The Palaeocene of Belgium & France.
(Selandian & Thanetian)
 
 

 

In Belgium, the Selandian Orp Sands (Herman, 1972) and the late Thanetian Dormaal Sands (Smith, 1999) are exposed; unfortunately large exposures or quarries don't exist anymore, only temporary outcrops.

The Belgian Selandian consists of a poorly diversified fauna, dominated by squalidae and Striatolamia striata (Winkler, 1874). The Dormaal Sand Member to the contrary, famous for its rich mammal fauna (Quinet, 1966), possesses a highly diversified elasmobranch fauna, 46 taxa were recognized (Smith et al., 1999).


Most material figured on this part of the website is found on Thanetian localities. The Thanetian is well presented in France, is more diversified and dominated by Striatolamia striata (Winkler, 1874). Clear differences between the middle and late Thanetian can be noticed.
 

In the middle Thanetian (NP8), Palaeohypotodus rutoti (Winkler, 1874) and Glueckmanotodus heinzelini (Casier, 1967) are commonly found. Odontaspis winkleri Leriche, 1905 and Paraorthacodus eocaenus (Leriche, 1902) are found from time to time and Brachycarcharias lerichei (Casier, 1946) is reported for the first time. Batoids are not very diversified, represented by Hypolophodon, “Myliobatis” and very exceptionally Torpedo dormaalensis Smith, 1999.

In the late Thanetian is Palaeohypotodus becoming scarce, while Brachycarcharias lerichei (Casier, 1946) and Jaekelotodus robustus (Leriche, 1921) are found more regularly; O. winkleri Leriche, 1905 is getting larger. Isurolamna inflata (Leriche, 1905) and Isurolamna affinis (Casier, 1946) co-existed. Physogaleus secundus (Winkler, 1874) and Pachygaleus lefevrei (Daimeries, 1891) are appearing for the first time. Batoids are more varied; also Coupatezia and Burnhamia were collected. This horizon is very similar to the Dormaal Sands in Belgium. Both are belonging to the very late Palaeocene (NP9).

Otodus obliquus AGASSIZ 1843 appeared in the Thanet Sand Formation (Ward, 1980). In our region this species was found in both middle and late Thanetian sediments, mostly being very small. A couple of large (+40 mm) Otodus specimens were found in the middle Thanetian; some specimens already have serrations at the basal part of the crown. On different Thanetian localities, some small Cretalamna teeth were collected; survivors of the Mesozoic. Notidanodon loozi (Vincent, 1876) is only very occasionally found in the Thanetian, but in the Selandian Orp Sands, this species is more regularly reported.

 
 

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HERMAN, J., 1972. Les vertébres du Landénien Inférieur de Maret (Hameau d’Orp-le-Grand). Service Géologique de Belgique, Bruxelles.

SMITH, R., SMITH, T. & STEURBAUT, E., 1999. Les élasmobranches de la transition Paléocène-Eocène de Dormaal (Belgique): implications biostratigraphiques et paléobiogéographiques. Bull. Soc. Géol. France, t. 170, n° 3

SMITH, R., 1999. Elasmobranches nouveaux de la transition, Paléocène-Eocène de Dormaal (Belgique). KBIN Bulletin, Aardwetenschappen, 69.

WARD, D.J., 1980. The Distribution of Sharks, Rays and Chimaeroids in the English Palaeogene. Tertiary Research, 3(1): 13-19.

© P. De Schutter - 2011