Theropods in the LRT with suggested nomenclature

Figure 1. Lately the two clades based on two specimens of Compsognathus (one much larger than the other) have merged recently.

Figure 1. Lately the two clades based on two specimens of Compsognathus (one much larger than the other) have merged recently. Names posted here are in use traditionally, but with different definitions in some cases.

Just a moment to update
the theropod subset of the large reptile tree (LRT, 1151 taxa). Given the present taxon list, this is the order they fall into using the generalized characters used throughout the LRT. Validation is required for all such first-time proposals. The names applied here are used in traditional studies, but often not following previous definitions or clade memberships.

The large and small Compsognathus specimens
are closely related, but not congeneric (Fig. 2).

Figure 1. The large (from Peyer 2006) and small Compsognathus specimens to scale. Several different traits nest these next to one another, but at the bases of two sister clades. Note the differences in the forelimb and skull reconstructions here. There may be an external mandibular fenestra. Hard to tell with the medial view and shifting bones.

Figure 2. The large (from Peyer 2006) and small Compsognathus specimens to scale. Several different traits nest these next to one another, but at the bases of two sister clades. Note the differences in the forelimb and skull reconstructions here. There may be an external mandibular fenestra. Hard to tell with the medial view and shifting bones.

Does anyone see
in this list two ‘related’ taxa that do not resemble one another more so than any other taxon? If so, that needs to be noted and repaired.

2 thoughts on “Theropods in the LRT with suggested nomenclature

  1. Ah, I’m not. In that case, Coelophysidae’s definition is Megapno+Coelo, so would exclude Dracoraptor. The whole group is Coelophysoidea, with all the theropods closer to birds than it Averostra.

    Your ‘Ceratosauridae’ would make most sense being Carnosauria (all closer to Allo than to birds), while your ‘Compsognathidae’ is closest in concept to Holtz’s (1994) Arctometatarsalia (all closer to Ornithomimus than to birds). Within your Carnosauria, I’d suggest Spinosauroidea vs. Megalosauroidea. Within that Arctometatarsalia, you’d have Ornithomimosauria plus Tyrannosauroidea, and a Caengnathiformes including Therizinosauria and Oviraptorosauria. Note your Arctometatarsalia plus taxa closer to birds is Coelurosauria.

    Your ‘Dromaeosauridae’ is actually Maniraptora (all closer to birds than Ornithomimus). Your ‘Velociraptorinae’ is Deinonychosauria (all closer to Deinonychus than birds), in your case inclding Dromaeosauridae and Alvarezsauroidea. You can’t place Velociraptorinae without knowing where Dromaeosaurus goes.

    Your ‘Troodontidae’ is Avialae. Your Enantiornithes is fine, and that plus all closer to birds is Ornithothoraces. Scansoriopterygidae is node-based, so would exclude Mei, Jeholornis, Archaeovolans and the Arch specimens. The Zhong+Confuc+grandis clade is Confuciusornithiformes. You’d need Changchengornis to know where Confuciusornithidae goes, your ‘Confuciusornithidae’ is Pygostylia. And your “Euornithes’ is Aves.

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