Accordingly, while females have relatively short fingernails, males have extraordinarily long fingernails to better facilitate this behavior. Additionally, the vent or cloacal opening will be located closer to the base of the tail in females, closer to the tip of the tail in males. Tails Though interpreting the gender of a turtle by examining its tail is not as easy for beginners as some other methods, it is the most consistent indicator across a variety of species. Fingernails The easiest way to tell the gender of a red-eared slider Trachemys scripta or painted turtle Chrysemys picta is to look at the animal's fingernails. With most of a turtle's anatomy hidden betwixt its shell, discerning one's gender is accomplished by examining a combination of size, tail, fingernails and plastron shape. There are some exceptions, though, particularly among species that are semi-aquatic, like the Blanding's turtle Emydoidea blandingii , or those that walk along the bottom of the water, like the stinkpot turtle. Shell Shape Males of terrestrial species, like box turtles Terrapene carolina and tortoises Geochelone sp. With practice, these clues can be observed at a distance, allowing the identification of even a wild turtle's sex. Females of many aquatic species, like red-eared sliders and soft-shell turtles Apalone sp. Most male turtles will have longer, thicker tails than females will to contain the male's phallus. Unfortunately, this isn't always a helpful criteria; northern populations of stinkpot turtle Sternotherus odoratus feature larger males than females, while southern populations show the opposite trend.