Platysomiformes

Platysomiformes
Platysomus gibbosus from the Middle Permian of Russia.
Temporal occurrence
Mississippium (Lower Carboniferous) to Lower Triassic
Locations
North America , South America , Europe , Svalbard , Madagascar , South Africa , Australia
Systematics
Over trunk : Neumünder (Deuterostomia) Trunk : Chordates (chordata) Sub-stem : Vertebrates (vertebrata) Superclass : Jaw mouths (Gnathostomata) Class : Ray fins (Actinopterygii) Order : Platysomiformes
Scientific name
Platysomiformes
Hay , 1902

The platysomiformes are an extinct group of bony fish . They lived from the Mississippium to the Lower Triassic in fresh water and in the sea.

features

The Platysomiformes resembled the recent St. Peter's fish-like (Zeiformes) and had a high-backed, laterally flattened body with an oval or rhombic outline. They were the first group of fish to deviate from the spindle-shaped form of primitive Actinopterygii. This deep-bellied shape is found in recent species, especially in fish that live in calm water. The dorsal and anal fins could be drawn out like a seam. The scales of the Platysomiformes consisted only of bone tissue, ganoin and cosmin layers were missing. The species of the genus Chirodus had a bite.

Families and genera

• Bobasatraniidae
  • Bobasatrania
• Platysomidae
  • Chirodus
  • Paranaichthys
  • Platysomus

literature

• Robert L. Carroll : Paleontology and Evolution of the Vertebrates. Thieme, Stuttgart et al. 1993, ISBN 3-13-774401-6 .
• Textbook of special zoology. Volume 2: Dietrich Starck (Ed.): Vertebrates. Part 2: Kurt Fiedler: Fish. Fischer, Jena 1991, ISBN 3-334-00338-8 .
• Joseph S. Nelson , Terry C. Grande, Mark VH Wilson: Fishes of the World. Wiley, Hoboken, New Jersey, 2016, ISBN 978-1118342336 .