Physodoceras sp., from here.

Belongs within: Perisphinctaceae.

The Aspidoceratinae are a group of ammonites known from the Middle and Upper Jurassic, members of which possess laevaptychi (aptychi that are smooth on the exterior surface except for some very weak pustules, and bearing concentric growth lines on the interior surface) (Enseger & Keupp 2002).

<==Aspidoceratinae EK02
    |--Euaspidoceras Spath 1931 EK02
    |--Orthaspidoceras Spath 1925 EK02
    |--Pseudhimalayites Spath 1925 EK02
    |--Schaireria Checa 1985 EK02
    |--Aspidoceras Zittel 1868 EK02
    |    `--A. acanthicum H79
    |--Physodoceras Hyatt 1900 EK02
    |    `--P. avellanum H79
    `--Sutneria Zittel 1884 EK02
         `--S. subeumela H79

*Type species of generic name indicated


[EK02] Engeser, T., & H. Keupp. 2002. Phylogeny of the aptychi-possessing Neoammonoidea (Aptychophora nov., Cephalopoda). Lethaia 35: 79–96.

[H79] Hölder, H. 1979. Jurassic. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A390–A417. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

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