Tortoise, Angulated

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Tortoise, angulated

Geochelone yniphora

phylum: Chordata

class: Reptilia

order: Testudines

family: Testudinidae

status: Endangered, IUCN Endangered, ESA

range: Madagascar

Description and biology

The angulated tortoise, also known as the Madagascar tortoise or angonoka, is a large animal. Its rotund carapace (pronounced KAR-a-pace), or top shell, measures 18 inches (46 centimeters) long. Dark wedge-shaped markings appear across this light brown carapace. The tortoise's characteristic feature is a hornlike protuberance, or projection, that juts out under-neath its neck from its plastron, or ventral (bottom) shell. A herbivore (plant-eater), the tortoise feeds mainly on leaves, grasses, and shoots.

Biologists (people who study living organisms) have very little information on the angulated tortoise's breeding habits in the wild. Those tortoises in captivity have been observed mating between October and February. Males engage in duels, apparently over the right to mate with females.

Habitat and current distribution

Unique to Madagascar (an island off the southeast coast of Africa), the angulated tortoise is found in a limited area around Baly Bay, in the northwestern part of the island. The tortoise prefers to inhabit a mixture of tropical deciduous (shedding trees and plants) forests and grasslands.

Since only a few hundred angulated tortoises remain in the wild, the animal is seriously threatened with extinction.

History and conservation measures

Between the seventeenth and twentieth centuries, angulated tortoises were hunted in great numbers for food. Malagasy law now protects the tortoise from such hunting, but serious threats remain. Predators, such as wild pigs, destroy the tortoises' nests. Much of the tortoises' habitat has been cleared and converted into farmland.

In 1986, the Jersey Wildlife Preservation Trust and the Department of Waters and Forests of Madagascar mounted a species recovery plan for the tortoise. The plan includes breeding the tortoise in captivity, preserving its natural habitat, and educating local people about the threat facing the tortoise.

In May 1996, 73 young tortoises and 2 adult females were stolen from the captive-breeding compound in northwestern Madagascar. Officials believed the angulated tortoises were taken to be sold illegally to collectors.