Despite the ancient origins of the Polypteriformes, the earliest fossils that can be confidently assigned as being of the Polypterus lineage are from the Middle Eocene (Lutetian) of Libya.

[1] In addition, studies exclusively using phylogenetic inferences have found that Polypterus may have only diverged from Erpetoichthys during the Neogene.

[4] Around the time following its initial discovery, some entertained the idea of Polypterus as a living fossil representing the "missing link" between fishes and tetrapods, illustrating a transitional form at the midpoint between finned and limbed vertebrates.

[4] In 1861, Thomas Huxley created the order Crossopterygii to house animals, fossil and living, that possessed lungs and fleshy pectoral fins with lobes.

[4] Two men, Nathan Harrington and John Samuel Budgett, attempted to answer this question by making repeated expeditions to Africa.

[4][5] Drawing on this work, in 1907, E. S. Goodrich reported to the British Association the then current state of evidence 'against' Polypterus being a crossopterygian, placing it within the palaeoniscids, the most primitive actinopterygians.

[6] Much later, in 1946, Romer confirmed this view, but he also wrote, "The weight of Huxley's [1861] opinion is a heavy one, and even today many a text continues to cite Polypterus as a crossopterygian and it is so described in many a classroom, although students of fish evolution have realized the falsity of this position for many years.

"[7] Hall (2001), relying on Patterson (1982) and Noack et al. (1996), writes, "Phylogenetic analyses using both morphological and molecular data affirm Polypterus as a living stem actinopterygian."

Shortly after Arnoult's success, a second species, Polypterus ornatipinnis, was spawned by Armbrust for the first time (1966 and 1973) and bred subsequently by Azuma in 1986; Wolf, 1992; Bartsch and Britz, 1996.

[8] In 2014 researchers at McGill University (published in the journal Nature) turned to Polypterus to help show what might have happened when fish first attempted to walk out of the water.

The team of researchers raised juvenile Polypterus on land for nearly a year, with the aim of revealing how these 'terrestrialized' fish looked and moved differently.

When the muscles are relaxed, the bony scales spring back into position, generating negative pressure within the torso, resulting in a rapid intake of air through the spiracle.

1907), The Work of John Samuel Budgett, Balfour Student of the University of Cambridge: Being a Collection of His Zoological Papers, together with a Biographical Sketch by A .

The complete mitochondrial DNA sequence of the bichir (Polypterus ornatipinnis), a basal ray-finned fish: Ancient establishment of the consensus vertebrate gene order.