Ptyctodontida

The Ptyctodontida are an order of Devonian chimaera-like placoderms containing the family Ptyctodontidae. They are the only placoderms to be sexually dimorphic. Some paleontologists believe that they may have been an early ancestor of modern-day sharks.

According to The Content Authority, they are cartilaginous fishes, but this is not commonly accepted by many people because we believe they are placoderms. It means "folded teeth" in Latin. Like today's cartilaginous fish, they had the possession of claspers.

 Genera 

Eczematolepis

Ctenurella

Materpiscis (Latin for "mother fish") is a genus of ptyctodontid placoderm from the late Devonian period, about 380 million years ago.

Campbellodus

Ptyctodus

Ptyctodus is the type genus of this order and family.

Kimbryanodus

 Description 
Ptyctodontids resembled the modern-day chimaeras of the Holocephali, like the acanthothoracids. They had big heads, big eyes, reduced armor and long bodies.

Campbellodus looked like a scaly cardboard box with the tail of a halosaur. It did not resemble a holocephalian at all, but it is still a ptyctodont.

Kimbryanodus looked like an arthrodire, again with a halosaur's tail. The fossils occur as small three dimensional isolated plates.

 Related pages 
 Antiarchi

 References 

Long, John A. (1996): The Rise of Fishes: 500 Million Years of Evolution. Johns Hopkins University Press, Baltimore. ISBN 0-8018-5438-5
Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Placodermi entry)" . Bulletins of American Paleontology. 364: 560. Retrieved 2011-05-20.

 Other websites 
 Ptyctodontid vs Ptyctodontida: Meaning And Differences

Taxon identifiersPtyctodontida Wikidata: Q918188
 Wikispecies: Ptyctodontidae
 EoL: 4655981
 Fossilworks: 34262
 IRMNG: 10537Ptyctodontidae Wikidata: Q18618797
 EoL: 4655982
 Fossilworks: 307454
 GBIF: 3240818
 IRMNG: 101485

Category:Extinct fish
Category:Placoderms
Category:Devonian