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Calvin once imagined himself as an unnamed pterosaur while attending school. He was attacked by a plesiosaur (who, in actuality was Miss Wormwood) causing Calvin to snap back to reality. Miss Wormwood berated Calvin for not paying attention.

After attempting to make Calvin pay more attention, Miss Wormwood gave up, leaving Calvin to continue his fantasy.

The Identity may be Pterodactylus which has similar anatomy and lived at times when large pliosaurs like the one shown lived. However it may just represent a generic genus and not be any specific species.