Different analyses placed it as either a basal saurischian or an early type of theropod. I decided to compromise between them and make it the basalmost theropod. There really doesn't appear to be much material known from it, so it is pretty hard to place.Ah good. Among the odder parts, I would ask why is- Guaibasaurus basal to Eoraptor and herrerasaurids?
Segisaurus more basal than other coelophysoids?I mainly followed Rauhut's 2000 thesis for the coelophysoids, which placed Segisaurus as the most basal.
"Syntarsus" closer to birds than Coelophysis?It might have had something to do with the life restoration I saw that made it look like a Coelophysis with a Dilophosaurus-like head, but Rauhut found it to be between Segisaurus and Coelophysis. Alternatively, it could be more closely related to Coelophysis than anything else.
Rugops outside the Noasauridae+Abelisauridae clade?My fault for not checking it thoroughly enough. Most of the popular sources like National Geographic make it out to be a basal abelisaur, but upon recently looking up an image of the skull, I find it more likely to be a carnotaurine or at least an abelisaurid. (note to self: don't trust the popular media when it comes to dinosaurs)
Interesting. It seems that coelophysids are pretty distinct when compared to Herrerasaurus, but Eoraptor shares a few characteristics with them that are lost in Herrerasaurus. Could Herrerasaurus have lost them through convergence or could it possibly be more closely related to Dilophosaurus? (I doubt the latter is true)Tykoski (2005) found Liliensternus and Zupaysaurus to share the following characters with other coelophysids- alveolar ridge on maxilla; deep ventral fossa on ectopterygoid; low post-axial cervical neural spines; ischiopubic ratio <66%; proximal end of metatarsal III with ventral boss; anterior ramus of maxilla <10% maxillary length; more than 19 maxillary teeth; anterior margin of antorbital fossa squared; anterior lacrimal process longer than ventral process; cervical ribs fused to vertebrae in adults.Some of those could be primitive characters that were later lost. Are any of these known for Eoraptor or the herrerasaurids?
That's the right question to ask. Eoraptor has the alveolar ridge, Herrerasaurus doesn't. Both have short anterior maxillary rami. Both lack the large maxillary tooth number. Eoraptor has the squared aofo, Herrerasaurus doesn't. Both lack the elongate anterior lacrimal process. The ectopterygoid condition is unknown in both. Eoraptor has low cervical neural spines, Herrerasaurus doesn't. Herrerasaurus lacks fused cervical ribs, Eoraptor's condition is unknown. Both lack shortened ischia. Both lack the metatarsal boss.
What characters join Liliensternus with Dilophosaurus and other theropods?The skeletal reconstructions I found made Liliensternus look like a slightly smaller and more gracile version of Dilophosaurus, with the skull larger relative to the body than in Coelophysis and deeper as well, but not as much as in Dilophosaurus. Though Rauhut did have a monophyletic Coelophysidae, it did show a gradual progression from smaller, more gracile forms like Coelophysis into larger, more robust ones like Liliensternus, and I thought Dilophosaurus would work well as a "next logical step" if things kept going the same direction. However, superficial appearances may well be deceiving, and perhaps I should have examined everything in more depth. Plus, like I said, most of this is a lot of educated guessing as I don't have a cladistics program helping me out.