Dipnomorpha

 Marbled lungfish Protopterus aethiopicus, photographed by Steve.

Belongs within: Sarcopterygii.
Contains: Dipnoi.

The Dipnomorpha includes the lungfish and their fossil relatives, united by the presence of jointed radials in the pectoral fins. Members of this clade have a fossil record going back to the Early Devonian (Zhu & Yu 2002).

Synapomorphies (from Zhu & Yu 2002): Anterior margin of parietal slightly posterior to orbits; parietal-supraorbital contact absent; denticulated field of parasphenoid with spiracular groove; axis of pectoral fin skeletion with more than five axial elements; pectoral fin radials jointed, axial elements bearing symmetrical array of preaxial and postaxial radials; enamel lining present in pore canals.

<==Dipnomorpha
    |--+--Youngolepis [Youngolepididae, Youngolepiformes]ZY02
    |  |    `--Y. praecursor Zhang & Yu 1981S93
    |  `--DipnoiformesS93
    |       |--DipnoiTC71
    |       `--Diabolepis [Diabolepidida, Diabolepididae]ZY02
    |            `--D. speratus (Chang & Yu 1984)S93
    `--Porolepiformes [Holoptychiida, Porolepimorpha]ZY02
         |  i. s.: Powichthys thorsteinssoni Jessen 1975ZY02, S93
         |--Porolepis [Porolepididae]ZY13
         |    |--P. brevis Jarvik 1937S93
         |    |--P. elongata Jarvik 1937S93
         |    |--P. posnaniensis (Kade 1858)S93
         |    |--P. siegenensis Gross 1936S93
         |    `--P. spitsbergensis Jarvik 1937S93
         `--HoloptychiidaeS93
              |--Holoptychius hibbertiT64
              `--GlyptolepisS93
                   |--G. benedeniC02
                   |--G. groenlandicaGX17
                   `--G. leptopterus Agassiz 1844S93

*Type species of generic name indicated

References

[C02] Clement, G. 2002. Large Tristichopteridae (Sarcopterygii, Tetrapodomorpha) from the late Famennian Evieux Formation of Belgium. Palaeontology 45: 577–593.

[GX17] Giles, S., G.-H. Xu, T. J. Near & M. Friedman. 2017. Early members of ‘living fossil’ lineage imply later origin of modern ray-finned fishes. Nature 549: 265–268.

[S93] Schultze, H.-P. 1993. Osteichthyes: Sarcopterygii. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 657–663. Chapman & Hall: London.

[T64] Tate, G. 1864. Description of a sea-star, Cribellites carbonarius, from the Mountain Limestone formation of Northumberland, with a notice of its association with Carboniferous plants. Report of the British Association for the Advancement of Science 33 (Notices and Abstracts): 88–89.

[TC71] Thomson, K. S., & K. S. W. Campbell. 1971. The structure and relationships of the primitive Devonian lungfish—Dipnorhynchus sussmilchi (Etheridge). Yale University Peabody Museum of Natural History Bulletin 38: 1–109.

[ZY02] Zhu, M., & X. Yu. 2002. A primitive fish close to the common ancestor of tetrapods and lungfish. Nature 418: 767–770.

[ZY13] Zhu, M., X. Yu, P. E. Ahlberg, B. Choo, J. Lu, T. Qiao, Q. Qu, W. Zhao, L. Jia, H. Blom & Y. Zhu. 2013. A Sliurian placoderm with osteichthyan-like marginal jaw bones. Nature 502: 188–193.

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