Table 1. Comparison of interpretation of selected morphology from previous and current studies of Pachyrhachis problematicus. Ue1-ue5 refer to the elements illustrated in figure 5 of this study. See Figure 2 for illustrations and interpretations of previous studies.
Haas 1979, 1980a | Caldwell and Lee 1997 | Zaher and Rieppel, 1999b | This Study |
Postfrontals | Jugals | Broken displaced anterior ectopterygoids | Ventral portion of postorbitals (ue1&ue2) |
Not applicable | Postfrontal fused to postorbital | Crushed frontalis decensus | Anterior portion of ectopterygoid (ue3) |
Anterior portion of left ectopterygoid | Posterior left maxilla | Not applicable | Anterior portion of left ectopterygoid |
Posterior portion of left ectopterygoid | Ectopterygoid | Not applicable | Posterior portion of left ectopterygoid |
Right ectopterygoid | Posterior right maxilla | Posterior right maxilla | Posterior right maxilla |
Not applicable | Medial processes of postorbital | Not part of postorbital | Possibly crushing of parietal table (ue4&ue5) |
Stapes | Tentative squamosal | Stapes | Stapes |
Not applicable | Stapes | Paroccipital process of opisthotic | Stapes |
Not applicable | Vertically oriented quadrate | Posterventrally inclined quadrate | Posteroventrally inclined quadrate |
Not applicable | Two mental formina | One mental foramen | One mental foramen |
Not applicable | Broad lateral profile of quadrate | No suprastapedial process of quadrate | No suprastapedial process of quadrate |
Not applicable | Broad lateral profile of quadrate | More Macrostomatan-like quadrate | Stylohyal process on ventral medial margin |
Not applicable | Exoccipitals do not contact | Unknown | Unknown |