<P> The red - eared slider belongs to the order Testudines, which contains about 250 turtle species . It is a subspecies of Trachemys scripta . They were previously classified under the name Chrysemys scripta elegans . </P> <P> The species Trachemys scripta contains three subspecies: T. s . elegans (red - eared slider), T. s . scripta (yellow - bellied slider), and T. s . troostii (Cumberland slider). </P> <P> The carapace of this species can reach more than 40 cm (16 in) in length, but the average length ranges from 15 to 20 cm (6 to 8 in). The females of the species are usually larger than the males . They typically live between 20 and 30 years, although some individuals have lived for more than 40 years . Their life expectancy is shorter when they are kept in captivity . The quality of their living environment has a strong influence on their lifespans and well being . </P> <P> These turtles are poikilotherms, meaning they are unable to regulate their body temperatures independently; they are completely dependent on the temperature of their environment . For this reason, they need to sunbathe frequently to warm themselves and maintain their body temperatures . </P>

What is the lifespan of a red eared slider turtle
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