Traditional bony evolved from spiny sharks in the LRT

Recent housekeeping
in the large reptile tree (LRT, 2189 taxa, Fig 2) now nests all the extant and extinct pachycormiformes (Figs 3, 4), with the Devonian spiny sharks (Fig 1, Acanthodii).

This is yet another example of why we should not list traits to determine clades. Rather we should use the last common ancestor method to determine clades (using traits, not genes). That means we writers and readers are also members of the monophyletic Acanthodii.

Spiny sharks (Acanthodii)
are not strange long lost oddities. They are ancestors of all bony fish and descendants of placoderms. Two early splinters (Fig 2, Osteoglossum and Notopterus, Fig 5) survive to this day.

As transitional taxa,
spiny sharks demonstrate transitional morphologies between placoderms and bony fish. The genesis of this transition is once again marked by phylogenetic miniaturization with Shenacanthus, about the size of an inch worm.

According to Wikipedia,
“Pachycormiformes are generally interpreted as members of Teleosteomorpha, the group that includes all fish more closely related to modern teleosts than to Holostei (the group containing bowfin and gars), often they have been considered to be the sister group of the Aspidorhynchiformes.”

In the LRT Aspidorhynchus (Fig 3) is instead a clade member of the Pachycormiformes.

Contra Wikipedia, in the LRT, members of the traditional Holostei do not nest together, so that’s an invalid clade. BTW, in the LRT no taxa are ever ‘considered’. All taxa are tested.

Earlier
the extant bronze featherback, Notopterus (Fig 5), nested with spiny sharks like Brochoadmones. Now these two are joined by pachycormiformes in the LRT (subset Fig 2). Osteoglossum, the extant arowana, also arises (splits off earlier on.

A popular little spiny fish, the stickleback
(Gasteroseus), is not related to Devonian spiny sharks (Acanthodii), despite their many spiny fins. Spiny pelvic and dorsal spines reappear here perhaps due to a genetic reversal becayse acanthodiians are in the lineage of sticklebacks and tetrapods, like the stegosaur, Kentrosaurus.

References
wiki/Pachycormiformes
wiki/Acanthodii
wiki/Aspidorhynchiformes