Archelon — Microsoft Dinosaurs

Archelon

AR-keh-lon name means “Sea-living turtle”

This sea turtle was as big as a car!

KindPrehistoric creature Period Late Cretaceous Diet Carnivore

Imagine a turtle thirteen feet long! The giant Cretaceous turtle, Archelon, lived at the same time as the dinosaurs. Turtles are one of the oldest surviving groups of reptiles and have changed little through the centuries. Archelon had giant paddle-like flippers to propel its enormous body through the water.

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A Variety of Turtles

When most people think of turtles, they imagine a hard-shelled animal like this one. But turtles come in all shapes and sizes. There are between 250 and 350 species of turtles around today.

Hard-shelled terrapinPond terrapins, like this one, are mainly vegetarians and spend most of their time in the water.

Soft-shelled turtleNot all turtles have hard shells. This soft-shelled turtle is usually found buried in mud in rivers and ponds.

LeatherbackExperts think Archelon most resembled this leatherback turtle. This giant is the largest of all living turtles, and can weigh over 2,000 pounds. Like Archelon, a leatherback's diet consists mostly of jellyfish.

Reptiles of the Sea

There were no dinosaurs that lived at sea, yet when dinosaurs ruled the land, the seas were filled with swimming reptiles of all shapes and sizes. Alongside turtles such as Archelon swam marine reptiles that were divided into four main groups: ichthyosaurs, pliosaurs, plesiosaurs, and mosasaurs.

PlesiosaursThese reptiles had four paddle-like limbs, pointed tails, long necks, and small heads.

PliosaursThese reptiles were similar to plesiosaurs, but had larger heads and shorter necks.

IchthyosaursThese reptiles had streamlined shapes, fin-like arms, and a fish-like tail.

MosasaursThese fierce sea reptiles had sharp fang-like teeth and a tail like a crocodile. They lived toward the end of the Age of Dinosaurs.

Jellyfish Chewer

Archelon had a hard, hooked beak, weak jaws and no teeth. It may have used its bony beak to crunch through shellfish, but soft jellyfish were probably its favorite food.

Ancient swimmersSoft-bodied marine creatures are some of the oldest animals that we know about. Jellyfish have been around since the Precambrian era, more than 600 million years ago!

Egg Layers

Modern sea turtles lay eggs on land, even though they live at sea. Different species of turtles lay their eggs in different habitats: some lay eggs in sand, some in leaf litter, and still others lay their eggs in the burrows of other animals.

By the dozenThe number of eggs a turtle may lay is largely dependent on its size. Giant sea turtles may lay as many as 100 eggs. Experts aren't sure how many eggs Archelon may have laid.

Egg shapesThese turtle eggs are rounder than many of their dinosaur counterparts.

Egg shellsTurtle eggs contain liquid and have leathery shells for protection. As with crocodiles, the sex of baby turtles is often determined by the temperature of incubation. Before birth, a turtle embryo develops into an animal able to breathe air and live on land.

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Life Before Dinosaurs Living Fossils Mosasaurus Ammonite Nests and Eggs

Source: Microsoft Dinosaurs (1993) CD-ROM. Text liberated from original screen art; images & audio restored from disc. Original media is Microsoft/supplier copyright — non-commercial educational preservation. Credits & Acknowledgements