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The Eastern box turtle (''Terrapene carolina carolina'') is a subspecies within a group of hinge-shelled turtles, normally called box turtles. ''T. c. carolina'' is native to an eastern part of the United States. The eastern box turtle is a subspecies of one of two species of box turtles found in the United States. It is the only "land turtle" found in North Carolina, where it is the state reptile. Box turtles are slow crawlers, extremely long lived, slow to mature, and have relatively few offspring per year. These characteristics, along with a propensity to get hit by cars and agricultural machinery, make all box turtle species particularly susceptible to anthropogenic, or human-induced, mortality. In 2011, citing "a widespread persistent and ongoing gradual decline of ''Terrapene carolina'' that probably exceeds 32% over three generations", the IUCN downgraded its conservation status from Near Threatened to Vulnerable.〔 == Description == Eastern box turtles have a high, dome-like carapace and a hinged plastron that allows total shell closure. The carapace can be of variable coloration, but is normally found brownish or black and is accompanied by a yellowish or orangish radiating pattern of lines, spots or blotches. Skin coloration, like that of the shell, is variable, but is usually brown or black with some yellow, orange, red, or white spots or streaks. This coloration closely mimics that of the winter leaf of the tulip poplar. In some isolated populations, males may have blue patches on their cheeks, throat, and front legs. Furthermore, males normally possess red eyes (irises) whereas females usually display brown eyes. Eastern box turtles feature a sharp, horned beak, stout limbs, and their feet are webbed only at the base. Eastern box turtles have 5 toes on each front leg, and normally 4 toes on each hind leg, although some individuals may possess 3 toes on each hind leg. Staying small in size, most range from 4.5 to 6 inches, but occasionally reach over 7 inches. In the wild, box turtles are known to live over 100 years, but in captivity, often live much shorter lives. Eastern box turtles have many uniquely identifying characteristics which separate them from North American tortoises and water turtles. While the female's plastron is flat, in males it is concave so the male may fit over the back end of the female's carapace during mating. The front and back of the plastron are connected by a flexible hinge. When in danger, the turtle is able to close the plastron by pulling the hinged sections closely against the carapace, effectively sealing the soft body in bone. The shell is made of bone covered by living vascularized tissue and covered with a layer of keratin. This shell is connected to the body through its fused rib cage which makes the shell permanently attached and not removable. When injured or damaged, the shell has the capacity to regenerate and reform. Granular tissue slowly forms and keratin slowly grows underneath the damaged area to replace damaged and missing scutes. Over time, the damaged area falls off, revealing the new keratin formed beneath it. Unlike water turtles such as the native eastern painted turtle (''Chrysemys picta''), box turtle scutes continue to grow throughout the turtle's life and develop growth rings. Water turtles typically shed their scutes as they grow. File:Eastern Box Turtle 8679.jpg|Eastern box turtles laying eggs File:EasternBoxTurtleMale.jpg|Adult male, eastern box turtle File:Terrapene carolina carolina young.jpg|Young box turtle File:Eastern box turtle.JPG|Tomlinson Run State Park, WV File:Terrapene carolina carolina3.jpg|Shenandoah National Park, Virginia File:Eastern Box Turtle Pond.JPG File:Terrapene fg02.jpg|Plastron fully closed File:EasternBoxTurtle2010.jpg|''T. c. carolina'' at the Louisville Zoo 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Eastern box turtle」の詳細全文を読む スポンサード リンク
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