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{{Infobox rockunit|name=Coalbrookdale Formation|map_caption=<!----Location---->|country_ts=<!--Country of type section-->|region_ts=<!--Region of type section-->|paleocoordinates_ts={{Coord|52|25|N|3|00|W|display=inline}}|coordinates_ts={{Coord|52|25|N|3|00|W||display=inline}}|location_ts=<!--Place,mountain,...-->|year_ts=<!--Year of definition-->|namedby=<!--Author of defining paper-->|namedfor=[[Coalbrookdale]]|extent={{Convert|5.2|mi|km}}
{{Infobox rockunit|name=Coalbrookdale Formation|map_caption=<!----Location---->|country_ts=<!--Country of type section-->|region_ts=<!--Region of type section-->|paleocoordinates_ts={{Coord|52|25|N|3|00|W|display=inline}}|coordinates_ts={{Coord|52|25|N|3|00|W||display=inline}}|location_ts=<!--Place,mountain,...-->|year_ts=<!--Year of definition-->|namedby=<!--Author of defining paper-->|namedfor=[[Coalbrookdale]]|extent={{Convert|5.2|mi|km}}
<!--Type section--->|country=[[United Kingdom]]|region=[[Powys]] and [[Herefordshire]]|coordinates={{Coord|52|25|N|3|00|W|display=title, inline|region:GB_type:adm1st_source:GNS-enwiki}}|location=[[England–Wales border]]|map=|period=Silurian|area=multiple {{convert|10000|km2|sqmi|abbr=on}}|thickness={{convert|192–265|m|ft|abbr=on}}|overlies=[[Much Wenlock Limestone Formation]]|underlies=[[Buildwas Formation]]|subunits=|unitof=|otherlithology=[[Limestone]]|prilithology=[[Mudstone]]|type=[[Geological formation]]|caption=|imagesize=|image=|age=Homerian<br>{{fossil range|430}}|thickness_ts=<!--Thickness at type section-->}}
<!--Type section--->|country=[[United Kingdom]]|region=[[Powys]] and [[Herefordshire]]|coordinates={{Coord|52|25|N|3|00|W|display=title, inline|region:GB_type:adm1st_source:GNS-enwiki}}|location=[[England–Wales border]]|map=|period=Silurian|area=multiple {{convert|10000|km2|sqmi|abbr=on}}|thickness={{convert|192–265|m|ft|abbr=on}}|overlies=[[Much Wenlock Limestone Formation]]|underlies=[[Buildwas Formation]]|subunits=|unitof=|otherlithology=[[Limestone]]|prilithology=[[Mudstone]]|type=[[Geological formation]]|caption=|imagesize=|image=|age=Homerian<br>{{fossil range|430}}|thickness_ts=<!--Thickness at type section-->}}
'''Coalbrookdale Formation''', earlier known as '''Wenlock Shale''' or '''Wenlock Shale Formation'''<ref>{{Cite journal|last=Davis|first=James Edward|date=1850|title=On the Age and Position of the Limestone of Nash, near Presteign, South Wales|url=https://jgs.lyellcollection.org/content/6/1-2/432|journal=Quarterly Journal of the Geological Society|language=en|volume=6|issue=1-2|pages=432–439|doi=10.1144/GSL.JGS.1850.006.01-02.48|issn=0370-291X}}</ref><ref>{{Cite web|title=Coalbrookdale Formation|url=https://data.bgs.ac.uk/id/Lexicon/NamedRockUnit/CBRD|url-status=live|website=British Geological Survey}}</ref> and also referred to as '''Herefordshire Lagerstätte''' in palaeontology,<ref>{{Cite journal|last=Siveter|first=David|date=2008|title=The Silurian Herefordshire Konservat-Lagerstätte: a unique window on the evolution of life|url=http://www.shropshiregeology.org.uk/sgspublications/Proceedings/2008%20No_13%20009%20Siveter%20Lagerstatte.pdf|journal=Proceedings of the Shropshire Geological Society|volume=13|pages=83-88}}</ref> is a fossil-rich deposit in Herefordshire at the [[England–Wales border]] in UK. It belongs to the [[Wenlock Series]] of the [[Silurian Period]] within the [[Homerian|Homerian Age]] (about 430 million years ago). It is known for its well-preserved fossils, many of which are in their three-dimensional structures, of various [[Invertebrate|invertebrate animals]]. Some of the fossils are regarded as earliest evidences and evolutionary origin of some of the major groups of animals.<ref>{{Cite journal|last=Siveter|first=Derek J.|last2=Briggs|first2=Derek E. G.|last3=Siveter|first3=David J.|last4=Sutton|first4=Mark D.|date=2020|title=The Herefordshire Lagerstätte: fleshing out Silurian marine life|url=https://jgs.lyellcollection.org/content/177/1/1|journal=Journal of the Geological Society|language=en|volume=177|issue=1|pages=1–13|doi=10.1144/jgs2019-110|issn=0016-7649}}</ref>
'''Coalbrookdale Formation''', earlier known as '''Wenlock Shale''' or '''Wenlock Shale Formation'''<ref>{{Cite journal|last=Davis|first=James Edward|date=1850|title=On the Age and Position of the Limestone of Nash, near Presteign, South Wales|url=https://jgs.lyellcollection.org/content/6/1-2/432|journal=Quarterly Journal of the Geological Society|language=en|volume=6|issue=1-2|pages=432–439|doi=10.1144/GSL.JGS.1850.006.01-02.48|issn=0370-291X}}</ref><ref>{{Cite web|title=Coalbrookdale Formation|url=https://data.bgs.ac.uk/id/Lexicon/NamedRockUnit/CBRD|url-status=live|website=British Geological Survey}}</ref> and also referred to as '''Herefordshire Lagerstätte''' in palaeontology,<ref name=":1">{{Cite journal|last=Siveter|first=David|date=2008|title=The Silurian Herefordshire Konservat-Lagerstätte: a unique window on the evolution of life|url=http://www.shropshiregeology.org.uk/sgspublications/Proceedings/2008%20No_13%20009%20Siveter%20Lagerstatte.pdf|journal=Proceedings of the Shropshire Geological Society|volume=13|pages=83-88}}</ref> is a fossil-rich deposit in Powys and Herefordshire at the [[England–Wales border]] in UK. It belongs to the [[Wenlock Series]] of the [[Silurian Period]] within the [[Homerian|Homerian Age]] (about 430 million years ago). It is known for its well-preserved fossils, many of which are in their three-dimensional structures, of various [[Invertebrate|invertebrate animals]]. Some of the fossils are regarded as earliest evidences and evolutionary origin of some of the major groups of animals.<ref name=":4">{{Cite journal|last=Siveter|first=Derek J.|last2=Briggs|first2=Derek E. G.|last3=Siveter|first3=David J.|last4=Sutton|first4=Mark D.|date=2020|title=The Herefordshire Lagerstätte: fleshing out Silurian marine life|url=https://jgs.lyellcollection.org/content/177/1/1|journal=Journal of the Geological Society|language=en|volume=177|issue=1|pages=1–13|doi=10.1144/jgs2019-110|issn=0016-7649}}</ref>

== History ==
[[Roderick Murchison]], at the time Vice-President both of the [[Geological Society]] and the Geographical Society of London (later [[Royal Geographic Society]]), was the first geologist to systematically investigate the Coalbrookdale Formation and the nearby regions including [[Herefordshire]], [[Shropshire]], [[Brecknockshire]], [[Radnorshire]], [[Monmouthshire]], and [[Carmarthenshire]] in the early 1930s.<ref>{{Cite journal|last=Secord|first=James A.|date=1982|title=King of Siluria: Roderick Murchison and the Imperial Theme in Nineteenth-Century British Geology|url=https://www.jstor.org/stable/3826980|journal=Victorian Studies|volume=25|issue=4|pages=413–442|issn=0042-5222|jstor=3826980}}</ref> In 1935, he named the sedimentary sequences "Silurian" for a [[Celts|Celtic]] tribe of Wales, the [[Silures]], inspired by his friend [[Adam Sedgwick]], who had named the period of his study the [[Cambrian]], from the [[Latin]] name for Wales.<ref>See:

* {{cite journal|last1=Murchison|first1=Roderick Impey|date=1835|title=On the Silurian system of rocks|url=https://babel.hathitrust.org/cgi/pt?id=umn.31951d01457537j&view=1up&seq=60|journal=Philosophical Magazine|series=3rd series|volume=7|issue=37|pages=46–52|doi=10.1080/14786443508648654}} From p. 48: " … I venture to suggest, that as the great mass of rocks in question, trending from south-west to north-east, traverses the kingdom of our ancestors the Silures, the term "Silurian system" should be adopted … "
* {{cite book|last1=Wilmarth|first1=Mary Grace|url=https://books.google.com/books?id=my7x_PBkpm4C&pg=PA80|title=Bulletin 769: The Geologic Time Classification of the United States Geological Survey Compared With Other Classifications, accompanied by the original definitions of era, period and epoch terms|date=1925|publisher=U.S. Government Printing Office|location=Washington, D.C., U.S.A.|page=80}}</ref> The same year, the two men presented a joint paper, under the title "On the Silurian and Cambrian Systems, Exhibiting the Order in which the Older Sedimentary Strata Succeed each other in England and Wales"'',<ref>{{cite journal|last1=Sedgwick|first=A.|last2=Murchison|first2=R.I.|date=1835|title=On the Silurian and Cambrian systems, exhibiting the order in which the older sedimentary strata succeed each other in England and Wales|url=https://www.biodiversitylibrary.org/item/252891#page/397/mode/1up|journal=Report of the Fifth Meeting of the British Association for the Advancement of Science. § Notices and Abstracts of Miscellaneous Communications to the Sections.|volume=5|pages=59–61}}</ref>'' which was the foundation of the modern [[Geologic time scale|geological time scale]].<ref>{{Cite journal|last=Mckerrow|first=W. S.|date=1993|title=The development of Early Palaeozoic global stratigraphy|url=https://jgs.lyellcollection.org/content/150/1/21|journal=Journal of the Geological Society|language=en|volume=150|issue=1|pages=21–28|doi=10.1144/gsjgs.150.1.0021|issn=0016-7649}}</ref><ref>{{Cite journal|last=Cope|first=J. C. W.|date=1996|title=The role of the Secondary Standard in stratigraphy|url=https://www.cambridge.org/core/journals/geological-magazine/article/abs/role-of-the-secondary-standard-in-stratigraphy/075A374C2D5A1ED57A0A9C874857C911|journal=Geological Magazine|language=en|volume=133|issue=1|pages=107–110|doi=10.1017/S0016756800007299|issn=1469-5081}}</ref>

In 1978, John M. Hurst, N. J. Hancock and William Stuart McKerrow determined the geological setting as [[Wenlock Group]] based on the distribution of [[brachiopod]] fossils.<ref>{{Cite journal|last=Hurst|first=J. M.|last2=Hancock|first2=N. J.|last3=McKerrow|first3=W. S.|date=1978|title=Wenlock stratigraphy and palaeogeography of Wales and the Welsh Borderland|url=https://www.sciencedirect.com/science/article/pii/S0016787878800121|journal=Proceedings of the Geologists' Association|language=en|volume=89|issue=3|pages=197–226|doi=10.1016/S0016-7878(78)80012-1|issn=0016-7878}}</ref>

== Geology ==
The Coalbrookdale Formation is located in an area in the southeastern part of Wales and southwestern part of England, covering the [[England–Wales border]] at Powys and Herefordshire. It lies above the [[Buildwas Formation]] and [[Woolhope Limestone]] that were deposited during the early Wenlock ([[Sheinwoodian]]). It was formed during Homerian under shallow water spreading from the Welsh border eastwards to the Midlands (in Herefordshire). The thickness ranges from 10 m up to 255 m. Above it is the [[Much Wenlock Limestone Formation]].<ref>{{Cite book|last=Cherns|first=Lesley|url=https://books.google.com/books?id=-6gqvAbdS-MC&newbks=0&printsec=frontcover&pg=PA92&dq=Coalbrookdale+Formation&hl=en|title=The Geology of England and Wales|last2=Cocks|first2=L.R.M|last3=Davies|first3=J.R.|last4=Hillier|first4=R.D.|last5=Waters|first5=R.A.|last6=Williams|first6=M.|date=2006|publisher=Geological Society of London|isbn=978-1-86239-200-7|editor-last=Brenchley|editor-first=P.J|edition=2|pages=91–92|language=en|editor-last2=Rawson|editor-first2=P.J.}}</ref>

== Biota and importance ==
The Coalbrookdale Formation represents one of the best evidences of Silurian life worldwide. In palaeontology, it is variedly referred to as Herefordshire biota,<ref name=":5">{{Cite book|last=Martinetto|first=Edoardo|url=https://books.google.com/books?id=Mo7zDwAAQBAJ&newbks=0&printsec=frontcover&pg=PA361&dq=herefordshire+lagerstatte&hl=en|title=Nature through Time: Virtual Field Trips through the Nature of the Past|last2=Tschopp|first2=Emanuel|last3=Gastaldo|first3=Robert A.|date=2020|publisher=Springer Nature|isbn=978-3-030-35058-1|pages=361–362|language=en}}</ref><ref>{{Cite journal|last=Orr|first=Patrick J.|last2=Briggs|first2=Derek E. G.|last3=Siveter|first3=David J.|last4=Siveter|first4=Derek J.|date=2000|title=Three‐dimensional preservation of a non‐biomineralized arthropod in concretions in Silurian volcaniclastic rocks from Herefordshire, England|url=https://jgs.lyellcollection.org/content/157/1/173|journal=Journal of the Geological Society|language=en|volume=157|issue=1|pages=173–186|doi=10.1144/jgs.157.1.173|issn=0016-7649}}</ref> Herefordshire Nodules,<ref>{{Citation|last=Selden|first=Paul|title=The Herefordshire Nodules|date=2012|url=https://www.taylorfrancis.com/chapters/mono/10.1201/b15128-10/herefordshire-nodules-paul-selden-john-nudds|work=Evolution of Fossil Ecosystems|pages=53–62|edition=2|publisher=CRC Press|doi=10.1201/b15128-10/herefordshire-nodules-paul-selden-john-nudds|isbn=978-0-429-15921-3|access-date=2022-01-11|last2=Nudds|first2=John}}</ref><ref name=":6">{{Cite book|last=Carlton|first=Robert L.|url=https://books.google.com/books?id=9MK3DwAAQBAJ&newbks=0&printsec=frontcover&pg=PA191&dq=%22Herefordshire+Nodules%22&hl=en|title=A Concise Dictionary of Paleontology: Second Edition|date=2019|publisher=Springer Nature|isbn=978-3-030-25586-2|pages=191|language=en}}</ref> and Herefordshire Lagerstätte.<ref name=":1" /><ref>{{Cite journal|last=Carter|first=Reece P.|last2=Sutton|first2=Mark D.|last3=Briggs|first3=Derek E. G.|last4=Rahman|first4=Imran A.|last5=Siveter|first5=David J.|last6=Siveter|first6=Derek J.|date=2021|title=A Silurian ophiuroid with soft-tissue preservation|url=https://onlinelibrary.wiley.com/doi/abs/10.1002/spp2.1390|journal=Papers in Palaeontology|language=en|volume=7|issue=4|pages=2041–2047|doi=10.1002/spp2.1390|issn=2056-2802}}</ref> A variety of extinct animals have been recovered and described from it, including [[arthropods]], [[polychaete]] worms, [[sponges]], [[Mollusca|mollusks,]] [[echinoderms]], [[lobopods]] and several unassigned specimens.<ref name=":4" /><ref name=":6">{{Cite book|last=Carlton|first=Robert L.|url=https://books.google.com/books?id=9MK3DwAAQBAJ&newbks=0&printsec=frontcover&pg=PA191&dq=%22Herefordshire+Nodules%22&hl=en|title=A Concise Dictionary of Paleontology: Second Edition|date=2019|publisher=Springer Nature|isbn=978-3-030-25586-2|pages=191|language=en}}</ref> The uniqness of the fossil assemblage is that it is not only diverse, but also preserved in three-dimensional structure, from which more details of the animal appearances could be deciphered.<ref name=":5">{{Cite book|last=Martinetto|first=Edoardo|url=https://books.google.com/books?id=Mo7zDwAAQBAJ&newbks=0&printsec=frontcover&pg=PA361&dq=herefordshire+lagerstatte&hl=en|title=Nature through Time: Virtual Field Trips through the Nature of the Past|last2=Tschopp|first2=Emanuel|last3=Gastaldo|first3=Robert A.|date=2020|publisher=Springer Nature|isbn=978-3-030-35058-1|pages=361–362|language=en}}</ref>

=== Notable animals ===

# ''Colymbosathon ecplecticos'' is an extinct shrimp ([[ostracod]]). Discovered in 2003, its obvious similarity with living shrimps shows that the ostracods have retained much of their structure through millions of years. The name means "the astounding swimmer with a large penis."<ref name=":5">{{Cite book|last=Martinetto|first=Edoardo|url=https://books.google.com/books?id=Mo7zDwAAQBAJ&newbks=0&printsec=frontcover&pg=PA361&dq=herefordshire+lagerstatte&hl=en|title=Nature through Time: Virtual Field Trips through the Nature of the Past|last2=Tschopp|first2=Emanuel|last3=Gastaldo|first3=Robert A.|date=2020|publisher=Springer Nature|isbn=978-3-030-35058-1|pages=361–362|language=en}}</ref>
# ''Enalikter aphson'' is one of the animals of unknown identity. Although it was originally classified as an arthropod in 2015, later reanalysis showed that it may have more affinity towards the polychaete worms.<ref name=":5">{{Cite book|last=Martinetto|first=Edoardo|url=https://books.google.com/books?id=Mo7zDwAAQBAJ&newbks=0&printsec=frontcover&pg=PA361&dq=herefordshire+lagerstatte&hl=en|title=Nature through Time: Virtual Field Trips through the Nature of the Past|last2=Tschopp|first2=Emanuel|last3=Gastaldo|first3=Robert A.|date=2020|publisher=Springer Nature|isbn=978-3-030-35058-1|pages=361–362|language=en}}</ref>
# ''Heliesta dasos'' is a type of [[sea spider]] (arthropod) described in 2004. Sea spider fossils are rare so that this specimen is attributed to one of the earliest species from which later sea spiders evolved.<ref name=":5">{{Cite book|last=Martinetto|first=Edoardo|url=https://books.google.com/books?id=Mo7zDwAAQBAJ&newbks=0&printsec=frontcover&pg=PA361&dq=herefordshire+lagerstatte&hl=en|title=Nature through Time: Virtual Field Trips through the Nature of the Past|last2=Tschopp|first2=Emanuel|last3=Gastaldo|first3=Robert A.|date=2020|publisher=Springer Nature|isbn=978-3-030-35058-1|pages=361–362|language=en}}</ref>
# ''[[Sollasina cthulhu]]'' is an extinct echinoderm described in 2019.<ref name="rahman19">{{cite journal|last1=Rahman|first1=Imran A.|last2=Thompson|first2=Jeffrey R.|last3=Briggs|first3=Derek E. G.|last4=Siveter|first4=David J.|last5=Siveter|first5=Derek J.|last6=Sutton|first6=Mark D.|year=2019|title=A new ophiocistioid with soft-tissue preservation from the Silurian Herefordshire Lagerstätte, and the evolution of the holothurian body plan|journal=Proceedings of the Royal Society B|volume=286|issue=1900|pages=20182792|doi=10.1098/rspb.2018.2792|pmc=6501687|pmid=30966985}}</ref> The scientifica name is given because of its somewhat resemblance to [[Cthulhu Mythos]], a fictional charcater created by [[H.P. Lovecraft]].<ref>{{cite web|last1=Shelton|first1=Jim|date=2019-04-11|title=Researchers Discover Fossils of Cthulhu-Like Creature|url=https://scitechdaily.com/researchers-discover-fossils-of-cthulhu-like-creature/|website=Scitech Daily|accessdate=13 April 2019}}</ref>
# ''[[Thanahita distos]]'' is an extinct lobopod discovered in 2018.<ref name=":0">{{Cite journal|last=Siveter|first=Derek J.|last2=Briggs|first2=Derek E. G.|last3=Siveter|first3=David J.|last4=Sutton|first4=Mark D.|last5=Legg|first5=David|date=2018|title=A three-dimensionally preserved lobopodian from the Herefordshire (Silurian) Lagerstätte, UK|url=https://royalsocietypublishing.org/doi/full/10.1098/rsos.172101|journal=Royal Society Open Science|volume=5|issue=8|pages=172101|doi=10.1098/rsos.172101|pmc=6124121|pmid=30224988}}</ref> It is the first Silurian lobopod known worldwide.<ref name=":2">{{Cite web|date=2018-08-08|title=New species of rare ancient ‘worm’ discovered in fossil hotspot {{!}} University of Oxford|url=https://www.ox.ac.uk/news/2018-08-08-new-species-rare-ancient-%E2%80%98worm%E2%80%99-discovered-fossil-hotspot|url-status=live|access-date=2022-01-07|website=www.ox.ac.uk|language=en}}</ref><ref name=":3">{{Cite web|last=Shelton|first=Jim|date=2018-08-09|title=Researchers discover Silurian relative of the Cambrian lobopod Hallucigenia|url=https://news.yale.edu/2018/08/09/researchers-discover-silurian-relative-cambrian-lobopod-hallucigenia|access-date=2022-01-07|website=YaleNews|language=en}}</ref> Lobopods emerged during Cambrian explosion and they are believed to be ancestors of modern arthropods, [[velvet worms]] and [[tardigrades]].<ref>{{Cite journal|last1=Caron|first1=Jean-Bernard|last2=Aria|first2=Cédric|date=2017|title=Cambrian suspension-feeding lobopodians and the early radiation of panarthropods|url=https://doi.org/10.1186/s12862-016-0858-y|journal=BMC Evolutionary Biology|volume=17|issue=1|pages=29|doi=10.1186/s12862-016-0858-y|pmc=5282736|pmid=28137244}}</ref>


== References ==
== References ==

Revision as of 12:17, 11 January 2022

Coalbrookdale Formation
Stratigraphic range: Homerian
430 Ma
↓
TypeGeological formation
UnderliesBuildwas Formation
OverliesMuch Wenlock Limestone Formation
Areamultiple 10,000 km2 (3,900 sq mi)
Thickness192–265 m (630–869 ft)
Lithology
PrimaryMudstone
OtherLimestone
Location
LocationEngland–Wales border
Coordinates52°25′N 3°00′W / 52.417°N 3.000°W / 52.417; -3.000
RegionPowys and Herefordshire
CountryUnited Kingdom
Extent5.2 miles (8.4 km)
Type section
Named forCoalbrookdale
Coordinates52°25′N 3°00′W / 52.417°N 3.000°W / 52.417; -3.000
Approximate paleocoordinates52°25′N 3°00′W / 52.417°N 3.000°W / 52.417; -3.000

Coalbrookdale Formation, earlier known as Wenlock Shale or Wenlock Shale Formation[1][2] and also referred to as Herefordshire Lagerstätte in palaeontology,[3] is a fossil-rich deposit in Powys and Herefordshire at the England–Wales border in UK. It belongs to the Wenlock Series of the Silurian Period within the Homerian Age (about 430 million years ago). It is known for its well-preserved fossils, many of which are in their three-dimensional structures, of various invertebrate animals. Some of the fossils are regarded as earliest evidences and evolutionary origin of some of the major groups of animals.[4]

History

Roderick Murchison, at the time Vice-President both of the Geological Society and the Geographical Society of London (later Royal Geographic Society), was the first geologist to systematically investigate the Coalbrookdale Formation and the nearby regions including Herefordshire, Shropshire, Brecknockshire, Radnorshire, Monmouthshire, and Carmarthenshire in the early 1930s.[5] In 1935, he named the sedimentary sequences "Silurian" for a Celtic tribe of Wales, the Silures, inspired by his friend Adam Sedgwick, who had named the period of his study the Cambrian, from the Latin name for Wales.[6] The same year, the two men presented a joint paper, under the title "On the Silurian and Cambrian Systems, Exhibiting the Order in which the Older Sedimentary Strata Succeed each other in England and Wales",[7] which was the foundation of the modern geological time scale.[8][9]

In 1978, John M. Hurst, N. J. Hancock and William Stuart McKerrow determined the geological setting as Wenlock Group based on the distribution of brachiopod fossils.[10]

Geology

The Coalbrookdale Formation is located in an area in the southeastern part of Wales and southwestern part of England, covering the England–Wales border at Powys and Herefordshire. It lies above the Buildwas Formation and Woolhope Limestone that were deposited during the early Wenlock (Sheinwoodian). It was formed during Homerian under shallow water spreading from the Welsh border eastwards to the Midlands (in Herefordshire). The thickness ranges from 10 m up to 255 m. Above it is the Much Wenlock Limestone Formation.[11]

Biota and importance

The Coalbrookdale Formation represents one of the best evidences of Silurian life worldwide. In palaeontology, it is variedly referred to as Herefordshire biota,[12][13] Herefordshire Nodules,[14][15] and Herefordshire Lagerstätte.[3][16] A variety of extinct animals have been recovered and described from it, including arthropods, polychaete worms, sponges, mollusks, echinoderms, lobopods and several unassigned specimens.[4][15] The uniqness of the fossil assemblage is that it is not only diverse, but also preserved in three-dimensional structure, from which more details of the animal appearances could be deciphered.[12]

Notable animals

  1. Colymbosathon ecplecticos is an extinct shrimp (ostracod). Discovered in 2003, its obvious similarity with living shrimps shows that the ostracods have retained much of their structure through millions of years. The name means "the astounding swimmer with a large penis."[12]
  2. Enalikter aphson is one of the animals of unknown identity. Although it was originally classified as an arthropod in 2015, later reanalysis showed that it may have more affinity towards the polychaete worms.[12]
  3. Heliesta dasos is a type of sea spider (arthropod) described in 2004. Sea spider fossils are rare so that this specimen is attributed to one of the earliest species from which later sea spiders evolved.[12]
  4. Sollasina cthulhu is an extinct echinoderm described in 2019.[17] The scientifica name is given because of its somewhat resemblance to Cthulhu Mythos, a fictional charcater created by H.P. Lovecraft.[18]
  5. Thanahita distos is an extinct lobopod discovered in 2018.[19] It is the first Silurian lobopod known worldwide.[20][21] Lobopods emerged during Cambrian explosion and they are believed to be ancestors of modern arthropods, velvet worms and tardigrades.[22]

References

  1. ^ Davis, James Edward (1850). "On the Age and Position of the Limestone of Nash, near Presteign, South Wales". Quarterly Journal of the Geological Society. 6 (1–2): 432–439. doi:10.1144/GSL.JGS.1850.006.01-02.48. ISSN 0370-291X.
  2. ^ "Coalbrookdale Formation". British Geological Survey.{{cite web}}: CS1 maint: url-status (link)
  3. ^ a b Siveter, David (2008). "The Silurian Herefordshire Konservat-Lagerstätte: a unique window on the evolution of life" (PDF). Proceedings of the Shropshire Geological Society. 13: 83–88.
  4. ^ a b Siveter, Derek J.; Briggs, Derek E. G.; Siveter, David J.; Sutton, Mark D. (2020). "The Herefordshire Lagerstätte: fleshing out Silurian marine life". Journal of the Geological Society. 177 (1): 1–13. doi:10.1144/jgs2019-110. ISSN 0016-7649.
  5. ^ Secord, James A. (1982). "King of Siluria: Roderick Murchison and the Imperial Theme in Nineteenth-Century British Geology". Victorian Studies. 25 (4): 413–442. ISSN 0042-5222. JSTOR 3826980.
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  7. ^ Sedgwick, A.; Murchison, R.I. (1835). "On the Silurian and Cambrian systems, exhibiting the order in which the older sedimentary strata succeed each other in England and Wales". Report of the Fifth Meeting of the British Association for the Advancement of Science. § Notices and Abstracts of Miscellaneous Communications to the Sections. 5: 59–61.
  8. ^ Mckerrow, W. S. (1993). "The development of Early Palaeozoic global stratigraphy". Journal of the Geological Society. 150 (1): 21–28. doi:10.1144/gsjgs.150.1.0021. ISSN 0016-7649.
  9. ^ Cope, J. C. W. (1996). "The role of the Secondary Standard in stratigraphy". Geological Magazine. 133 (1): 107–110. doi:10.1017/S0016756800007299. ISSN 1469-5081.
  10. ^ Hurst, J. M.; Hancock, N. J.; McKerrow, W. S. (1978). "Wenlock stratigraphy and palaeogeography of Wales and the Welsh Borderland". Proceedings of the Geologists' Association. 89 (3): 197–226. doi:10.1016/S0016-7878(78)80012-1. ISSN 0016-7878.
  11. ^ Cherns, Lesley; Cocks, L.R.M; Davies, J.R.; Hillier, R.D.; Waters, R.A.; Williams, M. (2006). Brenchley, P.J; Rawson, P.J. (eds.). The Geology of England and Wales (2 ed.). Geological Society of London. pp. 91–92. ISBN 978-1-86239-200-7.
  12. ^ a b c d e Martinetto, Edoardo; Tschopp, Emanuel; Gastaldo, Robert A. (2020). Nature through Time: Virtual Field Trips through the Nature of the Past. Springer Nature. pp. 361–362. ISBN 978-3-030-35058-1.
  13. ^ Orr, Patrick J.; Briggs, Derek E. G.; Siveter, David J.; Siveter, Derek J. (2000). "Three‐dimensional preservation of a non‐biomineralized arthropod in concretions in Silurian volcaniclastic rocks from Herefordshire, England". Journal of the Geological Society. 157 (1): 173–186. doi:10.1144/jgs.157.1.173. ISSN 0016-7649.
  14. ^ Selden, Paul; Nudds, John (2012), "The Herefordshire Nodules", Evolution of Fossil Ecosystems (2 ed.), CRC Press, pp. 53–62, doi:10.1201/b15128-10/herefordshire-nodules-paul-selden-john-nudds, ISBN 978-0-429-15921-3, retrieved 2022-01-11
  15. ^ a b Carlton, Robert L. (2019). A Concise Dictionary of Paleontology: Second Edition. Springer Nature. p. 191. ISBN 978-3-030-25586-2.
  16. ^ Carter, Reece P.; Sutton, Mark D.; Briggs, Derek E. G.; Rahman, Imran A.; Siveter, David J.; Siveter, Derek J. (2021). "A Silurian ophiuroid with soft-tissue preservation". Papers in Palaeontology. 7 (4): 2041–2047. doi:10.1002/spp2.1390. ISSN 2056-2802.
  17. ^ Rahman, Imran A.; Thompson, Jeffrey R.; Briggs, Derek E. G.; Siveter, David J.; Siveter, Derek J.; Sutton, Mark D. (2019). "A new ophiocistioid with soft-tissue preservation from the Silurian Herefordshire Lagerstätte, and the evolution of the holothurian body plan". Proceedings of the Royal Society B. 286 (1900): 20182792. doi:10.1098/rspb.2018.2792. PMC 6501687. PMID 30966985.
  18. ^ Shelton, Jim (2019-04-11). "Researchers Discover Fossils of Cthulhu-Like Creature". Scitech Daily. Retrieved 13 April 2019.
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  20. ^ "New species of rare ancient 'worm' discovered in fossil hotspot | University of Oxford". www.ox.ac.uk. 2018-08-08. Retrieved 2022-01-07.{{cite web}}: CS1 maint: url-status (link)
  21. ^ Shelton, Jim (2018-08-09). "Researchers discover Silurian relative of the Cambrian lobopod Hallucigenia". YaleNews. Retrieved 2022-01-07.
  22. ^ Caron, Jean-Bernard; Aria, Cédric (2017). "Cambrian suspension-feeding lobopodians and the early radiation of panarthropods". BMC Evolutionary Biology. 17 (1): 29. doi:10.1186/s12862-016-0858-y. PMC 5282736. PMID 28137244.{{cite journal}}: CS1 maint: unflagged free DOI (link)
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