Heteroceras tardieui, from Wright et al. (1996).

Belongs within: Ancyloceratidae.

The Heteroceratidae are a Lower Cretaceous (Lower Barremian to Lower Aptian) lineage of heteromorph ammonites with an initial helix opening to a long shaft and large terminal hook (Wright et al. 1996).

<==Heteroceratidae [Colchiditinae, Heteroceratinae]WCH96
    |--Uhligia Koenen 1904WCH96
    |    `--*U. minuta (Neumayr & Uhlig 1881) [=Crioceras minutum]WCH96
    |--Hemibaculites Hyatt 1900WCH96
    |    `--*H. obliquatus (Orbigny 1842) [=Toxoceras obliquatum]WCH96
    |--Martelites Conte 1989WCH96
    |    |--*M. marteli Conte 1989WCH96
    |    `--M. sarasiniWCH96
    |--Kutatissites Kakabadze 1970 [incl. Simionescites Avram 1976]WCH96
    |    |--*K. bifurcatus Kakabadze 1970WCH96
    |    `--K. princeps (Avram 1976) [=*Simionescites princeps]WCH96
    |--Colchidites Djanélidzé 1926 [incl. Santandericeras Royo y Gomez 1945]WCH96
    |    |--*C. colchicus Djanélidzé 1926WCH96
    |    |--*Santandericeras’ apolinari Royo y Gomez 1945WCH96
    |    `--C. shaoriensisW69
    |--Imerites Rouchadzé 1933 (see below for synonymy)WCH96
    |    |--I. cristatus (Orbigny 1842) (see below for synonymy)WCH96
    |    |--I. densecostatus Renngarten 1926 [=*Paraimerites densecostatus]WCH96
    |    |--I. dichotomus (Eristavi 1955) [=Colchidites (Imerites) dichotomus, *Eristavia dichotoma]WCH96
    |    `--I. favreiWCH96
    `--Heteroceras Orbigny 1849 [incl. Lindigia Karsten 1858]WCH96
         |  i. s.: H. astierianum Orbigny 1851WCH96
         |         *Lindigia’ helicoceroides Karsten 1858WCH96
         |--H. (Heteroceras)WCH96
         |    |--*H. (H.) emericianum (Orbigny 1842) [=Turrilites emericianus]WCH96
         |    `--H. (H.) tardieuiWCH96
         `--H. (Argvethites Rouchadzé 1933)WCH96
              `--H. (*A.) lashense Rouchadzé 1933WCH96

Imerites Rouchadzé 1933 [=Escragnolleites Sarkar 1954; incl. Atopoceras Jaubert in Kilian 1889 (n. n.), Eristavia Kakabadze 1971, Paraimerites Kakabadze 1967]WCH96

Imerites cristatus (Orbigny 1842) [=Crioceras cristatum; incl. Heteroceras giraudi Kilian 1889, *Escragnolleites giraudi, *Imerites giraudi]WCH96

*Type species of generic name indicated


[W69] Wiedmann, J. 1969. The heteromorphs and ammonoid extinction. Biological Reviews 44: 563–602.

[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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