16 



38. — . 1969. Reproduction in Cnemidophorus inornatus and _C. neo - 

 mexicanus . PH.D. DISS., UNIVERSITY OF NEW MEXICO. 2if7 p. 



The only piece of information not contained in the following re- 

 port is the tendency of individuals of both species to seek refuge in a 

 particular burrow even if they have "to run through a gauntlet of coll- 

 ectors" to get there. This implies that lizards are highly sedentary, 

 that individuals are resident in a particular area. There is no indi- 

 cation of intraspecific territoriality in either species, however. 



39. _. 1971. Reproduction of Cnemidophorus inornatus and Cnemido - 

 phorus neomexicanus (Sauria, Teiidae) in northern New Mexico. AMER- 

 ICAN MUSEUM NOVITATES No. 2^*42: 1-48. 



Cnemidophorus inornatus inhabits primarily undisturbed desert 

 grasslands in the Albuquerque region whereas C. neomexicanus is found 

 chiefly in disturbed areas, often man-related, and is able to survive 

 under nearly metropolitan conditions. The two species are reproduc- 

 tively isolated by their habitat preferences, reinforced by the aggres- 

 sive nature of _C. neomexicanus towards _C. inornatus . The two species 

 manifest similar seasonal activities. _C. inornatus males are more ac- 

 tive early in the year and females are more active late in the year. 

 Adults of both species cease surface activity by the third week in Sep- 

 tember and juveniles by the first week of October. Lizards emerge from 

 hibernation in mid-April; juveniles are more active than adults for a 

 few weeks in spring and before hibernation begins in the fall. The 

 male reproductive cycle of jC. inornatus is described. Maximum testi- 

 cular size is achieved in April and maximum sperm production occurs in 

 May through the first week of June. Minimum testicular size occurs in 

 late 3uly-early August and growth occurs throughout the winter. The 

 fat body cycle is approximately the reverse. The female reproductive 

 cycle is nearly identical for both species. Follicular enlargement of 

 up to 3 per lizard begins in April-May, the first ovulations occur in 

 the last week of May through the first week of June, and eggs are laid 

 from the first week of June through the third week of July (peaks in 

 mid-June). Approximately 25% of the females of both species lay a se- 

 cond clutch. The mean clutch size for both species is 2.13, but ovar- 

 ian foUicules and oviducal eggs are considerably larger in jC. neomex- 

 icanus . The first hatchlings appear in the last two weeks of July, and 

 new hatchlings continue to appear until the first week of September. 

 Individuals of both species can live for 4 calendar years; 25% possibly 

 live for 5. Individuals are not reproductively mature until their 3rd 

 calendar year. _C. neomexicanus populations possess double the repro- 

 ductive potential of C. inornatus populations by virtue of parthenogen- 

 esis; it is suggested that the viability of eggs of the former species 

 is only 1/2 that of the latter, although no evidence for this exists in 

 this situation. The displacement of _C. inornatus by _C. neomexicanus is 



