Alcide d'Orbigny
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Alcide Charles Victor Marie Dessalines d'Orbigny was a French naturalist who made major contributions in many areas, including zoology, palaeontology, geology, archaeology and anthropology.
Illustration of Potamotrygon orbignyi by Castelnau.
Callovian
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In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 165.3 ± 1.1 Ma and 161.5 ± 1.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian.
Matmor Formation (Callovian, Peltoceras athleta Zone) in Makhtesh Gadol, Israel.
Callovian rocks of the Osgodby Formation at Cayton Bay in North Yorkshire, England