Tetrapod ancestors updated back to Cambrian finless fish

Pictures tell the story, for the most part today.
The large reptile tree
(LRT, 1615+ taxa) presents an occasionally novel and growing list of taxa between Cambrian pre-fish and the first listed tetrapod, Laidleria (Fig. 1 bottom). This list is updated from the previous time this list was first presented without so many basal chordates. Note, it still does not include traditional members, Acanthostega and Ichthyostega. which nest at more derived nodes as they venture back into a more fish-like niche.

Figure 1. These taxa are those closest to main line of tetrapod ancestors. That makes these taxa human ancestors, too.

Figure 1. These taxa are those closest to main line of tetrapod ancestors. That makes these taxa human ancestors, too.

Qiao et al. 2016 report,
“Our findings consistently corroborate the paraphyly of placoderms, all ‘acanthodians’ as a paraphyletic stem group of chondrichthyans, Entelognathus as a stem gnathostome, and the Guiyu-lineage as stem sarcopterygians.”

Figure 3. Traditional cladogram from Lingham-Soliar 2014.

Figure 2. Traditional cladogram from Lingham-Soliar 2014. This has been invalidated by the LRT.

Figure 4. Subset of the LRT with the addition of several jawless taxa.

Figure 3. Subset of the LRT with the addition of several jawless taxa.

References
Brazeau MD and Friedman M 2015. The origin and early phylogenetic history of jawed vertebrates. Nature. 2015;520(7548):490–7. pmid:25903631.
Davis SP, Finarelli JA and Coates MI 2012. Acanthodes and shark-like conditions in the last common ancestor of modern gnathostomes. Nature. 2012;486(7402):247–250. pmid:22699617
Dupret V, Sanchez S, Goujet D, Tafforeau P and Ahlberg PE 2014. A primitive placoderm sheds light on the origin of the jawed vertebrate face. Nature. 2014;507:500–503. pmid:24522530
Lingham-Soliar T 2014. The vertebrate integument volume 1. origin and evolution. Springer.com  PDF
Qiao T, King B, Long JA, Ahlberg PE and Zhu M 2016. Early gnathostome phylogeny revisited: multiple method consensus. PLoS ONE 11(9): e0163157. https://doi.org/10.1371/journal.pone.0163157
Zhu M, Zhao W-J, Jia L-T, Lu J, Qiao T and Qu Q-M. 2009. The oldest articulated osteichthyan reveals mosaic gnathostome characters. Nature. 2009;458:469–474. pmid:19325627
Zhu M, Yu X-B, Ahlberg PE, Choo B, Lu J, Qiao T, et al. 2013. A Silurian placoderm with osteichthyan-like marginal jaw bones. Nature. 2013;502(7470):188–193. pmid:24067611
Zhu M, Yu X-B and Janvier P 1999. A primitive fossil fish sheds light on the origin of bony fishes. Nature. 1999;397:607–610.

https://pterosaurheresies.wordpress.com/2019/10/24/tetrapod-evolution-without-ichthyostega-and-acanthostega/

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