Swedish paleontologist F . Brotzen described placodont armor from Makhtesh Ramon in 1957, naming the species " Psephosaurus mosis " and " Psephosaurus picardi " from the " Beneckeia " and " Ceratites " beds, respectively . " P . picardi " is now considered a " nomen dubium " because it was based on an impression of the inner surface of the carapace that did not possess any distinct features.
