Not a tortoise, but a mammal – the Glyptodon

The last new acquisition in our LOST ZOO is a pair of the South American Glyptodon. Most visitors consider the new animals to be giant tortoises. But in fact they are mammals and closely related with the armadillos.Because of its rounded, bony shell and squat limbs the Glyptodon really resembles superficially a turtle. It is covered by a protective shell composed of more than 1,000 about 2.5 cm-thick bony plates,

the so called osteoderms or scutes. These are specific in shape and pattern for each different Glyptodon species. With this protection, the Glyptodons are armoured like turtles. But unlike most turtles, they cannot withdraw their head. Instead they have a bony cap on the top of their skull. Even their tail has a ring of bones for protection. They may have used their tails in competition for resources and also as an ornament when competing for sexual partners. Although its tail could be used for defense against predators, the tail is primarily used for attacks on its own kind.Such a massive shell needs considerable support.

Skeletal specimen of Glyptodon(Click to view larger image).

Therefore the Glyptodon’s fused vertebrae, short but massive limbs, and broad shoulder girdle are not surprising, but the basic requirement for such a heavy shell.Their head has a very special morphology too. The nasal passage is reduced with heavy muscle attachments and the lower jaws are deep and a support for massive chewing muscles to chew coarse fibrous plants.

Vintage drawing of Glyptodon(Click to view larger image).

Their teeth resemble those of an armadillo, but are fluted on each side by deep grooves. A distinctive bar of bone projects downwards on the cheek, extending over the lower jaw, providing an anchor for powerful snout muscles. Our Glyptodon measure 3.3 metres in length, 1.5 metres in height and weigh about 1.400 kg. As the largest representative of their family (Glyptodontidae) they have almost the same size as a modern Black rhino. During the Pleistocene epoch they lived in the South American savannah. At the time when North and South America were connected by the rising of the volcanic Isthmus of Panama, Glyptodon migrated also into Central America as far as Guatemala and about 2.5 million years ago a closely related genus reached even the southern region of the modern USA. Probably as a result from a combination of climatic change and anthropogenic causes,

Back skin of Glyptodon(Click to view larger image).

the Glyptodon became extinct about 12.000 years ago.Because of their body shape and the fusion of the cervical vertebrae, the Glyptodon have to forage near the ground. Their cranio-mandibular joint limited their jaw to side-to-side movement. Based on their anatomical morphology the Glyptodon is a grazer and accustomed to the open grasslands.

Vintage drawing of Glyptodon image(Click to view larger image).

Their diet consists primarily of grass and ground plants which they feed mainly also in our LOST ZOO. In nature they graze especially near water sources such as rivers and lakes, but in our LOST ZOO they prefer special feeding places. Therefore we can attract them to feed near to the visitor’s barrier so that the visitor can observe the animals close.

Executive Curator
JURGEN LANGE