Actinopterygian

2004, M. L. J. Stiassny, E. O, Wiley, G. D. Johnson, M. R, de Carvalho, 24: Gnathostome Fishes, Joel Cracraft, Michael J. Donoghue (editors), Assembling the Tree of Life, page 416, The most basal of living actinopterygians are the bichirs (Polypteridae), a small group (11 spp.) of African fishes previously thought to be related to the lobefin fishes (sarcopterygians), or to form a third group.

[…] actinopterygians have 'ray fins' which are supported by a series of narrow cartilaginous or bony rods called radials, while sarcopterygians have 'lobe fins' supported by a single basal bone and with muscles that can modify the posture of the fin.

The ear of all nonteleostean actinopterygian fishes (Grande and Bemis 1996) does not differ much from that of ratfish (considered by most an ancient line of cartilaginous fish), with the notable exception of the position of the ultricular macula.

The otico-orbitotemporal region is formed by a single ossification in primitive actinopterygians but by many separate ossifications in advanced actinopterygians, expecially teleosts.

Already some years ago it was pointed out that the skeleton of the pelvic fin and girdle of Polypterus is much more actinopterygian than crossopterygian in structure.

Still more Actinopterygian is the skeleton of the pelvic fin; here only four bony radials are preserved, separately articulating with the pelvic girdle.