Condylopygidae

Condylopygidae

Condylopygidae

Family of trilobites


The Condylopygidae Raymond (2013) [2] are a family of small trilobites that lived during the Middle Cambrian, and found in Canada (Newfoundland and Nova Scotia), the Czech Republic, Germany, France, Spain, England, Wales, Sweden, and the Russian Federation (Siberia). They uniquely differ from all other Agnostina in having the frontal glabellar lobe wider than the rear lobe. The Condylopygidae are the only family assigned to the Condylopygoidea superfamily.

Quick Facts Scientific classification, genera ...

Taxonomy

The Condylopygoidea are an isolated branch in the Agnostina suborder that occur approximately contemporaneously with the Peronopsidae, the earliest representatives of the main branch of the Agnostina. One species, Peronopsis palmadon, appears intermediate between Peronopsidae and Condylopygidae, but it is not clear whether P. palmadon is ancestral to the Condylopygidae - a regression towards ancestral characters or an example of parallel evolution.[3]

Description

Drawing of Condylopyge cf regia explaining unique anatomic features

Like all Agnostida, members of the Condylopygidae are relatively small and isopygous with the cephalon and pygidium of approximately similar size and outline. The characteristic expansion of the glabellar frontal lobe, occipital structures instead of basal lobes, and pygidial axis with three pairs of side lobes and a posterior axial lobe differentiate Condylopygoidea from Agnostoidea. [4]

Key to the genera

More information - ...

References

  1. RUSHTON, A. W. A.; WEIDNER, T. (2007). "The Middle Cambrian paradoxidid trilobite Hydrocephalus from Jämtland, central Sweden" (PDF). Acta Geologica Polonica. 57 (4): 391–401. Retrieved 30 March 2013.
  2. RAYMOND, P. E., 1913: Some changes in the names of genera of trilobites. The Ottawa Naturalist, 26: 137−142.
  3. NAIMARK, E. B. (2012). "Hundred species of the Genus Peronopsis Hawle et Corda, 1847". Paleontological Journal. 46 (9): 945–1057. Bibcode:2012PalJ...46..945N. doi:10.1134/S0031030112090018. S2CID 85130465.
  4. WHITTINGTON, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997

Share this article:

This article uses material from the Wikipedia article Condylopygidae, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.