Spiny softshell turtle
The spiny softshell turtle (Apalone spinifera) is a species of softshell turtle, one of the largest freshwater turtle species in North America. Both the common name, spiny softshell, and the specific name, spinifera (spine-bearing), refer to the spiny, cone-like projections on the leading edge of the carapace, which are not scutes (scales). Description The spiny softshell turtle's scientific name is very descriptive of the animal. Apalone comes from the Greek word apalos, meaning soft or tender, and spinifera is of Latin origin; spina- referring to thorn or spine and -ifer meaning bearing. This species is a member of the family Trionychidae, and one of the most distinguishing features of members in this family is the presence of a leathery, moderately flexible carapace. This is caused by loss of keratinized scutes and some bony tissue loss. Spiny softshell turtles have webbed feet, each with three claws. Another distinguishing feature of softshell turtles is the presence of a fleshy, elongated nose. The carapace (the upper part of the shell) ranges from brown or yellow-brown to olive in color, while the plastron (lower part of the shell) is lighter, usually white or yellow. Hatchlings usually have dark spots on the carapace, but as females age, they frequently become darker in color, or their carapace becomes splotched. Males tend to maintain the same coloration pattern from birth. Coloration also varies between each subspecies, and the exact coloration can also depend on an individual turtle's environment. Spiny softshell turtles are cryptically colored, meaning that their coloration helps them blend in with their surrounding environment. Spiny softshell turtles also have pale lines bordered by black lines running from its head down the side of its neck. The carapace length ranges from , with females growing larger than males. The namesake spines are found along the anterior border of the carapace and are more commonly found in males. The variation in coloration, size, and spine presence indicates that this species exhibits sexual dimorphism. Distribution Geographic range This species is the most widely distributed softshell turtle in North America. The spiny softshell has a wide range, extending throughout much of the United States, as well as north into the Canadian provinces of Ontario and Quebec, and south into the Mexican states of Tamaulipas, Nuevo León, Coahuila and Chihuahua. As of recently, the spiny softshell has expanded its geographic range (through human assistance) into Washington State and California. Ecological range Spiny softshell turtles are often referred to as ecological generalists, meaning that they are found in a wide variety of habitats. The spiny softshell can be found in bodies of fresh water including ponds, lakes, rivers, tributaries, and streams. They can persist in more urban environments as they are well adapted to periodic habitat disturbances. They inhabit shallow water less than deep, but can also be found as far as deep. When swimming, a study suggests that they get most of their thrusting power from their forelimbs as opposed to their hindlimbs, which is common in other species. They