Labeceras ammonoides, from Wright et al. (1996).

Belongs within: Stephanocerataceae.

The Labeceratidae are Cretaceous ammonites that are primarily known from the Southern Hemisphere (Wright et al. 1996).

Characters (from Wright et al. 1996): Early whorls with coiling open, shallowly helical or planispiral; later whorls in contact or not; shell ending in hook; whorl section slightly inflated to very compressed; fine, branching ribs passing over venter; sometimes with umbilical or ventrolateral tubercles or both. Suture with bifid saddles and trifid lobes.

<==Labeceratidae [Aleteceratidae, Labeceratinae, Myloceratidae]WCH96
    |--Hamitoides Spath 1925WCH96
    |    `--*H. studerianus (Pictet 1847) [=Hamites studerianus]WCH96
    `--Labeceras Spath 1925 (see below for synonymy)WCH96
         |--*L. bryani Whitehouse 1926WCH96
         |--*Abadieceras’ altissimum Collignon 1950WCH96
         |--L. ammonoides (Etheridge 1909) [=Crioceras ammonoides, *Myloceras ammonoides]WCH96
         |--*Calliscaphites’ andinus Leanza 1970WCH96
         |--‘Myloceras’ auritulumBRW98
         |--‘Crioceras’ axonoides Etheridge 1909 [=Aleteceras axonoides]F71
         |--*Flindersites’ baccatus Whitehouse 1926WCH96
         |--L. besaireiP93
         |--L. crassetuberculatumP93
         |--‘Myloceras’ davidiF71
         |--*Ellipsoceras’ expansum Collignon 1950WCH96
         |--L. laqueus (Etheridge 1892) [=Hamites laqueus]F71
         |--‘Crioceras’ nautiloides Etheridge 1909 [=Aleteceras nautiloides]F71
         |--‘Myloceras’ orbiculus Whitehouse 1926F71
         |--*Euhemihoplites’ paradoxus Collignon 1964WCH96
         |--L. plasticumWCH96
         |--‘Crioceras’ plectoides Etheridge 1909 [=*Aleteceras plectoides]WCH96
         |--L. serotinumWCH96
         |--*Paraleptoceras’ singulare Leanza 1970WCH96
         |--‘Aleteceras’ tardicostatum Whitehouse 1926F71
         `--L. trifidum Whitehouse 1926 [incl. Crioceras laqueus Etheridge 1909 non Hamites laqueus Etheridge 1892]F71

Labeceras Spath 1925 [incl. Abadieceras Collignon 1950, Aleteceras Whitehouse 1926, Calliscaphites Leanza 1970, Ellipsoceras Collignon 1950, Euhemihoplites Collignon 1964, Flindersites Whitehouse 1926, Myloceras Spath 1925, Paraleptoceras Leanza 1970]WCH96

*Type species of generic name indicated


[BRW98] Beesley, P. L., G. J. B. Ross & A. Wells (eds) 1998. Fauna of Australia vol. 5. Mollusca: The Southern Synthesis. Part A. Australian Biological Resources Study: Canberra.

[F71] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1–167.

[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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