomacanthus Miles, 1973, L. Dev. Eu.
      |     |  |-- †V. uncinatus
      |     |  `-- †V. waynensis
      |     |?- †Watsonacanthus Valiukevičius, 1979
      |     `-- †Wetteldorfia triangula Vieth-Schreiner, 1983; M.Dev. Eu. 
      `--o Diplacanthida Berg, 1940 [Diplacanthiformes Berg, 1940]
         |?- †Uraniacanthus spinosus
         |--o †Culmacanthidae
         |  `--o †Culmacanthus Long, 1983
         |     |-- †C. pambulensis Young, 1989b
         |     `-- †C. stewarti
         |--o †Tetanopsyridae
         |  `--o †Tetanopsyrus Gagnier et al., 1999; L. Dev. NNA.
         |     |-- †T. lindoei Gagnier et al., 1999
         |     `-- †T. breviacanthis Hanke, Davis & Wilson, 2001
         `--o †Diplacanthidae Woodward, 1891
            |--o †Diplacanthus Agassiz, 1844 [Rhadinacanthus] M. Dev. Eu. EEu. U. Dev. NA.
            |  |-- †D. longispinus Agassiz, 1844
            |  |-- †D. crassissimus Duff, 1842
            |  |-- †D. tenuistriatus
            |  |-- †D. ellsi
            |  |-- †D. horridus Woodward, 1892
            |  |-- †D. striatus
            |  |-- †D. carinatus Gross, 1973
            |  |-- †D. kleesmentae Valiukevičius, 1986
            |  |-- †D. gravis Valiukevičius, 1988
            |  |-- †D. poltnigi Valiukevičius, 2003
            |  `-- †D. solidus Valiukevičius, 2003
            |--o †Gladiobranchus Bernacsek & Dineley, 1977; L. Dev. NNA.
            |  `-- †G. probaton
            |--o †Ptychodictyon Gross, 1973; L.Dev. WNAm., M.Dev. EEu. 
            |  |-- †P. rimosum Gross, 1973
            |  |-- †P. sulcatum Gross, 1973
            |  |-- †P. distinctum Valiukevičius, 1979
            |  |-- †P. ancestralis Valiukevičius, in Valiukevičius & Karatajute-Talimaa, 1986
            |  `-- †P. americanum Burrow, 2007
            `--o †Rhadinacanthus Traquair, 1888
               `-- †R. longispinatus

Reference(s):