Amphigastropoda

Steinkern of Pelagiella, from Landing et al. (2002).

Belongs within: Helcionelliformes.
Contains: Bellerophontidae.

The name 'Amphigastropoda' has been used for an assemblage of planispiral or cap-shaped, mostly Palaeozoic molluscs. Primarily centered around the Bellerophontoidea, other groups that have been included in the Amphigastropoda by various authors include the Pelagielliformes, Cyrtolitidae and Tryblidiidae. The grouping was originally proposed on the basis that these animals were gastropod-like but untorted; however, studies of muscle scars the genus Bellerophon itself indicate that it, at least, underwent torsion, and the Amphigastropoda in the broad sense is probably a polyphyletic assemblage (Peel 1972).

Amphigastropoda
    |--Cyrtolitida BR05
    |--Tryblidiidae T59 [Tryblidiida BR05]
    |    |--Helcionopsis Ulrich & Schofield 1897 T59
    |    |    `--*H. striata T59
    |    |--Pilina Koken 1925 T59
    |    |    `--*P. unguis [=Tryblidium unguis] T59
    |    |--Tryblidium Lindström 1880 T59
    |    |    |--*T. reticulatum T59
    |    |    `--T. nycteis (Billings 1862) [=Metoptoma nycteis] T59
    |    `--Vallatotheca Foerste 1914 T59
    |         |--*V. manitoulini T59
    |         `--V. elegantula (Chapman 1916) (see below for synonymy) T59
    |--Pelagielliformes [Orthostrophina, Pelagiellacea, Pelagiellida, Pelagielloidea] BR05
    |    |--Pelagiellidae BR05
    |    |    |--Costipelagiella Horny 1964 P02
    |    |    |--Tianzhushanospira Yu 1979 P02
    |    |    |--Proeccyliopterus Kobayashi 1939 [Proeccyliopteridae] BR05
    |    |    |--Protoscaevogyra Kobayashi 1939 [Protoscaevogyridae] BR05
    |    |    |--Tannuspira Missarzhevsky 1989 P02
    |    |    |    `--T. magnifica Missarzhevsky 1989 P02
    |    |    `--Pelagiella Matthew 1895 BR05
    |    |         |--P. adunca Missarzhevsky 1966 P02
    |    |         |--P. lorenzi Kobayashi 1939 P02
    |    |         `--P. madianensis Zhou & Xiao 1984 P02
    |    `--Aldanellidae BR05
    |         |--Paraaldanella Golubev 1976 P02
    |         |--Nomgoliella Missarzhevsky 1981 P02
    |         |    |--N. australiensis P02
    |         |    |--N. rotunda P02
    |         |    `--N. sinistrovolubilis Missarzhevsky 1981 P02
    |         `--Aldanella Vostokova 1962 BR05
    |              |--A. crassa Missarzhevsky 1969 P02
    |              `--+--A. utchurica Missarzhevsky 1969 P02
    |                 `--+--A. rozanovi Missarzhevsky 1966 P02
    |                    `--A. operosa Missarzhevsky 1966 P02
    `--Bellerophontoidea [Bellerophontacea, Bellerophontida, Bellerophontina] BR05
         |--Bellerophontidae BR05
         |--Bucanella Meek 1871 [=Bucaniella Fischer 1885; Bucanellinae, Bucaniellinae] BR05
         |--Tremanotus Hall 1867 [=Trematonotus Fischer 1885; Tremanotidae, Tremanotinae, Trematonotidae] BR05
         |--Tropidodiscus Meek & Worthen 1866 [Tropidodiscidae, Tropidodiscinae] BR05
         |--Pterothecidae BR05
         |    |--Pterotheca Salter 1852 [Pterothecinae] BR05
         |    |--Carinaropsis Hall 1847 [Carinaropsidae, Carinaropsinae] BR05
         |    `--Pedasiola Spriesterbach 1919 [Pedasiolinae] BR05
         |--Sinuitidae [Sinuitoidea] BR05
         |    |--Aiptospira Wang 1980 [Aiptospirinae] BR05
         |    |--Hispanosinuites Frýda & Gutierrez-Marco 1996 [Hispanosinuitinae] BR05
         |    `--Sinuitinae BR05
         |         |--Sinuites Koken 1896 BR05
         |         `--Protowarthia Ulrich & Scofield 1897 [Protowarthiidae] BR05
         |--Euphemitidae BR05
         |    |--Paleuphemites Horný 1962 [Paleuphemitinae] BR05
         |    `--Euphemitinae BR05
         |         |--Euphemites Warthin 1930 BR05
         |         `--Warthia Waagen 1880 W63
         |              |--*W. brevisinuata Waagen 1880 W63
         |              |--W. americana Girty 1909 W63
         |              |--W. micromphala (Morris 1845) (see below for synonymy) W63
         |              |--W. perspecta Fletcher 1958 W63
         |              `--W. stricta (Dana 1847) (see below for synonymy) W63
         `--Bucaniidae BR05
              |--Salpingostoma Roemer 1876 (see below for synonymy) BR05
              |--Undulabucania Wahlman 1992 [Undulabucaniinae] BR05
              |--Plectonotinae BR05
              |    |--Plectonotus Clarke 1899 [Plectonotini] BR05
              |    `--Boucotonotus Frýda & Manda 1997 [Boucotonotini] BR05
              `--Bucaniinae [Bucaniides] BR05
                   |--Grandostoma Horný 1962 [Grandostomatidae, Grandostomatinae] BR05
                   `--Bucania Hall 1847 BR05
                        |--B. angustafasciata Waagen 1880 W63
                        `--B. kattaensis Waagen 1880 [incl. B. k. var. carinata Wanner 1942] W63

Salpingostoma Roemer 1876 [Salpingostomatidae, Salpingostomatides, Salpingostomatinae, Salpingostominae] BR05

Vallatotheca elegantula (Chapman 1916) [=Helcionopsis elegantulum; incl. Tryblidium (Metoptoma) nycteis Cresswell 1893 non Metoptoma nycteis Billings 1862, Capulus nycteis, Helcionopsis nycteis] T59

Warthia micromphala (Morris 1845) [=Bellerophon micromphalus, B. (Warthia) micromphala, Goniatites (Agathiceras) micromphalus, G. (Prolecanites) micromphalus; incl. B. undulatus Dana 1847] W63

Warthia stricta (Dana 1847) [=Bellerophon strictus, Goniatites strictus; incl. B. contractus Sowerby in Jukes 1847 (n. n.)] W63

*Type species of generic name indicated

REFERENCES

[BR05] Bouchet, P., J.-P. Rocroi, J. Frýda, B. Hausdorf, W. Ponder, Á. Valdés & A. Warén. 2005. Classification and nomenclator of gastropod families. Malacologia 47 (1-2): 1-397.

Landing, E., G. Geyer & K. E. Bartowski. 2002. Latest Early Cambrian small shelly fossils, trilobites, and Hatch Hill dysaerobic interval on the Québec continental slope. Journal of Paleontology 76 (2): 287-305.

[P02] Parkhaev, P. Yu. 2002. Phylogenesis and the system of the Cambrian univalved mollusks. Paleontologicheskii Zhurnal 2002 (1): 27-39 (transl. Paleontological Journal 36 (1): 25-36).

Peel, J. S. 1972. Observations on some Lower Palaeozoic tremanotiform Bellerophontacea (Gastropoda) from North America. Palaeontology 15 (3): 412-422.

[T59] Talent, J. A. 1958-1959. Vallatotheca (Monoplacophora) in the Lower Devonian of Victoria. Mining and Geological Journal 6 (3): 3-4.

[W63] Waterhouse, J. B. 1963. Permian gastropods of New Zealand. Part 1 – Bellerophontacea and Euomphalacea. New Zealand Journal of Geology and Geophysics 6 (1): 88-112.