Genus Chrysemys

Gray, 1844
Painted turtles

The only living species in this genus is Chrysemys picta, the painted turtle of North America.

McDowell (1964) revised the New World emydid genus Chrysemys on the basis of skull and foot morphology, including in it C. picta and the cooter and slider turtles of the genera Pseudemys and Trachemys, and suggested that three subgenera were involved (Chrysemys, Pseudemys, and Trachemys). Similarities in the choanal structure of Chrysemys picta and various species of Pseudemys and Trachemys upheld both their placement within the genus Chrysemys and McDowell's subgeneric distinctions (Parsons, 1968). Zug (1966) found little variation in the penial structure of Chrysemys picta and Trachemys scripta, Pseudemys nelsoni, P. peninsularis and P. concinna, strengthening the inclusion of these turtles within Chrysemys. Weaver and Rose (1967) concurred with the inclusion of Pseudemys and Trachemys in Chrysemys, but showed the subgenera to be invalid, based on further examination of skull and shell characters. Ernst and Barbour (1972) and Conant (1975) accepted Chrysemys as the generic name for these turtles. However, there remained much disagreement about the generic arrangement of these turtles, and many experts still maintained that Pseudemys (including Trachemys scripta) was a separate genus.
Holman (1977) expressed doubts about the status of McDowell's (1964) genus Chrysemys. He pointed out that under McDowell's concept as many as four congeneric species may occur in the same water body in the southeastern United States and that, although they have similar courtship patterns, there are no records of hybridization between Chrysemys picta and other species of Chrysemys. However, hybrids are known within the subgenus Pseudemys, and intergrades C. c. floridana x C. c. concinna (Smith, 1961; Mount, 1975), and C. c. concinna x C. rubriventris (Crenshaw, 1965). Holman (1977) urged additional study of the relationships within the genus. Subsequently, the morphological, cytological, biochemical, and parasitological characteristics have been re-evaluated (Ernst and Ernst, 1980; Vogt and McCoy, 1980; Seidel and Smith, 1986). These new studies indicate that Chrysemys, Pseudemys, and Trachemys are best treated as separate genera.