Perleidiformes

Perleidiformes
Fossil of besanensis Aetheodontus .
Temporal occurrence
Triassic to Lower Jurassic
249.7 to 175.6 million years
Locations
Madagascar , Europe , Russia , Greenland , Svalbard , North America , Australia .
Systematics
Over trunk : Neumünder (Deuterostomia) Trunk : Chordates (chordata) Sub-stem : Vertebrates (vertebrata) Superclass : Jaw mouths (Gnathostomata) Class : Ray fins (Actinopterygii) Order : Perleidiformes
Scientific name
Perleidiformes
Berg , 1937

The Perleidiformes are a group of extinct bony fish from the subclass of the cartilaginous organoids (Chondrostei) that lived from the Triassic to the Lower Jurassic .

features

They increasingly developed a body structure that corresponds to the more advanced ray fins (Actinopterygii). In contrast to more primitive cartilage organoids, the caudal fin is supported almost exclusively by fin rays. The muscle-supported caudal fin lobe is greatly reduced. The morphology of the jawbones also shows similarities with the new fins (Neopterygii) and other, more developed taxa of the ray fins. The Perleidiformes were rather small fish and were 4 to 23 centimeters long.

Familys

• Cephaloxenidae
• Colobodontidae
• Platysiagidae
• Peltopleuridae
• Cleithrolepidae
• Perleididae
• Platysiagidae

literature

• Robert L. Carroll : Paleontology and Evolution of the Vertebrates. Thieme, Stuttgart et al. 1993, ISBN 3-13-774401-6 .
• Karl Albert Frickhinger: Fossil Atlas of Fishes. Mergus, Verlag für Natur- und Heimtierkunde Baensch, Melle 1999, ISBN 3-88244-018-X .
• Joseph S. Nelson : Fishes of the World. 4th edition. John Wiley & Sons, Hoboken NJ 2006, ISBN 0-471-25031-7 .

Web links

Commons : Perleidiformes  - collection of images, videos and audio files

• Tree of Life Web Project. 2006. Perleidiformes . in The Tree of Life Web Project
• University of Bristol Perleidiformes