(Submitter’s note: David Peters is an extremely prolific palaeomtology crank who started with fallaciously reconstructing pterosaurs according to artifacts based on photos alone and then declaring new family trees of reptiles based on these wrong misconstructions and a small set of characteristics. He then expanded to all of chordates - without adding new characteristics to his program. Of course, his theories are accepted only because of the narrow-minded fools in academia calling him mad.
Here is one of the more accessible pieces of his crackpottery.)

Rhincodon typus (Smith 1829; up to 18.8m) is the extant whale shark, one of the most primitive sharks, retaining similarities to Thelodus (Submitter’s note: a small jawless fish of the Silurian). Terminal jaws are essentially transverse. They contain 300-350 rows of tiny teeth and 20 filter pads, reminiscent of Thelodus and shark skin. This is the origin of teeth in vertebrates. The orbits occupied the front corners of the poorly ossified skull. Nares were inside the mouth. Open spiracles were posterior to the orbits. Although an open seas swimmer, the flattened shape of Rhincodon is a legacy from its bottom-dwelling ancestry.

Manta birostris (formerly Cephalopterus manta, Bancroft 1829; up to 5.5m in length) is the extant manta ray. Traditinally a derived member of the guitarfish, skates and rays clade, Manta nests here with Rhincodon, including an anteriorly facing mouth, nares inside the mouth, tiny blankets of teeth and a diet of planktonic prey. The cephalic fins are like the lobes of cownose rays, but detached anteriorly. So, what to make of this ray with a whale shark mouth, nose, eyes and teeth?