Oldest Sea Turtles in the World

10 Oldest Sea Turtles in the World

In general, very few sea turtles are in captivity around the world. Sea turtles typically only end up in aquariums and conservatories when they have suffered serious injuries or an illness left them handicapped. Due to this and the fact that sea turtles are hard to track, there aren’t any notable individuals who have reached an old age (there are a few rumors of various aquariums having very old individuals, but these are unconfirmed rumors). Instead, this list covers the oldest species of turtles, both living and dead.

Sea turtles have been around for over 100 million years and most of the species have gone extinct. Today, there are only seven existing species of sea turtles left in the world. Unfortunately, all of the remaining sea turtles are endangered, which is why there are stringent conservation laws in place around the world to protect them. The ages for the modern species of turtles is based on this chart discussing the evolution of sea turtles.

10. Ridley Sea Turtles – Olive Ridley (Lepidochelys olivacea) and Kemp’s Ridley (Lepidochelys kempii)

Age of Species: about 30 million years for both
Average Lifespan:  about 50 years for both
Location:  Olive Ridley – tropical and subtropical waters of the Pacific, Indian, and Atlantic Oceans; Kemp’s Ridley – primarily in the Gulf of Mexico
Diet:  Omnivorous – crustaceans, mollusks, clams, mussels, shrimp, and fish

Kemp's Ridleyphoto source: Kemp’s Ridley – Wikimedia Commons via U.S. National Park Service

Olive Ridleyphoto source: Olive Ridley – Wikimedia Commons

Kemp’s ridley are two closely related turtles and the last remaining species in the genus Lepidochelys. The two ridley turtles share many of the same characteristics, including their unique mass nesting event called an arribada. Thousands of females of either species will gather together at a nesting beach where they will simultaneously lay their eggs.

Olive ridleys are the most abundant of all turtle species, while Kemp’s ridleys are the most endangered. Kemp’s ridleys are also the smallest in size. Not much is known about either species as olive ridley and Kemp’s ridleys are largely solitary – they usually only gather during mating and nesting season. Both species of ridley turtles are endangered, with Kemp’s ridleys being highly vulnerable. However, conservation efforts in recent years have helped the Kemp’s ridley partially recover its numbers.

9. Loggerhead (Caretta caretta)

Age of Species: about 35 million years
Average Lifespan:  47 – 67 years
Location:  Every ocean around the world; mostly in the temperate tropical and subtropical regions of the Atlantic, Pacific, and Indian Oceans
Diet:  Primarily carnivorous – crustaceans, fish, whelks, other mollusks, horseshoe crabs, sea urchins, and other invertebrates

Loggerheadphoto source:  Wikimedia Commons

The loggerhead sea turtle was named for its relatively large head, which has heavy and very strong jaws. Although loggerheads are omnivorous, they prefer to prey on smaller marine animals and use their hard jaws to eat hard-shelled prey like crustaceans and whelks. Loggerheads are the largest hard-shelled sea turtle, second in size to the leatherback, and can weigh up to 250 pounds.

A unique trait of loggerheads is that they often appear to be “crying.” This is nothing to be worried about and is just a special adaptation – loggerheads have salt glands near their eyes that allow them to drink salt water and the “tears” are just the excess salt. Loggerheads are also known for their long migrations, with some groups migrating over entire oceans between foraging areas and nesting beaches.

8. Hawksbill (Eretmochelys imbricata)

Age of Species: about 35 million years
Average Lifespan:  30 – 50 years
Location:  Tropical and subtropical waters of the Atlantic, Pacific, and Indian Oceans
Diet:  Sponges, anemones, squid, sea grasses, sea urchins, and shrimp

Hawksbillphoto source:  Flickr via U.S. Fish and Wildlife Service Southeast Region

The hawksbill sea turtle is known for its beautifully patterned shell, which was referred to as “tortoiseshell.” Prior to the ban on the tortoiseshell trade, hawksbill shells were widely used for ornamental purposes, including jewelry, combs and brushes, hair decorations, and furniture. The beauty of the hawksbill’s shell was nearly its downfall and they were almost hunted to extinction. While real tortoiseshell is illegal today, a thriving black market still exists and synthetic tortoiseshell is a popular material.

Some of the sponges, anemones, and other small coral reef creatures that hawksbills eat are toxic. Due to this, hawksbill meat is poisonous to humans. Unfortunately, this has not discouraged people from hunting the hawksbill for its meat. The number of remaining hawksbills is so low that the species is in danger of extinction within the foreseeable future.

7. Flatback (Natator depressus)

Age of Species: about 40 million years
Average Lifespan:  80 or more years
Location:  Waters around Australia and Papua New Guinea
Diet:  Sea cucumbers, jellyfish, mollusks, prawns, other invertebrates, and seaweed

Flatback (Natator depressus)photo source:  Wikimedia Commons

The flatback sea turtle was named for its uniquely flat shell, which differs from the curved shells of other sea turtles. Flatbacks have the smallest distribution of all sea turtles and are only found in the waters near Australia and Papua New Guinea – they only breed and nest in Australia. Due to their remote habitat, flatbacks have not been as thoroughly studied as the other species of sea turtle.

Flatbacks lay the largest eggs of any sea turtle, but only lay about half as many eggs as the other species. Aside from threats from humans, flatbacks are preyed on by saltwater crocodiles, dingos, foxes, sand monitor lizards, feral pigs, pelicans, and night herons.

6. Green Sea Turtle (Chelonia mydas)

Age of Species: about 45 million years
Average Lifespan:  80 or more years
Location:  Tropical and subtropical waters around the world
Diet:  Adults are herbivorous – sea grasses and algae; juveniles are omnivorous – invertebrates like crabs, jellyfish, and sponges

Green Turtlephoto source:  Wikimedia Commons

When people think of sea turtles, chances are they’re picturing the iconic green turtle, who is easily identified by its hard top shell. Unlike other sea turtles, the green turtle has only a single pair of scales in front of its eyes, instead of the two pairs of other hard shell sea turtles. Despite the misconception, green turtles were not named for the color of their shells, which are not always green, but for the color of their greenish skin.

Green turtles are typically divided into two subspecies, the green turtle (Chelonia mydas mydas) and the black or Eastern Pacific green turtle (Chelonia mydas agassizii). There is an ongoing debate over whether or not the two subspecies are actually two separate species. Another unique feature of the green turtle is that its diet changes drastically as it ages. Juvenile green turtles are omnivorous and will eat worms, crustaceans, jellyfish, grasses, and algae; when they become adults, green turtles are strictly herbivorous.

5. Archelon ischyros

Age of Species: between 66 million – 80 million years
Average Lifespan:  Unknown – possibly up to 100 years old
Location:  Fossils found in South Dakota and Wyoming, USA
Diet:  Soft-bodied animals, such as jellyfish and cephalopods

Archelon ischyrosphoto source:  Wikimedia Commons

Archelon ischyros, commonly called just Archelon, is probably the most famous ancient sea turtle outside of scientific circles. Archelon has become famous for being the largest turtle that has ever been discovered – the largest fossil measures more than 13 feet (4 m) in length and is 16 feet (about 5 m) wide. The first and one of the most complete Archelon specimens was discovered in 1895 by Dr. George R. Wieland.

The leatherback is Archelon’s closest living relative and the two sea turtles share several characteristics.  Like the leatherback, Archelon had a flexible and thin shell that was spread over a ribbed frame. Archelon also had large and very wide flippers, which helped propel it through water. While its difficult to determine how long Archelon turtles typically lived, one specimen from the Vienna Museum of Natural History is estimated to have died when it was about 100 years old.

4. Leatherback Sea Turtle (Dermochelys coriacea)

Age of Species: Unknown for sure – lineage arose between 90 – 100 million years ago
Average Lifespan:  45 years
Location:  World wide open ocean, as far north as Alaska and as far south as the southern tip of Africa
Diet:  Soft-bodied animals, especially jellyfish; seaweed; fish; crustaceans; and other marine invertebrates

Leatherback Sea Turtlephoto source:  Flickr via U.S. Fish and Wildlife Service Headquarters

Of the seven remaining species of sea turtles, the leatherback is the most unique and is the only surviving member of the Family Dermochelyidae. The leatherback’s lineage goes back about 100 million years.

Leatherbacks have several unique features different from all other modern sea turtles, the most notable is its soft, flexible, rubbery, leather back. Additionally, leatherbacks are the largest sea turtle and the largest living reptile found anywhere in the world. They are also specialized divers and are capable of diving as deep as 4,000 feet. Like all sea turtles, leatherbacks were once more abundant, but are now listed as an endangered/vulnerable species.

3. Ctenochelys acris

Age of Species: about 80 million years
Average Lifespan:  Unknown
Location:  Fossils discovered in Alabama, USA; lived in shallow subtropical sea that used to cover the area that is now Alabama
Diet:  Mollusks and small invertebrates

Ctenochelys acrisphoto source:  ScienceDaily

In late 2016, new research from the University of Alabama at Birmingham revealed that the relatively unknown Ctenochelys acris is the oldest known member of the lineage that gave rise to the modern sea turtle. According to the research team, Ctenochelys acris lived more than 80 million years ago at a time when the diversity of sea turtle species was high. Before the new research was released, there was little fossil evidence of C. acris and many paleontologists doubted the sea turtle’s existence.

The University of Alabama researchers compared the fossils of C. acris with fossils from both living and extinct species of turtles. They discovered that C. acris had traits of sea turtles and their closest relatives, snapping turtles. The study also revealed that C. acris “was a bottom-dwelling sea turtle that fed primarily on mollusks and small invertebrates” and had “large, powerful hind-limbs to help push it through the water, a lot like a modern-day snapping turtle.”

2. Santanachelys gaffneyi

Age of Species: about 110 million years
Average Lifespan:  Unknown
Location:  Fossils discovered at the Santana Formation, Brazil
Diet:  Unknown

Santanachelys gaffneyiphoto source:  Wikimedia Commons

Until a few years ago, Santanachelys gaffneyi was cited as the oldest known sea turtle – it was dethroned by another extinct sea turtle that is over 10 million years older. Although S. gaffneyi is no longer the oldest, it is still an ancient sea turtle that lived during the Early Cretaceous period (over 110 million years ago).

While Santanachelys gaffneyi has many of the same characteristics as modern sea turtles, it also differs in several ways. Instead of the digitless flippers that modern sea turtles have, S. gaffneyi had a couple of movable digits on its forearms. It is believed that this was a common feature of early sea turtles who had not yet evolved the paddle-like flippers of modern sea turtles. However, S. gaffneyi did have large salt glands near its eyes, which were suited for a marine environment.

1. Desmatochelys padillai

Age of Species: over 120 million years old
Average Lifespan:  Unknown
Location:  Fossils discovered in Villa de Leyva, Colombia
Diet:  Unknown

Desmatochelys padillaiphoto source:  Live Science

Although the most complete fossil of Desmatochelys padillai was discovered in 2007, the true age of this sea turtle ancestor was not described until 2015. That year a paper was published following new research into the fossil, which revealed that Desmatochelys padilli is over 120 million years old, making it the oldest sea turtle in the world. While many extinct species of marine turtles are not related to modern sea turtles, scientists confirmed that D. padilli is the oldest, definitive, marine turtle known to date.

Desmatochelys padillai was a massive turtle, with a length of nearly 6.5 feet (2 m). This ancient sea turtle also exhibits all of the characteristics of modern sea turtles.



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