Axonophora

 Specimens of Amplexograptus, probably A. perexcavatus, photographed by Mark Wilson.

Belongs within: Bireclinata.
Contains: Neograptina, Dicranograptidae, Climacograptidae, Lasiograptidae, Orthograptinae.

The Diplograptidae are a group of graptoloids known from the Lower Ordovician to the Lower Silurian. Members of this family have a biserial rhabdosome with a symmetrical proximal end (Fortey & Cooper 1986), with the second theca having a right-handed origin from the first theca. They include the distinctive Lower Ordovician genus Dicaulograptus, which possesses a minute rhabdosome with introverted apertures adjacent to long slender spines at the base of the pleural lists (Bulman 1970).

Axonophora (see below for synonymy)M14
    |--Exigraptus Mu in Mu et al. 1979MCM09, M14
    |    |--E. clavusSL04
    |    `--E. uniformisMCM09
    `--+--‘Undulograptus’ sinodentatusMCM09
       `--+--‘Undulograptus’ marathonensisMCM09
          `--+--NeograptinaM14
             `--+--DicranograptidaeMCM09
                |--+--ClimacograptidaeM14
                |  `--Archiclimacograptus Mitchell 1987M14
                |       |  i. s.: A. angulatusM14
                |       |--A. modicellus (Harris & Thomas 1935)M14, M10
                |       `--+--A. decoratusM14
                |          `--+--A. sebyensisM14
                |             `--+--A. meridionalisM14
                |                `--A. skagensisM14
                `--+--Eoglyptograptus Mitchell 1987M14, R93
                   |    |--E. bulmaniM14
                   |    `--E. gerhardiM14
                   `--+--Pseudoamplexograptus Mitchell 1987M14, R93
                      |    |--P. confertus (Nicholson 1868)R93
                      |    `--P. distichusM10
                      `--+--LasiograptidaeM14
                         `--OrthograptinaeM14
Axonophora incertae sedis:
  Apiograptus Cooper & McLaurin 1974M14
  Levisograptus Maletz 2011M14
    |--L. austrodentatus [=Undulograptus austrodentatus]M14
    |--L. dentatusM14
    |--L. dicellograptoidesM14
    |--L. marathonensisM14
    |--L. primusM14
    |--L. sinicus (Mu & Lee 1958)M14, M10 [=Undulograptus sinicusM14]
    `--L. sinograptusM14
  Urbanekograptus Mitchell 1987R93
  Fenhshiangograptus Hong 1957M14
  Oepikograptus Obut 1987M14
    `--O. bekkeriM14
  Prorectograptus Li 1994M14
  Pseudamplexograptus Mitchell 1987M14
    `--P. distichusM14

Axonophora [Diplograptacea, Diplograptidae, Diplograptina, Diplograptinae, Diplograptoidea, Eoglyptograptidae, Eoglyptograptinae, Orthograptidae, Virgellina]M14

*Type species of generic name indicated

References

[M10] Maletz, J. 2010. Xiphograptus and the evolution of virgella-bearing graptoloids. Palaeontology 53 (2): 415–439.

[M14] Maletz, J. 2014. The classification of the Pterobranchia (Cephalodiscida and Graptolithina). Bulletin of Geosciences 89 (3): 477–540.

[MCM09] Maletz, J., J. Carlucci & C. E. Mitchell. 2009. Graptoloid cladistics, taxonomy and phylogeny. Bulletin of Geosciences 84 (1): 7–19.

[R93] Rickards, R. B. 1993. Graptolithina. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 537–542. Chapman & Hall: London.

[SL04] Servais, T., J. Li, L. Stricanne, M. Vecoli & R. Wicander. 2004. Acritarchs. In: Webby, B. D., F. Paris, M. L. Droser & I. G. Percival (eds) The Great Ordovician Biodiversification Event pp. 348–360. Columbia University Press.

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