Asaphestera

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Asaphestera
Temporal range: Carboniferous, 318.1–314.6  Ma
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Asaphestera platyris.jpg
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Genus: Asaphestera
Steen, 1934
Type species
Asaphestera platyris
Steen, 1934

Asaphestera is an extinct genus of a tetrapod described on the basis of fossils from the Carboniferous of the Joggins locality in Nova Scotia, Canada. It was originally described as an undetermined lepospondyl [1] and subsequently classified as a microsaur within the family Tuditanidae. [2] A study published in May 2020 found that specimens referred to Asaphestera represented several unrelated species. Steen (1934)'s original species name Asaphestera platyris was retained for a skull which has been re-evaluated as the earliest known synapsid. [1] [3]

The type species of Asaphestera is Asaphestera platyris, named by Steen (1934) based on three skulls. Carroll & Gaskill (1978) noted that one of the skulls was briefly named as the species "Hylerpeton" intermedium by Dawson (1894), though it is no longer consider related to the genus Hylerpeton. According to Dawson's species name, they renamed Asaphestera platyris to Asaphestera intermedia. [4]

Mann et al. (2020) re-evaluated purported Joggins microsaurs and found several unusual results. One of the skulls assigned the name Asaphestera platyris by Steen appeared to be a valid taxon, but instead of a microsaur it was the oldest known synapsid, possibly an eothyridid. Dawson's "Hylerpeton" intermedium was determined to be an indeterminate tetrapod and a nomen dubium . Additional Asaphestera material was named as a new genus of microsaur, Steenerpeton . [3]

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Robert "Bob" Lynn Carroll was an American–Canadian vertebrate paleontologist who specialised in Paleozoic and Mesozoic amphibians and reptiles.

<span class="mw-page-title-main">Joggins</span> Community in Nova Scotia, Canada

Joggins is a rural community located in western Cumberland County, Nova Scotia, Canada. On July 7, 2008 a 15-km length of the coast constituting the Joggins Fossil Cliffs was officially inscribed on the World Heritage List.

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<i>Archaeothyris</i> Extinct genus of synapsids

Archaeothyris is an extinct genus of ophiacodontid synapsid that lived during the Late Carboniferous and is known from Nova Scotia. Dated to 306 million years ago, Archaeothyris, along with a more poorly known synapsid called Echinerpeton, are the oldest undisputed synapsids known. The name means ancient window (Greek), and refers to the opening in the skull, the temporal fenestra, which indicates this is an early synapsid. Protoclepsydrops also from Nova Scotia is slightly older but is known by very fragmentary materials.

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Carrolla is an extinct genus of brachystelechid 'microsaur' that lived in the Lower Permian in North America. It was named in 1986 by American paleontologists Wann Langston and Everett Olson. The type species, Carrolla craddocki, is the only known species.

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<i>Rhynchonkos</i> Extinct genus of amphibians

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

The Joggins Formation is a geologic formation in Nova Scotia. It preserves fossils dating back to the Carboniferous period, including Hylonomus, the earliest known reptile. In addition to fossils, the Joggins Formation was a valuable source of coal from the 17th century until the mid-20th century.

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References

  1. 1 2 Steen, Margaret C. (1934). "The amphibian fauna from the South Joggins. Nova Scotia". Journal of Zoology. 104 (3): 465–504. doi:10.1111/j.1096-3642.1934.tb01644.x.
  2. "†Asaphestera Steen 1934". Paleobiology Database. Fossilworks. Retrieved 17 December 2021.
  3. 1 2 Mann, Arjan; Gee, Bryan M.; Pardo, Jason D.; Marjanović, David; Adams, Gabrielle R.; Calthorpe, Ami S.; Maddin, Hillary C.; Anderson, Jason S. (5 May 2020). Sansom, Robert (ed.). "Reassessment of historic 'microsaurs' from Joggins, Nova Scotia, reveals hidden diversity in the earliest amniote ecosystem". Papers in Palaeontology. Wiley. doi:10.1002/spp2.1316. ISSN   2056-2802.
  4. Carroll, Robert L.; Gaskill, Pamela (1978). "The Order Microsauria". Memoirs of the American Philosophical Society. 126: 1–211.