In the South and South East biogeographical zones and Subarid bioclimatic zone (Figs 105-107; Tables 1-3; Appendix II).
In the North West, West and South biogeographical zones and Dry and Subarid bioclimatic zones (Figs 105-107; Tables 1-3).
The major biomes exhibit sharp borders, even in the lowlands, and display a remarkable east-west trend in precipitation, from tropical humid to subarid bioclimatic extremes (Fig.
Humidity transported by the eastern trade winds precipitates on the eastern slopes of the eastern mountain chains, which creates a marked rainfall gradient from the tropical humid north-east and east to the subarid south-west of the island (Vences et al.
From these data it is apparent that the greater number of species occur in the Subhumid zone (eight; five of which occur in remnant fragments of the zone), followed by the Dry (eight), the Humid (six; one fragmented), and the Subarid (five).
But the most abundant lizard of the arid and subarid
regions of western North America is the side-blotched lizard or ground uta (Uta stansburiana), a small iguanid marked with a black patch behind its rear limbs.