Belmont d’Azergues (Lafarge quarry), Lower Aalenian (opalinum Zone) (Jurassic of France)

Where: Rhone, France (45.9° N, 4.7° E: paleocoordinates 35.0° N, 15.3° E)

• coordinate estimated from map

• small collection-level geographic resolution

When: Leioceras opalinum ammonoid zone, Early/Lower Aalenian (175.6 - 171.6 Ma)

• The early Aalenian sequence (bifrons zone to variabilis zone)

Environment/lithology: marine; shelly/skeletal, yellow, sandy limestone and red, yellow, calcareous sandstone

• a succession of fully marine strata... that were deposited at relatively shallow depths near the easternmost reach of the Massif Central
• An intensively bioturbated, massive and sandy yellowish bioclastic limestone bed at 12.4 m (‘Dalle à Leioceras’; Elmi & Rulleau, 1991) marks the base of the more calcareous and coarser sequence of the lower Aalenian (opalinum ammonite zone), which consists mainly of yellowish to pinkish sandy calcarenite and calcareous sandstone beds

Size class: macrofossils

Collected in 1983-2013

Collection methods: quarrying,

• Following 30 years of collection (in 2013), including excavations undertaken

•in 2009 and 2010 in the southern part of the quarry allowed new detailed observations and sampling of the Toarcian to lowermost Aalenian sequence, including the lower Toarcian interval, which is otherwise poorly represented in the quarry (Rulleau, 1997).

•Musee des Amis de la Mine in Saint-Pierre La Palud, Rhone department, France (MAMSPLP).

•Espace Pierres Folles in Saint-Jean-des-Vignes, Beaujolais, France (PF)

Primary reference: P. Vincent, J. E. Martin, V. Fischer, G. Suan, B. Khalloufi, B. Suchéras-Marx, A. Léna, K. Janneau, B. Rouselle and L. Rulleau. 2013. Marine vertebrate remains from the Toarcian–Aalenian succession of southern Beaujolais, Rhône, France. Geological Magazine [R. Benson/R. Benson]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 140481: authorized by Roger Benson, entered by Roger Benson on 11.03.2013, edited by Matthew Clapham

Creative Commons license: CC BY (attribution)

Taxonomic list

Cephalopoda
 Nautilida - Cenoceratidae
Cenoceras aff. smithi Foord and Crick 1890 nautiloid
Cenoceras majesticum n. sp. Rulleau 2008 nautiloid
Chondrichthyes
 Hybodontiformes -
Hybodontiformes indet. elasmobranch
PF Aal 32(?) or 321(?), spine
 Hybodontiformes - Acrodontidae
Asteracanthus sp. Agassiz 1837 elasmobranch
PF Aal 312, tooth
Reptilia
 Sauropterygia -
Plesiosauria indet. de Blainville 1835 plesiosaur
PF Aal 186–187, postcranial remains preserved in two incompletely prepared blocks of fine-grained, winecoloured sandstone: dorsal vertebrae, ribs and girdle fragments
 Ichthyosauria -
Ichthyosauria indet. ichthyosaur
PF Aal 309 (coracoid), PF Aal 308 (partial rostrum)