Lytoceratida

Crioceratites duvalii, copyright Hectonichus.

Belongs within: Ammonoidea.

The Lytoceratida are a lineage of ammonites known from the Jurassic and Cretaceous.

Characters (from Enseger & Keupp 2002): Conch thin-walled, usually weakly sculptured. Suture line with primary sutural formula ELU2U1I; suture elements microphyll (strongly slit). Siphuncle usually reaching marginal position after one whorl; septal necks becoming prochoanitic at very early ontogenetic stage.

<==Lytoceratida [Lytoceratina]
    |--Lytoceras CDH04 [Lytoceratidae EK02]
    |    |--L. argonautarum Anderson 1902 [=L. (Argonauticeras) argonautarum] MR77
    |    |--L. cornucopiae (Young & Bird 1822) EK02
    |    |--L. jurensis CDH04
    |    `--‘Ammonites’ lineatus [incl. A. lineatus var. opalina] CDH04
    |--Tetragonitoidea [Tetragonitaceae] EK02
    |    |--Tetragonitidae EK02
    |    |    |--Protetragonites Hyatt 1900 EK02
    |    |    `--Tetragonites Kossmat 1895 EK02
    |    |         `--T. popetensis TLY03
    |    `--Gaudryceratidae [Gaudryceratinae] EK02
    |         |--Zelandites Marshall 1926 EK02
    |         |--Anagaudryceras TLY03
    |         |    |--A. buddha RC02
    |         |    |--A. gainesi K79
    |         |    `--A. sacya (Forbes 1846) KK08
    |         `--Gaudryceras Grossouvre 1894 EK02
    |              |--G. denseplicatum TLY03
    |              |--G. jukesii K79
    |              |--G. tenuiliratum Yabe 1903 KK02
    |              `--G. varicostata M08
    `--Crioceratitidae [Crioceratitinae] EK02
         |--Aegocrioceras Spath 1924 EK02
         |    |--A. capricornu K79
         |    `--A. compressum Rawson 1975 EK02
         `--Crioceratites Levaille 1837 (Crioceratites) EK02
              |  i. s.: C. lardii K79
              |         C. latum K79
              |--C. (C.) duvalii W69
              `--+--C. (C.) nolani (Kilian 1910) W69, EK02
                 |--+--C. (C.) emericii W69
                 |  `--C. (Sornayites) paronai W69
                 `--+--C. (C.) majoricensis W69
                    `--C. (Pseudothurmannia) W69
                         |--+--C. (P.) balearis W69
                         |  `--C. (P.) ibizensis W69
                         `--+--C. (P.) angulicostatus W69 [=Pseudothurmannia angulicostata K79]
                            `--Hemihoplites W69
                                 |--H. astarte W69
                                 `--H. feraudianus W69

*Type species of generic name indicated

REFERENCES

[CDH04] Callomon, J. H., D. T. Donovan & M. K. Howarth. 2004. F. A. Quenstedt’s trinomial nomenclature of Jurassic ammonites. Palaeontology 47 (4): 1063–1073.

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

[K79] Kauffman, E. G. 1979. Cretaceous. In: Robison, R. A., & C. Teichert (eds) Treatise on Invertebrate Paleontology pt A. Introduction. Fossilisation (Taphonomy), Biogeography and Biostratigraphy pp. A418–A487. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas).

[KK08] Kennedy, W. J., & H. C. Klinger. 2008. Cretaceous faunas from Zululand and Natal, South Africa. The ammonite subfamily Lyelliceratinae Spath, 1921. African Natural History 4: 57–111.

[KK02] Klug, C., & D. Korn. 2002. Occluded umbilicus in the Pinacitinae (Devonian) and its palaeoecological implications. Palaeontology 45 (5): 917–931.

[M08] McMillan, I. K. 2008. Reappraisal of foraminiferal assemblages of the Santonia-Campanian Mzamba Formation type section, and their correlation with the stratigraphic succession of the KwaZulu Basin. African Natural History 4: 25–34.

[MR77] Murphy, M. A., & P. U. Rodda. 1977. The type specimens of Ammonites hoffmanni Gabb and Melchiorites indigenes Anderson (Cretaceous: Ammonoidea). Veliger 20 (2): 78–81.

[RC02] Riding, J. B., & J. A. Crame. 2002. Aptian to Coniacian (Early–Late Cretaceous) palynostratigraphy of the Gustav Group, James Ross Basin, Antarctica. Cretaceous Research 23: 739–760.

[TLY03] Tanabe, K., N. H. Landman & Y. Yoshioka. 2003. Intra- and interspecific variation in the early internal shell features of some Cretaceous ammonoids. Journal of Paleontology 77 (5): 876–887.

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