Stigmadiscus

Stigmadiscus
Temporal range: Botomian[1]
Scientific classification
Kingdom:
Animalia
Phylum:
Arthropoda
Class:
Trilobita
Order:
Agnostida
Suborder:
Eodiscina
Superfamily:
Eodiscoidea
Family:
Weymouthiidae
Genus:
Stigmadiscus Rasetti, 1966.

Stigmadiscus Rasetti, 1966,[2] is a genus of Lower Cambrian Eodiscinid trilobite belonging to the family Weymouthiidae Kobayashi (1943) [3] Order Agnostida (Salter 1864) [4] It lived during the Botomian stage,[1] = late Lower Cambrian Stage 4 (upper of two stages subdividing the un-named Series 2); the upper Botomian Stage boundary corresponds to base of both the Middle Cambrian Wuliuan stage and Miaolingian Series.

Stigmadiscus resembles Acidiscus in having a relatively short glabella, distinct S1 and S2 lateral furrows, and a slender occipital spine. In fact, according to Cotton & Fortey (2005, fig. 3) [5] consensus is that Stigmadiscus and Bolboparia Rasetti, 1966, are sister taxa of Acidiscus.

  1. ^ a b SEPKOSKI, J. (2002). "A compendium of fossil marine animal genera (Trilobita entry)". Bulletins of American Paleontology. 364: 560. Archived from the original on September 5, 2006. Retrieved 2008-01-12.
  2. ^ RASETTI, F. (1966). "New Lower Cambrian trilobite faunule from the Taconic sequence of New York". Smithsonian Miscellaneous Collections. 148 (9): 1–52.
  3. ^ KOBAYASHI T. 1943. Brief notes on the Eodiscids 1, their classification with a description of a new species and a new variety, Proceedings of the Imperial Academy, Tokyo, Volume 19, pp. 37-42.
  4. ^ SALTER, J. W. 1864: On some new fossils from the Lingula - flags of Wales. Quarterly Journal of the Geological Society of London, 20, 233 – 241.
  5. ^ COTTON, T. J. and FORTEY, R. A. (2005). "5. Comparative morphology and relationships of the Agnostida". In Koenemann, S.; Jenner, R. (eds.). Crustacean Issues 16, Crustacea and Arthropod Relationships. Boca Raton: CRC Press.