Updated June 27, 2022
with a renesting of many placoderms close to galeapsids near the base of the Vertebrata. These developed jaws by convergence with gnathostomes. Ptyctodontida continue to nest with catfish in the LRT (2119 taxa in 2022).
The LRT divides placoderms into three clades;
- Arthrodira (open ocean predators like Dunkleosteus, Coccosteus, Fig. 3)
- Antiarchi (armored jawless bottom dwellers like Dicksonosteus, Bothriolepis, Fig. 2)
- Phyllolepida (tiny-eye taxa like Entelognathus, Cowralepis)
Several traditional placoderms nest elsewhere in the LRT.
- Rhenanida – nests with manta rays in the LRT
- Wuttagoonaspis – nests with catfish in the LRT
- Stensioellida – nests with Guiyu-like lobefins in the LRT
- Brindabellspida – nests with the tetrapodomorph Elpistostege in the LRT
- Ptyctodontida (chimaera-like taxa like Australoptyctodus, nest with catfish in the LRT)
Several traditional placoderms have not yet been tested in the LRT.
- Petalichthyida (includes Diandongpetalichthys)
- Acanththoraci (closely related to rhenanids, nesting with manta rays)
- Pseudopetalichthyida (similar to rhenanids, nesting with manta rys)
Ptyctodonts, like Austroptyctodus,
(Fig. 2) do not nest with other traditional placoderms in the LRT, but nest closer to Cheirodus. These are the sort of results the LRT recovers only because it tests more taxa.
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