Evolution of tetrapods for a magazine article. By Maija Karala:

"The animals depicted are, from bottom to top, Eusthenopteron, Panderichthys, Tiktaalik, Acanthostega, Ichthyostega and Pederpes. I tried to depict them as independent lineages instead of the often misunderstood linear progression. I also pointed it out in the text itself for a couple of times.

I only included the best-known fossils and left all the isolated jaw bones and head parts out, because I didn’t want to speculate too much.”

The Panderichthys (1941)

Phylum : Chordata
Class : Sarcopterygii
Order : Elpistostegalia
Family : Panderichthyidae
Genus : Panderichthys
Species : P. rhombolepis

  • Middle Devonian (380 Ma)
  • 1,3 m long
  • Northern hemisphere

The slow, gradual progression from prehistoric fish to the earliest tetrapods encompassed numerous intermediate stages, many of them transpiring in the Devonian period. Mostly still a fish, by the modern definition of the word, the 380-million-year-old Panderichthys seems to have just embarked on those anatomical changes that would enable its descendants to crawl up onto dry land 5 or 10 million years later. Notably, the front fins of Panderichthys offered primitive hints of the types of bones found in the limbs of later tetrapods, though its rear fins were less revolutionary. Long story short, it’s possible that Pandericthys was able to climb up out of shallow tidal basins and support itself, clumsily, on its front fins for quick gasps of oxygen-rich air.