Goniatites

Specimens of Goniatites multiliratus, with the sutures visible on the smallest specimen. Image from here.

Belongs within: Ammonoidea.

Goniatites was a mid-Visean (Early Carboniferous) genus of ammonoid, the type of the Goniatitida. Like other goniatitids, Goniatites had an angular 'zig-zag' suture morphology. Members of this genus have been identified as index fossils in Europe and North America (Ross 1979).

Characters (from Korn et al. 2005): Moderately large, thickly discoidal to globular conch. Aperture and whorl expansion rate low to moderate (WER 1.45 to 2.00). Suture line with narrow, V-shaped or Y-shaped external lobe and moderately high median saddle. Ventrolateral saddle asymmetric, narrowly rounded or acute. Large, V-shaped adventive lobe. Ornament with strongly crenulated growth lines running in convex or biconvex course; some species with fine spiral ornament.

<==Goniatites de Haan 1825 [Goniatitidae] W77
    |--G. americanus R79
    |--G. baylorensis White 1891 P68
    |--G. choctawensis P68
    |    |--G. c. choctawensis P68
    |    |--G. c. barnettensis Miller & Youngquist 1948 P68
    |    `--G. c. cumminsi P68
    |--G. desideratus Walcott 1884 P68
    |--G. globulus P68
    |    |--G. g. globulus P68
    |    `--G. g. excelsus Meek 1876 P68
    |--G. granosus P68
    |--G. lutheri Clarke 1885 P68
    |--G. multiliratus Gordon 1962 P68
    |--G. mutabilis H84
    |--G. newsomi P68
    |--G. nodiger Clarke 1885 P68
    `--G. sphaericus P68

*Type species of generic name indicated

REFERENCES

[H84] Hyatt, A. 1883–1884. Genera of fossil cephalopods. Boston Soc. Nat. History, Proc. 22: 253–338.

Korn, D., C. Klug & R. H. Mapes. 2005. The Lazarus ammonoid family Goniatitidae, the tetrangularly coiled Entogonitidae, and Mississippian biogeography. Journal of Paleontology 79 (2): 356-365.

[P68] Purnell, L. R. 1968. Catalog of the type specimens of invertebrate fossils. Part I: Paleozoic Cephalopoda. United States National Museum Bulletin 262: 1–198.

[R79] Ross, C. A. 1979. Carboniferous. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A254–A290. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[W77] White, C. A. 1877. Report upon the invertebrate fossils collected in portions of Nevada, Utah, Colorado, New Mexico, and Arizona, by parties of the expeditions of 1871, 1872, 1873, and 1874. U.S. Geographical Surveys West of the One Hundredth Meridian 4 (1): 1–219, pls 1–21.