244 species worldwide, 19 species in Maryland
As every school kid knows, turtles are the reptiles that carry their house around on their backs. In
softshelled turtles, the shell is made of cartilage. In hardshelled
turtles, it is a bony extension from the ribs. We use the shape of the
carapace (top shell) and the plastron (bottom shell) as one characteristic
to distinguish species. The carapace can be flattened or domed, keeled or
unkeeled, flared or rounded. The scales, or scutes, may smooth or inscribed
and rough. The margins may be notched, serrated, or entire (smooth). The
plastron may have one hinge, or two, which allows the turtle to close up.
Or it may have no hinges. Of course, colors on the shell as well as on the
head, neck and legs are important. We can sometimes use the color of the
eyes to distinguish males from females.
There are six families and nineteen species of turtles (including sea turtles) that can be found in Maryland.
The largest family of turtles worldwide (they are found on every continent except Australia and Antartica), this family is represented in Maryland by eleven species of turtle. With such diversity comes a variety of body types and habitat choices. Usually, the carapace is no highly domed, but there are a few species with high arches to their shells. Many species have a plastron that hinges, allowing for complete or partial closure. Several are almost completely aquatic while others are primarily terrestrial. The name Emydidae comes from the Greek "emys", meaning "freshwater terrapin" some of our turtles will also use brackish water.
Eleven of the nineteen species of turtles in Maryland are from this family. These include: bog turtle (Glyptemys muhlenbergii), spotted turtle (Clemmys guttata), wood turtle (Glyptemys insculpta), eastern box turtle (Terrapene carolina carolina), red-eared slider (Trachemys scripta elegans), midland painted turtle (Chrysemys picta marginata), eastern painted turtle (Chrysemys picta picta), eastern river cooter (Pseudemys concinna concinna), northern red-bellied turtle (Pseudemys rubriventris), northern map turtle (Graptemys geographica), and the northern diamond-backed terrapin (Malaclemys terrapin terrapin).
Photo of Bog Turtle courtesy of Lori Erb
Photo of Spotted Turtle courtesy of Tony Prochaska.
Photo of Wood Turtle courtesy of Linh Phu.
Photo of Eastern Box Turtle courtesy of Scott A. Smith
Terrapine c. carolina
Photo of Red-eared Slider courtesy of John White
Trachemys scripta elegans
Photo of Eastern Painted Turtle courtesy of Corey Wickliffe
Eastern Painted Turtle
Chrysemys p. picta
Midland Painted Turtle Photo Courtesy of Linh Phu
Midland Painted Turtle
Chrysemys picta marginata
Photo of Eastern River Cooter courtesy of John White.
Eastern River Cooter
Pseudemys c. concinna
Photo of Northern Red-bellied Cooter courtesy of John White.
Northern Red-bellied Cooter
Photo of Northern Map Turtle courtesy of Jim Harding
Northern Map Turtle
Photo of Northern Diamond-backed Terrapin courtesy of Lori Erb
Northern Diamond-backed Terrapin
Malaclemys t. terrapin
As the name implies, some of these turtles will release a strong scent when
disturbed. They have paired glands on either side of the body, just inside where
the bridge connects the carapace and plastron. Although they may bask, our two
Kinosternids are primarily aquatic. A good way to tell the difference between
mud and musk turtles is by looking at the plastron. In eastern mud turtles (Kinosternon
subrubrum subrubrum), the plastron is relatively large with
2 hinges. Our eastern musk turtle (Sternotherus odoratus), formerly
called the stinkpot, has a much reduced plastron with only
Photo of Eastern Musk Turtle courtesy of John White
Eastern Musk Turtle
Photo of Eastern Mud Turtle courtesy of Mark Tegges
Eastern Mud Turtle
Kinosternon s. subrubrum
Currently, in the world there are only two living members, or genera, of the Chelydridae family, our own eastern snapping turtle (Chelydra serpentina serpentine) and the alligator snapping turtle, which is not found in Maryland. There are also seven extinct genera of this family.
As the name suggests, this turtle is known for its surly disposition when threatened. Their very long necks allow them to reach farther than other turtles to snap at predators coming from behind. Never pick up a turtle by its tail; this can damage the animal's spine.
Eastern Snapping Turtle
Chelydra s. serpentina
The bony scutes found in hardshell turtles are missing in these softshelled
cousins. The carapace is leathery while the plastron is much reduced. Our one
species, the eastern spiny softshell is primarily aquatic. Their long tubular
snouts act like snorkels, allowing the animals to remain submerged.
Photo of Eastern Spiny Softshell courtesy of Linh Phu
Eastern Spiny Softshell
Apalone s. spinifera
These animals are fully aquatic, emerging from the waters only to breed and
lay eggs. In addition to huge lungs, they can also do without oxygen from the
air as they submerge for up to 30 minutes. Most have hard shells; the
leatherback (our only member of the Dermochelyidae Family) lacks a bony carapace
and instead has skin embedded with little bony deposits over it back.
Maryland species include: Loggerhead Sea Turtle (Caretta caretta), Kemp’s
Ridley Sea Turtle (Lepidochelys kempii), Green Sea Turtle (Chelonia mydas),
Leatherback Sea Turtle (Dermochelys coriacea), and Atlantic Hawksbill Sea Turtle
(Eretmochelys imbricata imbricate).
All species of sea turtles are listed as Threatened or Endangered.
Photo of Loggerhead Seaturtle courtesy of JohnWhite
Photo of Kemp's Ridley Seaturtle Nesting,
courtesy of National Park Service
Kemp’s Ridley Seaturtle
Photo of Leatherback Seaturtle courtesy of Scott R. Benson,
NMFS Southwest Fisheries Science Center
Atlantic Hawksbill Seaturtle
Eretmochelys i. imbricata
580 Taylor Ave, Annapolis MD 21401