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A small spider tortoise with yellow web-like lines on its shell.
Photo: Klaus Rudloff, CC BY-SA 4.0, via Wikimedia Commons

Spider Tortoise

Pyxis arachnoides

A tiny, critically endangered Madagascar tortoise named for the web-like yellow lines on its dark shell.

🐢 Turtles and Tortoises
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About the Spider Tortoise

Spider tortoises are the smallest of Madagascar's four native tortoises; the shell grows up to about 7 inches. They live only in a narrow belt of dry, spiny forest along Madagascar's southwestern coast. They eat grasses, young leaves, roots, insects and even cow dung with insect larvae in it. In the dry season they may bury themselves in sand and rest.[1]

Quick facts

Scientific name
Pyxis arachnoides[1]
Size
Shell up to about 7 inches; most are about 4.5 to 5 inches.[1]
Lifespan
Believed to live up to 70 years.[1]
Diet
Grasses, young leaves, roots, insects and cow dung with insect larvae.[1]
Habitat
Dry, sandy spiny forest.[1]
Where it lives
A narrow coastal belt of southwestern Madagascar.[1]
Babies
One egg per clutch; hatches after 220 to 250 days.[1]
Conservation status
Critically Endangered (IUCN Red List, assessed 2008).[2]

Fun facts

  • The yellow lines on its shell look like a spider web.[1]
  • A spider tortoise lays only one egg at a time.[1]
  • It is the smallest tortoise in Madagascar.[1]

Vocabulary

aestivate
To rest in a sleep-like state during hot, dry weather.
carapace
The top part of a turtle's or tortoise's shell.
endemic
Found naturally in only one place in the world.
charcoal
Fuel made by slowly burning wood.
critically endangered
A conservation label meaning a species faces an extremely high risk of dying out in the wild.

See it in person

Sources

  1. [1] Smithsonian's National Zoo & Conservation Biology Institute. “Spider tortoise.” https://nationalzoo.si.edu/animals/spider-tortoise (accessed 2026-10-02)
  2. [2] IUCN Red List of Threatened Species. “Pyxis arachnoides (Spider Tortoise).” https://www.iucnredlist.org/species/19035/177075588 (accessed 2026-10-02)

Facts last checked 2026-10-02.

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