Goliath birdeater spider
Photo by Photo © <a href="https://www.flickr.com/photos/[email protected]/">John 'snakecollector'</a> / Flickr

Scientist Piotr Naskrecki encountered a puppy-sized spider on a recent nighttime walk in a rainforest in Guyana.

Naskrecki, an entomologist and photographer at Harvard University’s Museum of Comparative Zoology, had come across the South American Goliath birdeater (Theraphosa blondi). The Goliath birdeater is the world’s largest spider, according to Guinness World Records.

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According to Naskrecki, the Goliath birdeater’s leg span can reach up to a foot, or about the size of “a child’s forearm,” with a body the size of “a large fist.” Naskrecki also said that “[its] feet have hardened tips and claws that produce a very distinct, clicking sound, not unlike that of a horse’s hooves hitting the ground.”

When Naskrecki approached the Goliath birdeater, the spider began to rub its hind legs against its abdomen in order to send out a cloud of hairs with microscopic barbs on them as its first line of defense. The hairs are meant to be “extremely painful and itchy” when they get in the eyes or other mucous membranes.

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The Goliath birdeater also has a pair of 2-inch-long fangs as a method of self-defense. Although the spider’s bite is venomous, it’s not deadly to humans. Naskrecki said that it would still be extremely painful to be stung by a Goliath birdeater, “like driving a nail through your hand.”

For more information, visit LiveScience.com.

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