Sea Turtle Identification

These marine reptiles are characterized by a large, streamlined shell (carapace), and non-retractable head and flippers.  In all species except the leatherback, the body is covered with hard, keritinized plates called "scutes".  The number and arrangement of scutes on the carapace and head are used to identify between the species.

Sea turtles range in color from pale green to almost black.  Jaw shape also varies among species, adapted to its diet.  There is no sexual dimorphism (physical differences between males and females) with the only difference in adult turtles being the size of the tail.  Adult males have a much wider and longer tail than females.

Leatherback

Scientific name:  Dermochelys coriacea

• The largest sea turtlle
• 4-8 feet in length (1.2-2.4 meters)
• Smooth, leathery, flexible carapace (shell)
• No scutes (scales)
• Black in color with white, pink, and greyish spots
• Longitudinal ridges running the length of the carapace
• 500-2000 pounds (225-900 kg)

Visit our leatherback page for more information.

Green

Scientific name:  Chelonia mydas

• Largest of the hard-shelled sea turtles
• Up to 4 feet (1.2 meters) in length
• Carapace color ranges from olive brown to almost black
• 4 pairs of costal scutes
• A single pair of scales between the eyes (prefrontal scutes)
• Scutes do not overlap
• "Sunburst" pattern on scutes
• Up to 500 pounds (225 kg)

Visit our green turtles page for more information. 

Loggerhead

Scientific name:  Caretta caretta

• up to 4 feet (1.2 meters) in length
• named for it's massive head/jaws
• carapace (shell) is reddish-brown in color
• 5 pairs of costal scutes
• 2 pairs of prefrontal scutes
• carapace in slightly heart-shaped
• skin and plastron (belly) yellow in color
• scutes (scales) do not overlap
• 200-400 pounds (90-180 kg)

Visit our loggerhead page for more information.

Hawksbill

Scientific name:  Eretmochelys imbricata

• 2-3 feet (.5-1 meter) in length
• One of the smaller species
• Overlapping scutes (scales) on carapace (unique to this species)
• 4 pairs of costal scutes
• 2 pairs of prefrontal scutes
• Named for its narrow head and bird-like beak
• Brightly colored carapace (shell)
• 100-200 pounds (45-90 kg)

 Visit our hawksbill page for more information.

Olive Ridley

Scientific name:  Lepidochelys olivacea

• Named for its pale green carapace (shell)
• 2 to 2.5 feet (~.6 meters) in length
• Slightly heart-shaped carapace
• 6 or more pairs of costal scutes
• 2 pairs of prefrontal scutes
• 75-100 pounds (34-45 kg)
• The most abundant species

Visit our olive ridley page for more information.

Kemp's Ridley

Scientific name:  Lepidochelys kempii

• The smallest species
• Up to 2 feet (.6 meters) in length
• Triangular shaped head and hooked beak
• 5 pairs of costal scutes
• 2 pairs of prefrontal scutes
• Olive-grey carapace (shell)
• Almost circular carapace is as wide, or wider as it is long
• The only species of sea turtle that nests primarily during the day
• 75-100 pounds (34-45 kg)

 Visit our Kemp's ridley page for more information.

Flatback

Scientific name: Natator depressus

• Named for its flat carapace (shell)
• Up to 3 feet (.9 meters) in length
• Pale greyish-green carapace
• 4 pairs of costal scutes
• Single pair of prefrontal scutes
• Edges of carapace are distinctly upturned
• Up to 200 pounds (90 kg)
• Only found in waters around Northern Australia and Southern Indonesia

Visit our flatback page for more information.

Links & Resources

Seaturtle.org: Sea Turtle Identification Key

WIDECAST-Sea Turtle Terminology for Identification

Sea Turtle Conservancy-Online Sea Turtle Species Identification Key

Euro Turtle- Sea Turtle Identification Diagram

Nature Photo Essay: Sea Turtle Anatomy

What Is SEE Turtles?

We're a non-profit that promotes conservation travel through wildlife tours that help protect sea turtles and other endangered species. We work with quality tour operators who have passed our criteria to ensure low environmental impact. We're part of The Ocean Foundation.