The seven classified species of marine turtles cruising the world's oceans all developed from a single, unique group that separated from other turtle species over 100 million years ago. This group then split into two families, Cheloniidae and Dermochelyidae, that represent all sea turtles in the world today.
Six of the seven species of marine turtles are classified within the hard-shelled Cheloniidae:
1. Caretta caretta (Loggerhead)
2. Chelonia mydas (Green turtle)
3. Eretmochelys imbricata (Hawksbill)
4. Lepidochelys kempii (Kemp's Ridley)
5. Lepidochelys olivacea (Olive Ridley)
6. Natator depressus (Flatback)
The family Dermochelyidae is represented solely by the unique Dermochelys coriacea (Leatherback), lacking the hard shell that characterizes other marine turtles.
Many scientists also consider the distinctive 'black' turtles of the Pacific coast of the Western Hemisphere, sometimes referred to as Chelonia agassizii, as an eighth species.
Marine turtles can be found in every major ocean throughout the world. While most species are found primarily in tropical and subtropical waters, individuals have been known to venture into the colder waters of the Arctic.
Images on species pages © CÉSAR LANDAZABAL / CONSERVATION INTERNATIONAL |
