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Re: Ceratosauria vs. Neotheropoda?



 [...] Rowe and Gauthier (1990) defined Ceratosauria as a node-based
 taxon this way: "We employ the name Ceratosauria for the group
 including Ceratosaurus nasicornis, Dilophosaurus wetherilli,
 Liliensternus liliensterni, Coelophysis bauri, Syntarsus
 rhodesiensis, Syntarsus kayentakatae, Segisaurus halli, Sarcosaurus
 woodi , and all other taxa stemming from their most recent common
 ancestor".

(But not that MRCA itself? Bad wording.)

More seriously, this definition looks suspiciously like one of those from the early 1990s that were intended to be branch-based, but some stupid editor or someone told the authors that branch-based definitions are somehow less stable than node-based ones (a fairly widespread belief in those times) and insisted on a node-based one, resulting in a node-based definition with a very, very long list of internal specifiers. We should ignore it for this reason alone (and, as has been pointed out, we can do so because the PhyloCode wasn't implemented yet); we should only consider the intent, which was expressed just fine by the branch-based definitions by Holtz & Padian (1995) and Sereno (2005).