Phylogenetic Systematics oflguanine Lizards 



contained Lacerta iguana (=Iguana iguana), the single known iguanine, and animals now 

 placed in at least 12 different families, including crocodilians and amphibians. He 

 considered them to be "foul and loathsome animals" (Linnaeus, 1758, translated in Goin et 

 al., 1978). At the close of the eighteenth century only three of the currently recognized 

 iguanine species (now placed in two genera) had been described, giving the systematists of 

 that century, such as Laurenti (1768) and Lacepede (1788), Uttle of a group to recognize. 



The Nineteenth Century. Major advances in iguanine systematics came during the 

 nineteenth century. Many important natural histories and systems or classifications of 

 squamates appeared during these years, and by 1856 all of the currently recognized 

 iguanine genera had been described. 



The concept of a natural iguanine taxon emerged during the first half of the nineteenth 

 century. Most of the authors of classifications published during this period recognized a 

 close relationship among at least some of the iguanine genera. Those that did not recognize 

 a complete and exclusive group for the iguanines known at the time failed to do so for one 

 or both of two reasons. Brongniart (1805), Latreille (1825), Fitzinger (1826, 1843), 

 Wagler (1830), and Dumeril and Bibron (1837) grouped all the known iguanines together, 

 but included some noniguanines with them. Although all the iguanines were sometimes 

 placed together as part of a continuous list, it is not evident that they were considered to 

 form their own subgroup within some larger group. Other authors such as Daudin (1805), 

 Merrem (1820), Cuvier (1829, 1831), and Wagler (1830) failed to place all iguanines in a 

 single group. Daudin, Cuvier, and Wagler included Brachylophus with the agamids, while 

 Merrem did the same for Ctenosaura. 



At least three authors can truly be said to have recognized an iguanine group before 

 1850. I have two criteria for determining the true recognition of an iguanine group. First, 

 all of the iguanine taxa known to the author (or at least all those listed in the classification) 

 were included in the group; and second, no other taxa were included. Cuvier's (1817) 

 "Les Iguanes proprement dits" consisted of what are now Iguana iguana, I. delicatissima, 

 Cyclura cornuta, and Brachylophus fasciatus, although he later removed Brachylophus and 

 placed it among the agamids (Cuvier, 1829, 1831). Wiegmann (1834) placed only the 

 genera Cyclura, Ctenosaura, Iguana, Brachylophus, and Amblyrhynchus in his family 

 Dendrobatae, Tribus II, b, ***, B. Like many of his contemporaries, Wiegmann 

 constructed his classification as a hierarchy of sets and subsets that would also function as 

 a key. 



The most fully developed early concept of an iguanine group appears to have been that 

 of Gray (1831a, 1845). In 1831, Gray placed all known iguanines (equivalent to what are 

 now 10 species in five genera) by themselves in a single genus, Iguana. Fourteen years 

 later, he recognized nine different iguanine genera. Because these nine genera (again 

 equivalent to five modem genera) formed one entire set in his hierarchical classification, it 

 is evident that Gray still recognized the unity of the iguanine group. 



Progress in iguanine systematics, though less rapid than in the previous fifty years, 

 continued through the second half of the nineteenth century. The last two iguanine genera 

 that are still recognized, Dipsosaurus and Sauromalus, were described, but at first they 



