Callovien

Matmor Formation (Jurassic, Callovian) exposed in Makhtesh Gadol, Israel. (Electricity pylon for scale).

Marnes du Callovien, localement nommées les « terres grises », sur le territoire de la commune de Quissac, dans le Gard (région Occitanie, France).

Coleia gigantea. Stage : Callovian between 164.7 ± 4.0 Ma (million years ago) and 161.2 ± 4.0 Ma (million years ago).

An atypical (without intertidal and supratidal environment) carbonate platform settles down along the margin. Shallow water oolithes and oncoids are deposited in a narrow zone between a basin with Cancellophycus to the north and a marine/swampy plain with abundants mollusc fauna. However the Mytilus formation, rich in bathonian and callovian foraminifera (Septfontaine, 1984 etc.), develop thick limestone beds tenth of meter above, wrongly attributed to the upper Jurassic. See discussion in Septfontaine (1984).

Partial skull and anterior cervical vertebrae of unidentified pliosaurid plesiosaurian (MPPL 18797) from the uppermost Callovian–middle Oxfordian of Kaberlaba (Asiago, Italy), in left lateral view. Photograph (A) and explanatory drawing (B). White, preserved bone surfaces; dark grey, preserved margins of skull fenestrae; light grey, eroded bone surface; cross hatching, broken bone.

Reconstructed skull of Wiehenvenator albati based on holotype specimen (white). Scale bar is 10cm, image if 10px/cm. Unknown material based on related Torvosaurus tanneri. Cranial anatomy based on Rauhut et al (2016) "A new megalosaurid theropod dinosaur from the late Middle Jurassic (Callovian) of north-western Germany: implications for theropod evolution and faunal turnover in the Jurassic"

Ophthalmosaurus icenius, from the time of the Callovian period of the Middle Jurassic. This specimen was found in Oxford Clay, in Peterborough, England. Photo lightly touched up to remove lighting flares.

Ophthalmosaurus icenius, from the time of the Callovian period of the Middle Jurassic. This specimen was found in Oxford Clay, in Peterborough, England. Photo lightly touched up to remove lighting flares.

Ophthalmosaurus icenius, from the time of the Callovian period of the Middle Jurassic. This specimen was found in Oxford Clay, in Peterborough, England. Photo lightly touched up to remove lighting flares.

Ophthalmosaurus icenius, from the time of the Callovian period of the Middle Jurassic. This specimen was found in Oxford Clay, in Peterborough, England. Photo lightly touched up to remove lighting flares.