After Hou & Bergström, 1997, Whittington, Chang, Dean, Fortey, Jell, Laurie, Palmer, Repina, Rushton & Shergold, 1997 and Gon III, 2002
<==o †Eodiscina Kobayashi, 1939 [nom. correct. Moore, 1959 pro Eodiscidi Kobayashi, 1939a] `--o †Eodiscoidea Raymond, 1913 [nom. transl. Jell, 1975, ex Eodiscidae Raymond, 1913b] [Eodiscidea Richter, 1932; Dawsoniidea Kobayashi, 1943] |--o †Tsunyidiscus W. Chang, 1966 [taxonomic history] [Tsunyidiscidae S. Zhang, 1980] | |-- †T. niutitangensis (W. Zhang, 1964) [taxonomic history] | |-- †T. armatus (S. Zhang & Zhu in W. Zhang, Lu, et al., 1980) [taxonomic history] | |-- †T. liangshanensis (W. Zhang in W. Zhang, Lu, et al., 1980) [taxonomic history] | |-- †T. planilimbatus (S. Li, 1980) [taxonomic history] | |-- †T. orientalis (W. Zhang, 1953) [taxonomic history] | |-- †T. longquanensis (S. Zhang & Zhu in W. Zhang, Lu, et al., 1980) [taxonomic history] | `-- †T. chintingshanensis (Lu, 1942) [taxonomic history] |-- †Hebediscidae Kobayashi, 1944a [nom. transl. Jell in Whittington, et al., 1997, ex Hebediscinae Kobayashi, 1944a] [Delgadoiinae Kobayashi, 1943; Pagetiellinae S. Zhang in W. Zhang, Lu, et al., 1980; Dicerodiscinae S. Zhang in W. Zhang, Lu, et al., 1980] |-- †Calodiscidae Kobayashi, 1943 [nom. transl. Öpik, 1975a ex Calodiscinae Kobayashi, 1943] [Brevidiscinae Kobayashi, 1943; Neocobboldinae S. Zhang, in W. Zhang, Lu et al., 1980] |-- †Weymouthiidae Kobayashi, 1943 emend. Jell, 1975a [ladadiscinae Soloviev, 1964] |-- †Yukoniidae S. Zhang, 1980 [nom. transl. et emend. Jell, in Whittington et al., 1997 ex Yukoniinae S Zhang in W. Zhang, Lu et al., 1980] `-- †Eodiscidae Raymond, 1913 [Eodiscidae Raymond, 1913b emend. Jell, 1975a] [Dawsoniidae Resser, 1937; Pagetidae Kobayashi, 1935; Aulacodiscidae Hupé, 1954; Opsidiscidae Hupé, 1953b; Pagetiellinae S. Zhang in W. Zhang, Lu et al., 1980]
Eodiscina incertae sedis:
†Discagnostus Öpik, 1963 [possibly agnostid]
†D. spectator Öpik, 1963
Note:
Agnostida sensu lato [Agnostina & Eodiscina] have usually been classified as primitive trilobites. Hou & Bergström (1997) clearly state that, in their opinion, Agnostida sensu lato as traditionally defined and treated in the latest edition of “Treatise“ is actually a polyphyletic taxon, Eodiscina being a group of primitive trilobites and Agnostina an anomalous group of early Crustacean-like arthropods.
Reference(s):
- Gon III, S. M., 2002: Systematic listing of Trilobite families.
–iNet: http://www.aloha.net/~smgon/trisystem.htm - Hou & Bergström, 1997: Arthropods of the Lower Cambrian Chengjiang fauna, southwest China.
–Fossils & Strata, Number 45, 22nd December 1997, pp. 1-116 - Whittington, H. B., Chang, W. T., Dean, W. T., Fortey, R. A., Jell, P. A., Laurie, J. R., Palmer, A. R., Repina, L. N., Rushton, A. W. A. & Shergold, J. H., 1997: Systematic Description of the class Trilobita. 331-481.
in Kaesler, R. L., (eds.) 1997: Treatise on Invertebrate Paleontology, Part O, Arthropoda 1, Trilobita, Revisited, vol 1: Indroduction, Order Agnostida; Order Redlichiida.
–The Geological Society of America, Inc. and The University of Kansas, Boulder, Colorado & Lawrence, Kansas, 1997, xxiv-530