Coilopoceras colleti, from Cretaceous Atlas of Ancient Life.

Belongs within: Acanthoceratoidea.

The Pseudotissotiinae are an Upper Cretaceous (Lower Turonian to Coniacian) assemblage of ammonites with tubercles tending to develop into keels (Wright et al. 1996).

Characters (from Wright et al. 1996): Moderately to very involute; whorl section compressed with flat sides to globose or triangular; venter varying from oxyconic to rounded-fastigiate; primitively with ventrolateral and siphonal rows of tubercles tending to become keels; siphonal keel may be lost or become dominant over ventrolateral keels or tubercles; umbilical tubercles normally present at some stage; ribs broad and sparse or absent. Suture variable, tending to simplify.

<==Pseudotissotiinae [Hemitissotiinae]WCH96
    |--Eotissotia Barber 1957WCH96
    |     `--*E. simplex Barber 1957WCH96
    |--Donenriquoceras Wiedmann 1960WCH96
    |    `--*D. forbesiceratiforme Wiedmann 1960WCH96
    |--Wrightoceras Reyment 1954 [incl. Herrickiceras Cobban & Hook 1980, Imlayiceras Leanza 1967]WCH96
    |    |--*W. wallsi (Reyment 1954) [=Bauchioceras (*Wrightoceras) wallsi]WCH96
    |    |--‘Placenticeras’ costatum Herrick & Johnson 1900 [=*Herrickiceras costatum]WCH96
    |    `--*Imlayiceras’ washbournei Leanza 1967WCH96
    |--Hemitissotia Peron 1897 (see below for synonymy)WCH96
    |    |--*H. cazini Peron 1897WCH96
    |    |--H. galeppei (Pervinquière 1907) [=*Allotissotia galeppei]WCH96
    |    `--H. michaleti (Peron 1897) [=*Plesiotissotia michaleti]WCH96
    |--Choffaticeras Hyatt 1903WCH96
    |    |--*C. (Choffaticeras) meslei (Peron 1897) [=Pseudotissotia meslei]WCH96
    |    `--C. (Leoniceras Douvillé 1911)WCH96
    |         |--C. (*L.) luciae (Pervinquière 1907) [=Pseudotissotia (Choffaticeras) luciae]WCH96
    |         `--‘Leoniceras’ discoidaleHK81
    |--Thomasites Pervinquière 1907 (see below for synonymy)WCH96
    |    |--*T. rollandi (Peron 1889) [=Pachydiscus rollandi]WCH96
    |    |--T. gongilense (Woods 1911) [=Vascoceras gongilense, *Gombeoceras gongilense]WCH96
    |    |    |--T. g. gongilenseHK81
    |    |    `--T. g. lautum [=Gombeoceras gongilense lautum]HK81
    |    `--‘Pseudotissotia’ koulabica Kler 1908 [=*Ferganites koulabicus, *Koulabiceras koulabicum]WCH96
    `--+--Pseudotissotia Peron 1897 (see below for synonymy)WCH96
       |    |--*P. galliennei (Orbigny 1850) [=Ammonites galliennei]WCH96
       |    |--P. nigeriensis (Woods 1911) [=Hoplitoides nigeriensis, *Bauchioceras nigeriense]WCH96
       |    |--*Discovascoceras’ tesselitense Collignon 1957WCH96
       |    `--*Furoniceras’ trumpyi Collignon 1957WCH96
       `--Coilopoceratidae [Hoplitoidinae]WCH96
            |--Erichsenites Magalhães 1953WCH96
            |    `--*E. mirabilis (Pervinquière 1907) [=Hoplitoides mirabilis]WCH96
            |--Hoplitoides Koenen 1898WCH96
            |    |--H. ingens (Koenen 1897) [=Neoptychites ingens; incl. *H. latesellatus Koenen 1898]WCH96
            |    `--H. gibbosulusWCH96
            |         |--H. g. gibbosulusWCH96
            |         `--H. g. bipartitusWCH96
            `--Coilopoceras Hyatt 1903 (see below for synonymy)WCH96
                 |--*C. colleti Hyatt 1903WCH96
                 |--C. glebosum (Reyment 1954) [=*Glebosoceras glebosum]WCH96
                 |--*Vredenburgia’ khadluensis Chiplonkar & Ghare 1976WCH96
                 |--C. laraenseP93
                 |--*Namadoceras’ scindiae Vredenburg 1907WCH96
                 |--C. springeriP93
                 `--C. stephaniP93

Coilopoceras Hyatt 1903 [incl. Glebosoceras Reyment 1954, Namadoceras Vredenburg 1907, Vredenburgia Chiplonkar & Ghare 1976]WCH96

Hemitissotia Peron 1897 [incl. Allotissotia Parnes 1964, Heterammonites Coquand 1880 (n. d.), Plesiotissotia Peron 1897]WCH96

Pseudotissotia Peron 1897 [incl. Bauchioceras Reyment 1954, Discovascoceras Collignon 1957, Furoniceras Collignon 1957]WCH96

Thomasites Pervinquière 1907 [incl. Ferganites Stankievich & Pojarkova 1969 non Miklukho-Maklay 1959, Gombeoceras Reyment 1954, Koulabiceras Atabekian 1966]WCH96

*Type species of generic name indicated


[HK81] Hancock, J. M., & W. J. Kennedy. 1981. Upper Cretaceous ammonite stratigraphy: some current problems. 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. 531–553. Academic Press.

[P93] Page, K. N. 1993. Mollusca: Cephalopoda (Ammonoidea: Phylloceratina, Lytoceratina, Ammonitina and Ancyloceratina). In: Benton, M. J. (ed.) The Fossil Record 2 pp. 213–227. Chapman & Hall: London.

[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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