Maryland's Turtles & Tortoises (Order Testudines)

19 native species and 3 introduced/naturalized

Turtles are the reptiles that carry their house around on their backs. In softshelled turtles, the shell is made of cartilage. In hard-shelled 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 be 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.

Turtle and Tortoise Anatomy​

Turtle FamilyNumber of Species & Subspecies in Maryland
Box and Water Turtles (Emydidae)12
Musk and Mud Turtles (Kinosternidae)3
Snapping Turtles (Chelydridae)1
Softshell Turtles (Trionychidae)1
Sea Turtles5

Box and Water Turtles (Emydidae)

The largest family of turtles worldwide, the Emydidae family, is represented in Maryland by thirteen species of turtle. With such diversity comes a variety of body types and habitat choices. Usually, the carapace is not 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", but some of our turtles will also use brackish water.​​

Photo of Bog Turtle courtesy of Stephen Badger
Bog Turtle​ (G​lyptemys muhlenbergii​)​
Photo courtesy of Stephen Badger

Photo of Spotted Turtle courtesy of Tony Prochaska.

​Spotted Turtle​​ (Clemmys guttata​)
Photo courtesy of Tony Prochaska
Photo of Wood Turtle courtesy of Linh Phu

Wood Turtle (Glyptemys insculpta)
Photo courtesy of Linh Phu
Photo of  Eastern Box Turtle courtesy of Scott A. Smith

Eastern Box Turtle (Terrapene​ carolina​​)
Photo courtesy of Scott A. Smith
Photo of Red-eared Slider courtesy of John White

Red-eared Slider (Trachemys scripta elegans)
Photo courtesy of John White
Photo of Eastern Painted Turtle courtesy of Corey Wickliffe

Eastern Painted Turtle (Chrysemys p. picta​)
Photo courtesy of Corey Wickliffe​
Midland Painted Turtle Photo Courtesy of Linh Phu

Midland Painted Turtle (Chrysemys picta marginata)
Photo courtesy of Linh Phu​​
Photo of River Cooter courtesy of John White.

​River Cooter (Pseudemys concinna​​)
Introduced; not established in Maryland yet
Photo courtesy of John White
Former Name: Eastern River Cooter
Photo of Northern Red-bellied Cooter courtesy of John White.

Northern Red-bellied Cooter (Pseudemys rubriventris​)
Photo courtesy of John White
Photo of Northern Map Turtle courtesy of Jim Harding

Northern Map Turtle (Graptemys geographica​​​)
Photo courtesy of Jim Harding
Diamond-backed Terrapin (Malaclemys terrapin​​)
Photo courtesy of Lori Erb
Former Name: Northern Diamond-backed Terrapin
​​​False Map Turtle by Peter Paplanus CC by 2.0
False Map Turtle (Graptemys pseudogeographica​)
Photo courtesy of by Peter Paplanus CC by 2.0
Yellow-bellied Slider by Alexandru Panoiu CC by 2.0
Yellow-bellied Slider (Trachemys scripta scripta)
Photo courtesy of John White

Musk and Mud Turtles (Kinosternidae)

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), 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 1 hinge.​

Photo of Eastern Mud Turtle courtesy of Brenda and Jim Bardsley
(Kinosternon baurii)
Photo courtesy of Brenda and Jim Bardsley
Photo of Eastern Mud Turtle courtesy of Mark Tegges
(Kinosternon subrubrum)
Photo courtesy of Mark Tegges
Photo of Eastern Musk Turtle courtesy of John White

​​Eastern Musk Turtle (Sternotherus odoratus)
Photo courtesy of John White

Snapping Turtles (Chelydridae)

Currently, in the world there are only two living members, or genera, of the Chelydridae family, our own snapping turtle (Chelydra serpentina) 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.​

Photo of Snapping Turtle courtesy of Linh Phu

Snapping Turtle (Chelydra serpentina​)
Photo courtesy of Linh Phu​​
Former Name: Eastern Snapping Turtle

Softshell Turtles (Trionychidae)

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 but still breathe.​

Photo of Spiny Softshell courtesy of Linh Phu​
Spiny Softshell (Apalone spinifera​​)
In Need of Conservation
Photo courtesy of Linh Phu​​
Former Name: Eastern Spiny Softshell

Sea Turtles (Cheloniidae and Dermochelyidae)

These turtles 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.

All species of sea turtles are listed as Threatened or Endangered.​​​​​​​​​

Loggerhead seaturtle, photo by John White
Loggerhead Sea Turtle (Caretta caretta)
Photo courtesy of John White
​​Kemp Ridley Sea Turtle by NPS
Kemp’s Ridley Sea Turtle (Lepidochelys kempii​​)
Photo courtesy of the National Park Service
​​Photo courtesy of iStock
Green Sea Turtle (Chelonia mydas​​)
Photo courtesy of iStock
Photo of Leatherback Seaturtle courtesy of Scott R. Benson, NMFS Southwest Fisheries Science Center
Leatherback Sea Turtle (Dermochelys coriacea​​)
Photo courtesy of Scott R. Benson, NMFS Southwest Fisheries Science Center
​​​Hawksbill Sea Turtle, photo by iStock
Hawksbill ​Sea Turtle​ (Eretmochelys imbricata​)​
Former Name: Atlantic Hawksbill Sea Turtle
Photo courtesy of iStock​
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