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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