Odp: [dinosaur] Diadectomorphs and seymouriamorphs as amniotes from inner ear morphology

Trilos are most likely mandibulates according to recent papers. If truly so, they fit in the crown. However, the name Arthropoda seems to be falling out of favour lately. 
            
          
     
      
       
        Dnia 11 października 2019 21:32 David Marjanovic <[email protected]> napisał(a):
       
    
       
         
 Disagree. The standard usage of "stem-" in invertebrate paleo refers to members outside the crown group but closer to it than to the next closest crown group (so stem-arthropod, stem-mollusk, etc.). But "non-crown amniotes" is (as noted) a nonsensical term. 
 
  
 But "members of a taxon, but not of its crown-group" is exactly what "stem-group" has meant ever since Hennig. I don't think I've seen phylogenetic definitions for Arthropoda or Mollusca, and Arthropoda at least is usually treated as having an apomorphy-based definition (it's not clear if even the trilobites are crown-group arthropods, but they're not going to be kicked out of Arthropoda!), so there are non-crown arthropods = stem-arthropods.