Endemism, gigantism and extinction in island lizards: the genus Gallotia on the Canary Islands

In the Canary Islands five extant and two extinct giant lacertid lizards be longing to the endemic genus Gallotia are known. A comparative study of the living and subfossil specimens from the Western Canary Islands demonstrate s that the extinct giant species Gallotia goliath and Gallotia maxima are s ynonymous with the living Gallotia simonyi. Characters formerly used in the diagnosis of the extinct species and subspecies fall within the range of i ntraspecific variation (ontogenetic and individual) of the living species. The only significant difference between living and subfossil populations of G. simonyi is size, and there is strong evidence to suggest that the reduc tion in size in living populations reflects shorter life expectancy, a fact or that should be taken into account in the current conservation projects o n this species.