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University of California Publications in Zoology 



B 



FIG. 16. Posterodorsal views of disarticulated right palatines of (A) Iguana delicatissima (MCZ 75388) 

 and (B) Conolophus subcristatus (AMNH 110168), contrasting the low dorsomedial ridge in the former 

 with the high dorsomedial crest in the latter. Abbreviations: c, dorsomedial crest; mp, maxillary process; 

 ptp, pterygoid process; r, dorsomedial ridge; vp, vomerine process. 



iguanines, and five categories can be recognized (Fig. 17): (1) entirely within the palatine 

 without a suture connecting the foramen to the lateral edge of the palatine (Fig. 17 A); (2) 

 within the palatine with a suture running from the foramen to the lateral edge of the palatine 

 (Fig. 17B) (individuals falling within this category vary considerably in the distance from 

 the foramen to the lateral edge of the palatine and thus the length of the suture); (3) between 

 the palatine and the jugal (Fig. 17C) (sometimes the lacrimal also contributes to the border 

 of the foramen); (4) between palatine and maxilla with the portion of the palatine directly 

 posterior to the foramen large but not extending laterally to contact the jugal (Fig. 17D); (5) 

 between palatine and maxilla, with the portion of the palatine directly posterior to the 

 foramen small or absent (Fig. 17E). 



Intrageneric and intraspecific variation in the position of the iguanine infraorbital 

 foramen is great: many genera and species exhibit more than one of the five conditions 

 described above. Nevertheless, sufficient differences exist among genera that some of the 

 variation can be used in phylogenetic analysis. Most iguanines (Amblyrhynchus, 

 Conolophus, Ctenosaura, Cyclura, Iguana, and Sauromalus) commonly exhibit condition 

 3, in which the infraorbital foramen is located at the suture between palatine and jugal. 

 Conolophus, Cyclura, and Iguana are relatively constant in the position of this foramen: 

 the great majority of individuals in these three genera exhibit condition 3. Amblyrhynchus, 

 Ctenosaura, and Sauromalus are more variable. Though condition 3 occurs commonly in 

 all three genera, in Amblyrhynchus and Ctenosaura the infraorbital foramen of many 

 individuals is entirely within the palatine. A suture connecting the foramen to the lateral 



