Neocomites

Neocomites neocomiensis, from here.

Belongs within: Neocomitidae.

Neocomites is a genus of ammonites known from the Lower Valanginian to the Lower Hauterivian of the Lower Cretaceous (Wright et al. 1996).

Characters (from Wright et al. 1996): Rather involute, with flat sides; ribs flexuous, prorsiradiate, branching in small sheaves from slight umbilical tubercles and generally branching irregularly higher up the side or intercalated; all ribs ending in small, slightly oblique bullae on either side of smooth, flat venter; on later whorls ribs may cross venter more or less transversely. Sutures with large, subsymmetrical, trifid L with parallel sides.

<==Neocomites Uhlig 1905WCH96
    |  i. s.: N. pachydicranusWCH96
    |         N. wichmanniR81
    |--N. (Neocomites) [incl. Busnardoites Nikolov 1966, Varlheidites Rawson & Kemper 1978]WCH96
    |    |--*N. (N.) neocomiensis (Orbigny 1841) [=Ammonites neocomiensis]WCH96
    |    |--‘Ammonites’ desori Pictet & Campiche 1860 [=*Busnardoites desori]WCH96
    |    `--N. (N.) peregrinus (Rawson & Kemper 1978)MBF15 [=*Varlheidites peregrinusWCH96]
    |--N. (Eristavites Nikolov 1966)WCH96
    |    `--N. (*E.) platycostatus Sayn 1907WCH96
    |--N. (Sabbaiceras) beaumugnensis (Sayn 1907)MBF15
    `--N. (Teschenites Thieuloy 1971)WCH96
         |--N. (*T.) neocomiensiformis (Uhlig 1902) [=Ammonites neocomiensiformis]WCH96
         |--N. (T.) callidiscusR81
         `--N. (T.) campylotoxusR81

*Type species of generic name indicated

References

[MBF15] Mourgues, F. A., L. G. Bulot & C. Frau. 2015. The Valanginian Olcostephaninae Haug, 1910 (Ammonoidea) from the Andean Lower Cretaceous Chañarcillo Basin, northern Chile. Andean Geology 42 (2): 213–236.

[R81] Rawson, P. F. 1981. Early Cretaceous ammonite biostratigraphy and biogeography. In: House, M. R., & J. R. Senior (eds) The Ammonoidea: The evolution, classification, mode of life and geological usefulness of a major fossil group pp. 499–529. Academic Press.

[WCH96] Wright, C. W., J. H. Calloman & M. K. Howarth. 1996. Treatise on Invertebrate Paleontology pt L. Mollusca 4, revised vol. 4. Cretaceous Ammonoidea. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

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