The Canjuers Lagerstätte is a Konservat-Lagerstätte located inside the military camp of Canjuers, in Haute Provence, in the Var department in South-East France.

Geology and stratigraphy

From a stratigraphic point of view, this fossil deposit is located inside the 'Calcaire Blancs de Provence' Formation, a 200-meter-thick limestone assemblage. The lithographic limestone of Canjuers, which bears almost all significant fossils from the Lagerstätte, is a thin layer (around 6 meters) at the basis of the Biomicrites de Sainte-Croix member, the later member of the Calcaires Blancs de Provence Fm. This layer has been dated by ammonite analysis to the Lower Tithonian (Neochetoceras mucronatum biozone), around .

The Canjuers site facies outcrop in the Petit Plan de Canjuers plateau, and a quarry was exploited in the locality "Les Bessons". They correspond to deposits inside a sub-circular depression whose area is estimated to be only 1 km2. Their total thickness is around 12 m. They are divided in three lithologic units, from bottom to top : The lithographic limestone per se, made of thin limestone, finely laminated, around 6 m thick. Those bears almost every remarkable fossils from the site (Lagerstätte). Bioclastic limestone 4.5 m thick. Those are packstone or grainstone limestone, with chert nodule levels. Their bioclasts are made of corals, sea urchins, bivalves, brachiopods and sponges fragments, with burrows and some plant remains. The banks show quasi-planar oblique surface. The sub-lithographic limestone with chert nodule levels, 1.5 m wide, in thick banks perforated by burrows attributed to the ichnotaxon Tubularina lithographica.

Paleoenvironment

The lithographic limestone deposit environment was protected from the Tethys Ocean open sea by a continuous reef barrier. The lithographic limestone was deposited in a large lagoon whose various parts were successively above and below water, and where several small coral islands emerged. Meteoric water supplies are likely.

Paleontology

Actinopterygians

Genus Species Order Family Images Caturus C. sp. Amiiformes Caturidae Eugnathus E. sp. Amiiformes Caturidae Gyrodus G. sp. Pycnodontiformes Gyrodontidae Proscinetes P. sp. Pycnodontiformes Pycnodontidae Pachycormidae Pachycormiformes Pachycormidae Pholidophorus P. sp. Pholidophoriformes Pholidophoridae Leptolepis L. sp. Leptolepiformes Leptolepidae Tharsis T. sp. Leptolepiformes Leptolepidae Ophiopsis O. sp. Ionoscopiformes Ophiopsidae Elopidae Elopiformes Elopidae Lepidotes L. sp. Lepisosteiformes Lepidotidae Belonostomus B. sp. Aspidorhynchiformes Aspidorhynchidae Naiathelon N. okkidion Elopomorpha

Sarcopterygians

Genus Species Order Family Images Undina U. sp. Actinistia Coccoderma C. sp. Actinistia

Chondrichthyans

Genus Species Order Family Images Palaeocarcharias P. stromeri Lamniformes Known from an articulated almost-complete specimen.

Reptiles

Genus Species Order Family Images Caesaria C. templaria Thalassochelydia Eurysternum E. sp. Thalassochelydia Eurysternidae Solnhofia S. sp. Thalassochelydia Homoeosaurus H. maximiliani Rhynchocephalia Sphenodontidae Leptosaurus L. pulchellus Rhynchocephalia Sphenodontidae Piocormus P. laticeps Rhynchocephalia Sphenodontidae Pleurosaurus P. ginsburgi Rhynchocephalia Pleurosauridae P. goldfussi Rhynchocephalia Pleurosauridae Aeolodon A. priscus Mesoeucrocodylia Teleosauridae Compsognathus C. longipes Dinosauria Compsognathidae Cycnorhamphus C. suevicus Pterosauria Gallodactylidae

Echinoderms Genus Species Order Family Images Plegiocidaris P. marginata Echinoidea Cidaroida Rhabdocidaris R. nobilis Echinoidea Cidaroida Diplocidaris D. gigantea Echinoidea Cidaroida Hemicidaris H. crenularis Echinoidea Hemicidaroida Acrocidaris A. nobilis Echinoidea Hemicidaroida Hessotiara H. florescens Echinoidea Hemicidaroida Pseudosalenia P. aspera Echinoidea Salenioida Pleurodiadema P. stutzi Echinoidea Phymosomatoida Acropeltis A. aequituberculata Echinoidea Arbacioida Magnosia M. nodulosa Echinoidea Arbacioida Pentasteria P. sp. Asteroidea Paxillosida Geocoma G. canjuersensis Ophiuroidea Ophiuridae G. aff. carinata Ophiuroidea Ophiuridae Amphiuridae Ophiuroidea Amphiuridae Ophiurella O. aff. speciosa Ophiuroidea incertae sedis Comaturella C. pinnata Crinoidea Comatulida Saccocoma S. tenella Crinoidea Roveacrinida

Brachiopods Genus Species Order Family Images Torquirhynchia T. guebhardi Rhynchonellida Septaliphoria S. obtusa Rhynchonellida Somalirhynchia ? S. sp. Rhynchonellida Juralina J. insignis Terebratulida Moeschia M. aff. foraminata Terebratulida Ismenia I. pectunculoides Terebratulida "Zeilleria" Z. aff. pentagonalis Terebratulida

Molluscs Genus Species Order Family Images Modiolus M. imbricatus Bivalvia Entolium E. corneolum Bivalvia Chlamys C. textoria Bivalvia Spondylopecten S. subpunctatus Bivalvia Nanogyra N. striata Bivalvia Actinostreon A. gregareum Bivalvia Dorsoplanitoides D. triplicatus Cephalopoda Usseliceras U. (Subplanitoides) altegyratum Cephalopoda U. (Subplanitoides) aff. spindelense Cephalopoda U. (Subplanitoides) cf. schwertschlageri Cephalopoda U. (Usseliceras) cf. franconicum Cephalopoda Hibolites H. sp. Cephalopoda

Crustaceans Genus Species Order Family Images Cycleryon C. bourseaui Decapoda Kouphichnium K. lithographicum Chelicerata Xiphosura

References