Ptychagnostus atavus

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Ptychagnostus atavus
Temporal range: Drumian
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Ptychagnostus Atavus.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Trilobita (?)
Order: Agnostida
Family: Ptychagnostidae
Genus: Ptychagnostus
Species:
P. atavus
Binomial name
Ptychagnostus atavus
Synonyms
  • Acidusus atavus(Tullberg, 1880)
  • Agnostus atavusTullberg 1880

Ptychagnostus atavus is a species of agnostid trilobite. It was originally described by Swedish paleontologist Sven Axel Tullberg as Agnostus atavus in 1880. [1] It is used in biostratigraphy as an index fossil. Its first appearance at the GSSP section in the Wheeler Shale of Utah is defined as the beginning of the Drumian Age (around 504.5 million years ago) of the Miaolingian (Middle Cambrian). [2] [3]

Laurie (2008) [4] grouped punctuosus and affinis within Ptychagnostus, but preferred to place the closely related atavus within Acidusus.

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<i>Agraulos</i> Genus of trilobites

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<span class="mw-page-title-main">Wheeler Shale</span> Geologic formation in Utah notable for trilobite fossils

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<i>Pagetia</i> Genus of trilobites

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<i>Ptychagnostus</i> Extinct genus of trilobites

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<span class="mw-page-title-main">Marjum Formation</span>

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<i>Glyptagnostus reticulatus</i> Extinct species of trilobite

Glyptagnostus reticulatus is a species of agnostid trilobite belonging to the genus Glyptagnostus. It existed during the Paibian Age of the Cambrian. It has a cosmopolitan distribution and is an important index fossil in biostratigraphy. It was characterized by an unusual net-like pattern of furrows on both the cephalon and the pygidium.

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<span class="mw-page-title-main">Peronopsidae</span>

The Peronopsidae comprise the earliest family of the Agnostina suborder. Species of this family occurred on all paleocontinents. The earliest representatives of this family first occur just before the start of the Middle Cambrian, and the last disappeared just after the start of the Upper Cambrian.

<i>Itagnostus</i>

Itagnostus is a genus of trilobite restricted to the Middle Cambrian. Its remains have been found in Asia, Australia, Europe, and North America.

<i>Condylopyge</i>

Condylopyge Hawle and Corda (1847) is a genus of agnostid trilobite that lived during the late Lower and early Middle Cambrian, in what are today Canada, the Czech Republic, England and Wales, France, Germany, Italy, Morocco, the Russian Federation, Spain, Turkey and Sweden. It can easily be distinguished from all other Agnostida because the frontal glabellar lobe is notably wider than the rear lobe. It belongs to the same family as Pleuroctenium but the frontal glabellar lobe does not fold around the rear lobe, as it does in that genus. Condylopyge is long ranging, possibly spanning the early Cambrian Terreneuvian Series in Nuneaton, central England into at least Drumian strata at various locations elsewhere.

References

  1. "Ptychagnostus atavus". Paleobiology Database. Retrieved 16 November 2012.
  2. Babcock, L. E.; Robison, R. A.; Rees, M. N.; Peng, S.; Saltzman, M. R. (2007). "The Global boundary Stratotype Section and Point (GSSP) of the Drumian Stage (Cambrian) in the Drum Mountains, Utah, USA" (PDF). Episodes. 30 (2): 85–95. doi: 10.18814/epiiugs/2007/v30i2/003 .
  3. Ogg, G. "GSSP for Drumian Stage". Geologic TimeScale Foundation. Retrieved 16 November 2012.
  4. LAURIE J. R. 2008. Species relationships in the Ptychagnostidae (Cambrian, Agnostina). In: Ra´bano I., Gozalo R. & GarciaBellido D. eds. Advances in trilobite research, pp. 211–218. Cuadernos del Museo Geominero 9.