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),Quercy Phosphorites Formation at Fossilworks.orgPhosphorites du Quercy Formation at Fossilworks.org 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.

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 The first phosphate deposits in Quercy were discovered in 1869 and published by Daubré and Trutat independently in 1871.Legendre et al., 1997, p.331 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.Legendre et al., 1997, p.332

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.Astruc & Pellissié, 1988, p.8 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. These ages correspond to the latest Bartonian to Chattian, from about 38 to 25 Ma.Legendre et al., 1997, p.333

Paleontological significance

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,Tissier et al., 2017, p.6 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. 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.Vasilyan, 2018, p.19 It is assumed that the Quercy arthropods fossilized by a rapid fixation by phosphate-rich water followed by encrustation and mineralization.Van de Kamp et al., 2018, p.12

Paleofauna The following fossils have been reported from the formation:Legendre et al., 1997, p.334Legendre et al., 1997, p.335

Mammals

Apatemyidae Genus Species Location Time Material Note ImagesChardinyusC. sp. An apatotheria.Heterohyus H. (Chardinyus) nanus An apatemyid. H. (Gervaisyus) pygmaeus Gervaisyus G. sp.

Artiodactyls Genus Species Location Time Material Notes ImagesBachitherium B. guirounetensis B. lavocati Cryptomeryx C. gaudryiSudre, 1984 Dichobune D. sigei Dichodon D. vidalenci Iberomeryx I. matsoui Mosaicomeryx M. quercyiMennecart & Métais, 2015 ParoxacronP. bergeriBlondel, 2005 Plesiomeryx P. cadurcensis Prodremotherium P. elongatum Pseudamphimeryx P. salesmeiRobiacina R. lavergnensisR. quercyi Tapirulus T. perrierensis

Carnivora Genus Species Location Time Material Notes Images Amphicynodon A. typicusBonis et al., 2019, p.603 Pech Crabet locality Oligocene Two hemi-mandibles An early amphicynodontidae caniform Cephalogale C. sp.Bonis et al., 2019, p.612 A piece of hemi-mandibleCynodyctisC. lacustris neboulensis Sainte Néboule A mandible An amphicynodontidae caniform. Dinailurictis D. bonaliPeigné, 2003Bonis et al., 2019, p.616 La Tuque Oligocene. Several holotypes consist of a fragment of the left upper canine, lower canine, distal right humerus, distal left ulna, and a proximal piece of the right femur. A nimravid felidae Eofelis E. edwardsiiPeigné & Brunet, 2001 A nimravid E. giganteusPeigné, 2000 Phosphorites du Quercy A mandible cf. E. sp.Peigné, 2001 Eusmilus E. bidentatusBonis et al., 2019, p.618 Eocene/Oligocene A edentulous hemi-mandible and a fragment of upper canine A nimravidHuntictisH. minima Gardiol 3 locality Early Oligocene A holotype consists of a dentition. A small musteloidMustelictis M. cf. majorBonis et al., 2019, p.614 A part of right hemi-mandible with alveolus of p1, p2, fragments of p3 roots, and p4-m1. M. aff. olivieri A holotype specimen consists of a skull and a hemi-mandible. Nimravus N. intermedius MP 22 localities, La Plante2, Mas de Got and Valbro localities Oligocene A left hemi-mandible with m1 A nimravid felidae. Pachycynodon P. amphictinaBonis et al., 2019, p.610 Oligocene Multiple specimens consist of hemi-mandible and dentitions. P. crassirostrisBonis et al., 2019, p.604 P. cf. dubius P. cf. filholiBonis et al., 2019, p.608 Palaeogale P. sectoria Valbro locality Oligocene A specimen consists of p4 dentition. An early feliformia Peignictis P. pseudamphictisBonis et al., 2019, p.615 Valbro locality Early Oligocene A posterior part of hemi-mandible A carnivoran with uncertain affinitiesQuercylurus Q. major Phosphorites du Quercy Oligocene A maxilla A nimravidStorchictisS. miacinus Phosphorites du Quercy Late Eocene A mandible An Amphicyonidae Wangictis W. tedfordiBonis et al., 2019, p.611 Phosphorites du Quercy Early Oligocene A left hemi-mandible with c-m2 An Amphicynodontidae

Chiroptera Genus Species Location Time Material Notes ImagesHipposideros H. pseudorhinolophus sehlosseri An early roundleaf bat. H. pseudorhinolophus trassounius H. pseudorhinolophus zbrjdi Leuconoe L. lavocati An early vespertilionid bat. Palaeophyllophora P. oltina An early hipposiderid bat. P. quercyiStehlinia S. bonisi An early natalidae bat S. minor Vaylatsia V. garouillasensis VespertiliavusV. gerscheli An early Emballonurid bat V. gracilis V. lapradensis

Creodonta Genus Species Location Time Material Images Paracynohyaenodon P. magnus Parapterodon P. lostangensis

Euarchonta Genus Species Location Time Material Images Darbonetus D. aubrelongensisHooker, 2018, p.236

Hyaenodonta Genus Species Location Time Material Notes Images Paroxyaena P. pavloviLavrov, 2007 Phosphorites du Quercy Late Eocene A partial skull A hyaenodont

Lipotyphla Genus Species Location Time Material Notes Images Amphidozotherium A. cayluxi Darbonetus D. aubrelongensis D. tuberi Myxomygale M. antiquaHugueney & Maridet, 2017 Saturninia S. beata S. pelissiei

Marsupials

Genus Species Location Time Material Notes ImagesAmphiperatherium A. bourdellense Le Bretou Locality Oligocene A. lamandiniA. minutumPeratherium P. bretouense P. cayluxi P. lavergnense P. perrierense

Perissodactyls Genus Species Location Time Material Images Pachynolophus P. bretovense

Primates Genus Species Location Time Material Images Cryptadapis C. tertius An adapiform primate.

Proeutheria Genus Species Location Time Material Notes Images Pseudorhyncocyon P. cayluxi

Rodents Genus Species Location Time Material Notes Images Archaeomys A. intermedius Pech du Fraysse Oligocene A theridomyidae rodent A. quercyi Oligocene Bernardia B. marandatiBlainvillimysB. gemellus B. gousnatensis B. langeiGinot et al., 2016, p.7 B. rotundidensHartenberger & Vianey-Liaud, 1978 Elfomys E. mediusEomysE. gigas Pech du Fraysse Locality Late Oligocene A specimen An eomyidae rodent E. minus Pech du Fraysse Locality A specimen E. quercyi Pech du Fraysse Locality A specimen Eucricetodon E. atavus E. quercyiGliravus G. garouillensis G. itardiensisIssiodoromys I. limognensis I. pauffiensis Palaeosciurus P. goti Paradelomys Paradelomys spelaeus Patriotheridcmys P. altus P. altus neboulensis P. sudreiPseudoltinomys P. gaillardi P. major P. phosphoricusSciuromys S. cayluxiVianey-Liaud & Schmid, 2009 S. rigali Tarnomys T. quercynus Theridomys T. ludensis

Birds Genus Species Location Time Material Note ImagesAmeghinornisA. minor Phosphorites du Quercy Late Eocene A specimen An early european seriema Euronyctibius E. kurochkiniMourer-Chauviré, 1989 Phosphorites du Quercy Eocene A right humerus An early nightjarHorusornisH. vianeyliaudae La Bouffie Locality Eocene A specimen An early accipitriformesDynamopterusD. velox Near Caylus Oligocene Almost complete right humerus An extinct cuckoo bird, synonymous with Dynamopterus velox Itardiornis I. hessae Eocene/Oligocene A specimen A Messelornithidae bird Leptoganga L. sp. Necrobyas N. minimus Nocturnavis N. sp. Palaeoglaux P. perrierensis An early owlPalaeotodus P. escampsiensis Late Eocene A specimen An early todies P. itardiensis Early Oligocene A specimen Paleseyvus P. escampensisPrimocolius P. sigei Le Bretou locality Eocene A limb element consists of a practically complete left humerus P. minor A near-complete right tarsometatarsal Quercymegapodius Q. brodkorbi A Quercymegapodiidae bird Quercypodargus Q. olsoniQuercypsitta Q. ivani La Bouffie locality Late Eocene A holotype specimen consists of three coracoids An early offshoots of parrot Q. sudrei Fragmentary sets of postcrania, which consist of foot and wing bones Recurvirostra R. sanctaeneboulaeStrigogypsS. dubius Phosphorites du Quercy Late Eocene A specimen Sylphornis S. bretouensis Ventivorus V. ragei Le Bertou Locality An early nightjar

Reptiles Crocodilians Genus Species Location Time Material Notes Images Arambourgia A. gaudryi

Lizards Genus Species Location Time Material Notes Images Ayalasaurus A. tenuisAugé, 2005BauersaurusB. cosensisČerňanský, A.; Daza, J. D.; Tabuce, R.; Saxton, E.; Vidalenc, D. (2023). "An early Eocene pan-gekkotan from France could represent an extra squamate group that survived the K/Pg extinction". Acta Palaeontologica Polonica. 68 (4): 695–708. doi:10.4202/app.01083.2023. Cos Locality Uppermost Early Eocene The upper maxilla) and lower jaw fragments. A pan-gekkotan lizard. Brevisaurus B. smithiCadurciguanaC. hoffstetteri Cadurcogekko C. piveteauiCadurcopanoplosC. vaylatsensisLemierre, Alfred; Georgalis, Georgios L. (2025). "Diversity in a greenhouse world: Herpetofauna from the late Eocene (MP 17A) of la Bouffie, Quercy Phosphorites (Lot, SW France)". Swiss Journal of Palaeontology. 144 40. doi:10.1186/s13358-025-00370-9. La Bouffie locality Late Eocene Two holotypes consist of a single incomplete frontal bone and a partial right mandible. A Glyptosaurinae anguid. Dracaenosaurus D. croizeti Eurheloderma E. gallicum Geiseltaliellus G. lamandiniAn early iguanian lizardLavergnesaurusL. lamarcki Lavergne Bartonian A left dentary An early skink Mediolacerta M. rocekiNecrosaurusN. cayluxi N. eucarinatus Omoiotyphlops O. priscus Paraplacosauriops P. quercyiPhosphoriguanaP. peritechne La Bouffie Locality Late Eocene A single partial lower jaw A probable member of pleurodonta Placosaurus P. rugosus P. sp. Plesiolacerta P. lydekkeri Pseudeumeces P. cadurcensisPseudolacertaP. mucronata P. quercyini Quercycerta Q. maximaQuercygamaQ. galliaeMiddle Eocene A cranial material consists of a skullAn early relatives of wall lizardsTimon T. planeutes Uromastyx U. europaeus An early spiny-tailed lizard

Snakes