Where: Calvados, France (49.1° N, 0.4° W: paleocoordinates 36.6° N, 8.9° E)

• coordinate estimated from map

• outcrop-level geographic resolution

When: jamesoni-spinatum ammonoid zone, Calcaire à Bélemnites Formation, Late/Upper Pliensbachian (189.6 - 183.0 Ma)

• “Calcaire à Bélemnites” Formation, uppermost Pliensbachian (Lower Jurassic), Normandy (Dugué et al. 1998).

•The specimen MAE 2007.1.1(J) comes from the “Calcaire à Bélemnites” Formation (jamesoni to spinatum Zone, Pliensbachian) outcropping in the Roche-Blain quarries, located in the commune of Fresney-le-Puceux near the city of Laize-la-Ville, approximately 10 km south of Caen (Fig. 1). The absence of associated diagnostic ammonite markers prevents direct age assignment of the specimen to the ammonite Zone level.

•The nannofossil assemblages from the rock matrix adhering to the specimen were examined in order to determine the age of the specimen. The assemblage is dominated (76.9% of specimens) by murolith-coccoliths (composed of a wall-like, sub-vertical rim; Fig. 2A-F), while placoliths (formed by two sub-horizontal shields; Fig. 2G-I) and the nannolith Schizosphaerella are rare. Crepidolithus impontus (C. cavus in Bown 1987), Bussonius prinsii, and Calyculus sp. were recorded in the assemblage (Fig. 2 A-C and I). In different sections from central and northern Italy these three taxa are recorded stratigraphically one after the other in sediments attributed to the spinatum ammonite Zone, uppermost Pliensbachian (Mattioli and Erba 1999). The same record is reported by Veiga de Oliveira et al. (2005) in Portugal, and by Perilli et al. (2004) in northern Spain. Conversely, rare and sporadic occurrences of both Calyculus spp. and B. prinsii have been reported as low as the lower Pliensbachian of NW Europe, but these taxa become consistently present in the uppermost Pliensbachian (Bown and Cooper 1998). These authors also report C. impontus from the spinatum ammonite zone. The first occurrence of C. impontus is used to define the base of the NJ5b nannofossil subzone (Bown and Cooper 1998) that spans the uppermost Pliensbachian and the lowermost Toarcian. The lack of other, typical lowermost Toarcian species in the sample from the matrix of MAE 2007.1.1(J) leads us to correlate the sample with the uppermost Pliensbachian (Bown and Cooper 1998; Mattioli and Erba 1999; Perilli et al. 2004; Veiga de Oliveira et al. 2005; Mailliot et al. 2006). Very few small Lotharingius specimens, which are usually recorded stratigraphically below C. impontus (Bown 1987; Bown and Cooper 1998; Mattioli and Erba 1999), are present in the studied sample (i.e., L. frodoi in Fig. 2H). The dominance of muroliths in the studied sample is another argument to support a late Pliensbachian age. In fact, Mailliot et al. (2007) show that placoliths became dominant over muroliths in the basal Toarcian.

Environment/lithology: marine; lithology not reported

Size class: macrofossils

Collected in the 1980s

Collection methods: quarrying,

• MAE collection, Musée de l'Agglomération d'Elbeuff, Elbeuf-sur-Seine, France

Primary reference: P. Vincent, N. Bardet, and E. Mattioli. 2013. A new pliosaurid from the Pliensbachian (Early Jurassic) of Normandy (Northern France). Acta Palaeontologica Polonica [R. Benson/R. Benson/R. Benson]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 131488: authorized by Roger Benson, entered by Roger Benson on 25.07.2012

Creative Commons license: CC BY (attribution)