Actinopteri Explained

Actinopteri is the sister group of Cladistia (bichirs) in the class Actinopterygii (ray-finned fish).

Dating back to the Permian period, the Actinopteri comprise the Chondrostei (sturgeons and paddlefish), the Holostei (bowfins and gars), and the teleosts; in other words, all extant ray-finned fish other than the bichirs.

In this clade the lungs have evolved into a swim bladder.^[1]

Characters of Actinopteri include ^[2] paired fin structure, a single dorsal fin, fulcra, a large median gular and numerous branchiostegals, ganoid scales, and a valvula cerebelli in the brain.

Classification

The following cladogram^{[3] [4] [5]} summarizes the evolutionary relationships of extant Actinopteri. Divergence time for each clade in mya are based on:^[6]

Notes and References

1. Funk . Emily . Lencer . Ezra . McCune . Amy . September 2020 . Dorsoventral inversion of the air-filled organ (lungs, gas bladder) in vertebrates: RNA-sequencing of laser capture microdissected embryonic tissue . Journal of Experimental Zoology. Part B, Molecular and Developmental Evolution . 334 . 6 . 325–338 . 10.1002/jez.b.22998 . 8094346 . 32864827. 2020JEZB..334..325F .
2. Patterson . Colin . 1982. Morphology and Interrelationships of Primitive Actinopterygian Fishes . American Zoologist . 22 . 241 . 241–259 . 10.1093/icb/22.2.241 .
3. Web site: Betancur-R . Phylogenetic Classification of Bony Fishes Version 4 . 2016 . 2017-03-29 . 2017-07-11 . https://web.archive.org/web/20170711171156/https://sites.google.com/site/guilleorti/classification-v-4 . dead .
4. Book: Nelson, Joseph, S.. Fishes of the World. 2016. John Wiley & Sons, Inc. 9781118342336 .
5. Web site: R. Froese and D. Pauly. FishBase . February 2006.
6. Resolution of ray-finned fish phylogeny and timing of diversification . Thomas J. Near . PNAS . 10.1073/pnas.1206625109 . 2012 . 109 . 34 . 13698–13703. etal . 22869754 . 3427055. free . 2012PNAS..10913698N .