Grand Canyon Black Tarantula

a black tarantula spider with 8 legs and a brown abdomen blends in against a background of rocks, twigs and pine needles.
Grand Canyon tarantulas are most visible in the fall, when males search for mates.

Photo courtesy of Chris Hamilton

Scientific Name

Aphonopelma marxi


  • Tarantulas grow to a large size- Grand Canyon black tarantulas grow up to 4 inches (10cm) from leg tip to leg tip. The goliath bird-eating spider (Theraphosa blondi) is the world's largest species of tarantula. Found in South America, it can reach up to 11 inches (28cm) from leg tip to leg tip.
  • Tarantula burrows are silk-lined holes in the ground. Tarantulas use silk as a frame to prevent the burrow from collapsing.
  • All tarantulas are covered in thick hair. Grand Canyon black tarantulas are dark in color, and the hair on the abdomen is reddish or orange in color.


  • Tarantulas live are found throughout the Grand Canyon. Tarantulas inside the Canyon tend to grow slightly larger than tarantulas on the Rim.
  • They spend most of their lives in underground burrows.


  • During most of the year, both males and females spend most of the time in their burrow, only moving short distances at night to hunt.
  • Most sightings are during the autumn months, when males leave their burrows and wander constantly looking for a mate.
  • Tarantulas will not bite unless they feel very threatened, and the pain of a tarantula bite is comparable to a wasp sting. The main defense for North and South American tarantulas are urticating, or barbed, hairs. When threatened, a tarantula will brush these barbed hairs from their body into the air, where they lodge in the eyes, nose, and mouth of attackers, causing extreme irritation.
  • Tarantulas prey on everything from insects to small rodents. After a large meal, a tarantula may not feed again for months.
  • Tarantulas are the prey of some birds, lizards, and giant centipedes. The most famous creature that preys on tarantulas is the tarantula hawk.

More Information

  • Tarantulas are not dangerous, but their bite is painful. While these spiders are large, they can be easily harmed if dropped or stepped on. Please observe these incredible arachnids from a distance.
Prepared by Matthew M. Safford, Wildlife Technician, Grand Canyon National Park, November 2015.

Grand Canyon National Park

Last updated: November 21, 2022