Reproductive ecology of the whiptail lizard Cnemidophorus lineatissimus (Squamata : Teiidae) in a tropical dry forest

We studied the reproductive ecology of the teiid lizard Cnemidophorus linea tissimus during 1993 and 1994 near Chamela, Jalisco, Mexico. We estimate th at males reached sexual maturity at a snout-vent length (SVL) of 51 mm and an age of five months, and females reached sexual maturity at a SVL of 62 m m and an age of seven months. Testicular mass increased from April to July, reaching maximal size between August and December, and decreased in Januar y of the next year. Gonads of females began to increase in mass during June when vitellogenesis occurred. They reached maximum mass from July to Novem ber when most egg production occurred. Some egg production occurred in Janu ary as well. The reproductive season for males and females is extended, sim ilar to many other tropical lizards. Mean crutch size was 4.1 +/- 0.2 eggs. Clutch size was correlated with female size, but egg size and relative clu tch mass remained constant among females and between pars. Mean clutch size and female body condition were lower in 1993 compared to 1994, presumably reflecting the effects of annual variation in resource availability on fema les. Proximal climatic factors influence the timing and intensity of reprod uction in C. lineatissimus, but the historical effect of foraging mode on t eiid lizard morphology constrains relative clutch mass. Sexual dimorphism i s evident with males reaching larger size than females, and seasonal variat ion in mean SVL in both sexes suggests that much of the population is repla ced annually.