Minor changes to the large reptile tree

Adding a few taxa to the large reptile tree generally causes a reassessment of past scorings that stand out as autapomorphies. Some of these represent earlier mistakes. When the mistakes are corrected the tree can shift the nesting of taxa. Some taxa are only one or two steps away from a minor shift anyway, especially the incomplete taxa. So this can happen. No major tree topologies have changed, however.

Previously nested outside of the Archosauria, Turfanosuchus now nests at the base of the Dinosauriformes along with the PVL 4597 specimen attributed to Gracilisuchus, Trialestes and Herrerasaurus, which drops out of the Theropoda.

Batrachotomus and Saurosuchus
Now nest together. No biggie.

The nesting of the referred specimen of Brazilosaurus at the base of the Thalattosauria somehow shifted Largocephalosaurus and Sinosaurosphargis back to the base of the Sauropterygia (placodonts + plesiosaurs). These two are so different from their sisters, yet this nesting is only held in place by a few steps. And it’s still entirely possible that the dermal armors of saurosphargids and placodonts were derived independently.

The list of protodiapsids have arranged themselves into three distinct clades, shortening the phylogenetic distance between the basal synapsid Archaeothyris and basal diapsids like Tangasaurus (Enaliosauria) and Thadeosaurus (Younginids and Archosauriformes).

The basal reptile Cephalerpeton now nests basal to only the new Lepidosauromorpha. This makes the Reptilia truly diphyletic following the tiny Gephyrostegus specimen. Cephalerpeton shares more traits with those early captorhinomorph herbivores than the more insectivorous and lizardy Brouffia, at the base of the new Archosauromorpha.

Milleretta RC14 and Bolosaurids
Bolosaurids now nest separate from the caseids and the higher Lepidosauromorpha.

Odontochelys, still not a turtle
Odontochelys nests outside of the clade that produced Proganochelys, so developed its turtle-like traits by convergence based on the current list of characters and taxa. Another putative turtle ancestor, Eunotosaurus nests closer to caseids.

Tritosaurs up to 18+ taxa
Not bad for a totally new clade… Not counting all the pterosaurs, drepanosaurs, macrocnemids, etc. the Tritosauria now number 18 in the large reptile tree. Let’s put some more of these former oddballs and former enigmas into lepidosaur trees to confirm or deny this topology.

It just takes a little effort and a sense of wonder. And take off those blinders!

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