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Quercy Phosphorites Formation

Coordinates: 44°18′N 1°36′E / 44.3°N 1.6°E / 44.3; 1.6
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Quercy Phosphorites Formation
Stratigraphic range: latest Bartonian-Late Oligocene
~38–25 Ma
TypeFormation
OverliesFissure fillings in karstified Jurassic and Triassic rocks
Lithology
PrimaryPhosphorite
Location
Coordinates44°18′N 1°36′E / 44.3°N 1.6°E / 44.3; 1.6
Approximate paleocoordinates42°48′N 2°00′W / 42.8°N 2.0°W / 42.8; -2.0
RegionOccitanie
CountryFrance
Type section
Named forQuercy
Named byThévenin
Year defined1903
Quercy Phosphorites Formation is located in France
Quercy Phosphorites Formation
Quercy Phosphorites Formation (France)

The Quercy Phosphorites Formation (French: Phosphorites du Quercy) is a geologic formation and lagerstätte in Occitanie, southern France. It preserves fossils dated to the Paleogene period (latest Bartonian to Late Oligocene),[1][2] or MP16 to MP28 zones of the European land mammal age classification, ranging from approximately 38 to 25 Ma.

It qualifies as a Lagerstätte because beside a large variety of mammals, birds, turtles, crocodiles, flora and insects, it also preserves the soft tissues of amphibians and squamates, in addition to their articulated skeleton in what has been called natural mummies.[3]

The genera Quercylurus, Quercymegapodius, Quercypsitta, Quercypodargus, Quercycerta and Quercygama, and species Mosaicomeryx quercyi, Robiacina quercyi, Palaeophyllophora quercyi, Archaeomys quercyi, Eomys quercyi, Eucricetodon quercyi and Tarnomys quercynus, as well as the lizards Paraplacosauriops quercyi and Pseudolacerta quercyini and the insect Palaeortona quercyensis were named after the formation.

Description

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The first phosphate deposits in Quercy were discovered in 1869 and published by Daubré and Trutat independently in 1871.[4] The first fossils from the formation were described by Delfortie (1872) and Gervais in the same year and extensively studied by Filhol from 1877 onwards. The first geologic investigation of the formation was performed by Thévenin in 1903, and apart from a description by Gèze in 1938, the paleontological richness was not studied until a team of researchers of the Universities of Montpellier and Paris visited the site in 1965.[5]

The karstified phosphate deposits are found from the Lot and Célé river valleys in the north to the left bank of the Aveyron in the south and from the Villefranche Fault in the east to the lacustrine deposits of the Aquitaine Basin in the west. The formation is found in fissures (karst) incising Jurassic and Triassic rocks east of Cahors.[6] The age of the fossiliferous unit, in which almost 12,000 specimens were found ranges from the MP16 to MP28 zones of the European land mammal age classification.[5] These ages correspond to the latest Bartonian to Chattian, from about 38 to 25 Ma.[7]

Paleontological significance

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Paleogeography of the Late Eocene to Oligocene with biodiversity of the Quercy Phosphorites
Exceptional preservation of nerves, digestive tract and stomachal content in the frog-eating salamander Phosphotriton sigei

The Quercy Phosphorites Formation is a highly fossiliferous unit designated as a Lagerstätte due to the excellent preservation of fossils. The phosphorite conserves up to the nerves, digestive tract and stomach content,[8] insect larvae and other elements of the paleobiology in the formation. Nearly all Quercy fly pupae were preserved as isolated endocasts, of which many were still covered by the puparium, the hardened skin of the last larval instar.[9] The formation also straddles the Grande Coupure and shows diversity changes (number of species) of frog, salamander, lizard and snake fossil records across the formation.[10] It is assumed that the Quercy arthropods fossilized by a rapid fixation by phosphate-rich water followed by encrustation and mineralization.[11]

Fossil content

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The following fossils have been reported from the formation:[1][2][12][13]

Mammals

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Apatemyidae
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Genus Species Location Stratigraphic position Material Note Images
Chardinyus C. sp.[12] An apatotheria.
Heterohyus H. (Chardinyus) nanus[12] An apatemyid.
H. (Gervaisyus) pygmaeus[12]
Gervaisyus G. sp.[12]
Artiodactyls
Genus Species Location Stratigraphic position Material Notes Images
Bachitherium B. guirounetensis[13]
B. lavocati[13]
Cryptomeryx C. gaudryi[14]
Dichobune D. sigei[13]
Dichodon D. vidalenci[13]
Iberomeryx I. matsoui[13]
Mosaicomeryx M. quercyi[15]
Paroxacron P. bergeri[16]
Plesiomeryx P. cadurcensis[16]
Prodremotherium P. elongatum[15]
Pseudamphimeryx P. salesmei[13]
Robiacina R. lavergnensis[13]
R. quercyi[13]
Tapirulus Tapirulus perrierensis[13]
Carnivora
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Genus Species Location Stratigraphic position Material Notes Images
Amphicynodon A. typicus[17]
Cephalogale C. sp.[18]
Cynodyctis C. lacustris neboulensis[13]
Dinailurictis D. bonali[19][20]
Eofelis E. edwardsii[21][22]
E. giganteus[23]
cf. E. sp.[24]
Eusmilus E. bidentatus[21][22]
Mustelictis M. cf. major[25]
M. aff. olivieri[25]
Nimravus N. intermedius[19][20]
Pachycynodon P. amphictina[26]
P. crassirostris[27]
P. cf. dubius[26]
P. cf. filholi[28]
Palaeogale P. sectoria[22]
Peignictis P. pseudamphictis[29]
Quercylurus Q. major[19]
Wangictis W. tedfordi[30]
Chiroptera
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Genus Species Location Stratigraphic position Material Notes Images
Hipposideros Pseudorhinolophus H. P. sehlosseri[12]
H. P. trassounius[12]
H. P. zbrjdi[12]
Leuconoe L. lavocati[12]
Palaeophyllophora P. oltina[12]
P. quercyi[12]
Stehlinia S. bonisi[12]
S. minor[12]
Vaylatsia V. garouillasensis[12]
V. gerscheli[12]
V. gracilis[12]
V. lapradensis[12]
Creodonta
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Genus Species Location Stratigraphic position Material Images
Paracynohyaenodon P. magnus[12]
Parapterodon P. lostangensis[12]
Euarchonta
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Genus Species Location Stratigraphic position Material Images
Darbonetus D. aubrelongensis[31]
Hyaenodonta
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Genus Species Location Stratigraphic position Material Notes Images
Paroxyaena P. pavlovi[32]
Lipotyphla
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Genus Species Location Stratigraphic position Material Notes Images
Amphidozotherium A. cayluxi[12]
Darbonetus D. aubrelongensis[12]
D. tuberi[12]
Myxomygale M. antiqua[33]
Saturninia S. beata[12]
S. pelissiei[12]
Marsupials
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Genus Species Location Stratigraphic position Material Notes Images
Amphiperatherium A. bourdellense[12]
A. lamandini[12]
Peratherium P. bretouense[12]
P. cayluxi[12]
P. lavergnense[12]
P. perrierense[12]
Perissodactyls
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Genus Species Location Stratigraphic position Material Images
Pachynolophus P. bretovense[13]
Primates
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Genus Species Location Stratigraphic position Material Images
Cryptadapis C. tertius[12] An adapiform primate.
Proeutheria
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Genus Species Location Stratigraphic position Material Notes Images
Pseudorhyncocyon P. cayluxi[12]
Rodents
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Genus Species Location Stratigraphic position Material Notes Images
Archaeomys A. intermedius[13]
A. quercyi[13]
Bernardia B. marandati[13]
Blainvillimys B. gemellus[13]
B. gousnatensis[13]
B. langei[13][34]
B. rotundidens[35]
Elfomys E. medius[13]
Eomys E. gigas[13]
E. minus[13]
E. quercyi[13]
Eucricetodon E. atavus[34]
E. quercyi[13]
Gliravus G. garouillensis[13]
G. itardiensis[13]
Issiodoromys I. limognensis[13]
I. pauffiensis[13][34]
Palaeosciurus P. goti[13][34]
Paradelomys Paradelomys spelaeus[13]
Patriotheridcmys P. altus[13]
P. altus neboulensis[13]
P. sudrei[13]
Pseudoltinomys P. gaillardi[34]
P. major[13]
P. phosphoricus[13]
Sciuromys S. cayluxi[36]
S. rigali[13]
Tarnomys T. quercynus[13]
Theridomys T. ludensis[13]

Birds

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Genus Species Location Stratigraphic position Material Images
Ameghinornis A. sp.[12]
Horusornis H. vianeyliaudae[12]
Idiornis I. itardiensis[12]
Itardiornis I. hessae[12]
Leptoganga L. sp.[12]
Necrobyas N. minimus[12]
Nocturnavis N. sp.[12]
Palaeoglaux P. perrierensis[12]
Palaeotodus P. escampsiensis[12]
P. itardiensis[12]
Paleseyvus P. escampensis[12]
Primocolius P. sigei[12]
P. minor[12]
Quercymegapodius Q. brodkorbi[12]
Quercypsitta Q. ivani[12]
Q. sudrei[12]
Recurvirostra R. sanctaeneboulae[12]
Sylphornis S. bretouensis[12]
Ventivorus V. ragei[12]
Caprimulgiformes
Genus Species Location Stratigraphic position Material Images
Euronyctibius E. kurochkini[37]
Quercypodargus Q. olsoni[37]

Reptiles

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Crocodiles
Genus Species Location Stratigraphic position Material Notes Images
Alligator A. gaudryi[38]
Lizards
Genus Species Location Stratigraphic position Material Notes Images
Ayalasaurus A. tenuis[39]
Brevisaurus B. smithi[39]
Cadurciguana C. hoffstetteri[12]
Cadurcogekko C. piveteaui[39]
Dracaenosaurus D. croizeti[39]
Eurheloderma E. gallicum[39]
Geiseltaliellus G. lamandini[39]
Mediolacerta M. roceki[39]
Necrosaurus N. cayluxi[39]
N. eucarinatus[39]
Omoiotyphlops O. priscus[39]
Paraplacosauriops P. quercyi[39]
Placosaurus P. rugosus[39]
P. sp.[39]
Plesiolacerta P. lydekkeri[39]
Pseudeumeces P. cadurcensis[39]
Pseudolacerta P. mucronata[39]
P. quercyini[39]
Quercycerta Q. maxima[39]
Quercygama Q. galliae[39]
Uromastyx U. europaeus[39]
Snakes
Turtles

Amphibians

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Frogs
Salamanders

Insects

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Flora

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References

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  1. ^ a b Quercy Phosphorites Formation at Fossilworks.org
  2. ^ a b Phosphorites du Quercy Formation at Fossilworks.org
  3. ^ a b Laloy et al., 2013
  4. ^ Legendre et al., 1997, p.331
  5. ^ a b Legendre et al., 1997, p.332
  6. ^ Astruc & Pellissié, 1988, p.8
  7. ^ Legendre et al., 1997, p.333
  8. ^ Tissier et al., 2017, p.6
  9. ^ a b Van de Kamp et al., 2018, p.2
  10. ^ Vasilyan, 2018, p.19
  11. ^ Van de Kamp et al., 2018, p.12
  12. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb bc bd be bf Legendre et al., 1997, p.334
  13. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak Legendre et al., 1997, p.335
  14. ^ Sudre, 1984
  15. ^ a b Mennecart & Métais, 2015
  16. ^ a b Blondel, 2005
  17. ^ Bonis et al., 2019, p.603
  18. ^ Bonis et al., 2019, p.612
  19. ^ a b c Peigné, 2003
  20. ^ a b Bonis et al., 2019, p.616
  21. ^ a b Peigné & Brunet, 2001
  22. ^ a b c Bonis et al., 2019, p.618
  23. ^ Peigné, 2000
  24. ^ Peigné, 2001
  25. ^ a b Bonis et al., 2019, p.614
  26. ^ a b Bonis et al., 2019, p.610
  27. ^ Bonis et al., 2019, p.604
  28. ^ Bonis et al., 2019, p.608
  29. ^ Bonis et al., 2019, p.615
  30. ^ Bonis et al., 2019, p.611
  31. ^ Hooker, 2018, p.236
  32. ^ Lavrov, 2007
  33. ^ Hugueney & Maridet, 2017
  34. ^ a b c d e Ginot et al., 2016, p.7
  35. ^ Hartenberger & Vianey-Liaud, 1978
  36. ^ Vianey-Liaud & Schmid, 2009
  37. ^ a b Mourer-Chauviré, 1989
  38. ^ a b c d e f g h i j k l Rage, 2006
  39. ^ a b c d e f g h i j k l m n o p q r s t Augé, 2005
  40. ^ Rage, 1988
  41. ^ a b Broin, 1977
  42. ^ Tissier et al., 2016
  43. ^ a b c Van de Kamp et al., 2018, p.4
  44. ^ a b c d e f g h Schmied et al., 2013, p.145
  45. ^ De Franceschi et al., 2006, p.99
  46. ^ a b De Franceschi et al., 2006, p.100
  47. ^ a b c d e De Franceschi et al., 2006, p.101

Bibliography

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Map reports
  • Astruc, J.G.; Pellissié, T. (1988), Notice explicative de la feuille Cahors 1:50,000 (PDF), BRGM, pp. 1–39, retrieved 2020-09-13
Paleontology

Further reading

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Media related to Quercy Phosphorites Formation at Wikimedia Commons