ABSTRACT 



Sukhanov, V. B. SOME PROBLEMS OF THE PHYLOGENY AND SYSTEMATICS OF LACERTILIA 

 (SEU SAURIA). Zoologicheskiy Zhurnal, vol. ko , no. 1, p. 73-83, 1961. The 

 study of lizard musculature differentiates two strikingly different 

 locomotor mechanisms; Scincogekkonomorphous sind Iguanomorphous , both of 

 which have tended to evolve in different directions. The locomotion of the 

 Gekkota can also be divided into two types: Scincomorphous - crawling - 

 and Iguanomorphous - where the body is held high above the substrate. The 

 locomotion of gekkotan lizards, although having a more archaic appearance, 

 shares some basic features with the locomotion of scincomorphans. Differ- 

 ing from the generally accepted lizard classification of Charles L. Camp 

 (1923), the Gekkota and Scincomorpha are here suggested to be different 

 branches of the same evolutionary lineage (division Scincogekkonomorpha) . 

 A second lineage of lizard evolution (division Iguanomorpha) possesses a 

 greatly modified locomotor apparatus, perhaps due to their aboreality. 

 The common ancestors of Scincogekkonomorpha and Iguanomorpha are postu- 

 lated to have had a peculiar type of locomotion not found in its entirety 

 in extant lizards: their bodies were raised high above the substrate, (as 

 in Gekkota and Iguajiomorpha) , proximal parts of limbs moved nearly in a 

 horizontal plane (as in Gekkota and Scincomorpha). The similarity of the 

 Gekkota and Iguanomorpha results mainly from parallel or convergent evolu- 

 tion and not by close relationship. 



TEXT 



The present article discusses one of the most controversial issues con- 

 cerning the phylogeny of lizards - the relationships between the Iguano- 

 morpha (families Iguanidae eind Agamidae), the Scincomorpha and the Gekkota. 



We find one of the first attempts to classify lizards on a phylogenetic 

 basis in several of E. D. Cope's works (I86U, 1900). At the base of his 

 tree he placed the iguanids and agamids (Pachyglossa) , assuming that gekko- 

 tano (Nictisaura) descended from them by degeneration. Cope felt that the 

 relationship of the scincids and lacertids with Pachyglossa was more remote 

 - through the Diploglossa (Anguidae, Varanidae, etc.). 



^Studied: Gekkonidae - Gekko gecko, Teratoscincus scincus , Cyrtodacty- 

 lus caspius; Scincidae - Eumeces schneideri, Mabuya sp.; Lacertidae - 

 Lacerta lepida, L. agilis; Eremias grammica, E. arguta, E. velox; Agamidae - 

 Agama agilis sanguinolenta, A. caucasica, Phrynocephalus mystaceus , P. 

 inters capxilari s , P. reticulatus, P. helioscopus. 



References to earlier works dealing with the system of reptiles can be 

 found in Camp (1923). 



