Apalone ferox – Florida Softshell Turtle

Species Recognition. — The Florida softshell, Apalone ferox, is the largest of the three softshell turtle species found in Florida and has the darkest coloration. It is also the only softshell species found throughout the length of the peninsula. Adults are large to very large (up to 43.6 kg and 73.6 cm carapace length), flat, brown turtles with a cartilaginous shell that is covered by skin rather than by the hard scutes typical of most other families of turtles (Fig. 8-1). All softshells have strongly webbed feet with three claws on each foot. They also have a long neck, a distinct tubular snout, and fleshy lips that cover their jaws (Figs. 8-2, 8-3). The bones of the plastron are visible through the connective tissue of the shell and are much reduced compared to those of most other turtles (Fig. 84). The Florida softshell can be distinguished from the other two species found in Florida by its larger size and a distinctive patch of well-developed low tubercles on the anterior margin of the carapace that grade laterally into a marginal ring (Fig. 82). In the smooth softshell (Apalone mutica) this area is smooth (Figs. 9-1, 9-2), in the spiny softshell (Apalone spinifera) this area is covered by numerous fine spines with a few tubercles in larger adults (Figs. 10-1, 10-2, 10-3). Hatchlings of the Florida softshell have a light colored carapacial rim that is lost with age. Hatchlings and juveniles have a tan to light brown carapace with chocolate brown mottling and a gray or black plastron (Figs. 8-3, 8-5). With age the mottling intensifies and covers most or all of the carapace, making it all dark brown. The head of juveniles is brown to black and streaked with yellow stripes or blotches that are usually lost in adults. Juveniles and males of the two other softshells found in Florida (A. mutica and A. spinifera) have a beige to gray carapace with distinct dark flecks or rings (Fig. 9-3). In Florida, these two species tend to retain their juvenile coloration throughout life although large adult females of both species lose the juvenile coloration. Furthermore, in these two species, the head is colored as the carapace, and any yellow lines are set off from the background color by black borders, which is usually not the case in adult A. ferox. Taxonomic History. — This species was originally described as Testudo ferox by Schneider (1873) on the basis of material that probably came from the Savannah River, which forms the Georgia–South Carolina border. The type specimen is an entire, stuffed adult in the British Museum of Natural History, BMNH 1947.3.6.17 (Webb, 1973; King and Burke, 1989). This species and A. spinifera were considered to be a single species by certain authors (Neill, 1951; Carr, 1952; Crenshaw and Hopkins, 1955) until the work of Schwartz (1956) and Webb (1962). Thus, some earlier work referring to A. ferox may actually describe A. spinifera (e.g., Breckenridge, 1955). The generic names Trionyx, Platypeltis, and Amyda have previously been used for this species. It is currently referred to the genus Apalone Rafinesque based on the work of Meylan (1987). No subspecies are recognized; however, distinctive genetic variation exists among populations within PETER A. MEYLAN AND PAUL E. MOLER